The document discusses Java bytecode, how to compile Java programs, operator precedence in Java expressions, arrays in Java, implementing inheritance in Java, and different types of exceptions in Java. It provides examples and explanations of each topic in 3-6 paragraphs per section.
The document provides an introduction to the Java programming language. It discusses that Java was originally called Oak and developed by Sun Microsystems in 1991. It can be used to create both applications and applets. The source code is compiled into bytecode, which is then interpreted by the Java Virtual Machine (JVM) to execute programs. Key features of Java include being simple, secure, portable, object-oriented, robust, and multi-threaded. The document also covers concepts such as packages, interfaces, inheritance, method overloading/overriding, and multithreading.
The document provides an overview of object-oriented programming (OOP) concepts and the Java programming language. It discusses key OOP concepts like encapsulation, inheritance, polymorphism and abstraction. It then describes how to write, compile and run a basic Java program. Key aspects of the Java language like classes, objects, methods and constructors are explained. The document also discusses how Java programs are executed using a Java Virtual Machine (JVM).
Mahika Tutorials sharing PPT slide for core java programming language. Go threw this slide and visit our YouTube page too
https://www.youtube.com/c/mahikatutorials
This document provides an overview of the Java programming language as presented by Ms. Surbhi Saroha. It covers topics such as Java overview, data types, control structures, arrays, strings, classes, inheritance, packages, exceptions, and more. The document contains slides with explanations, examples, and code snippets to illustrate key concepts of the Java language.
This document provides information about a student named Mohd. Shahnawaz Alam enrolled in the third semester of a B.Sc. (IT) program. It includes their roll number, book information, and questions about features of Java, executing Java programs, operators in Java, character extraction functions, types of relationships in Java, differences between errors and exceptions, and syntax for FileInputStream and FileOutputStream classes. The document contains detailed responses to each question providing explanations of concepts and code examples.
Java defines data as objects with methods that support the objects. It provides features like abstraction, encapsulation, inheritance and polymorphism. Java programs can be executed on any platform that supports a Java Virtual Machine as Java code is compiled to bytecode, which is platform independent. To execute a Java program, the source code must be compiled to bytecode using the javac compiler, which checks for errors. The bytecode can then be executed using the java command.
The document discusses Java interview questions and answers. It covers topics like the differences between JDK, JRE and JVM, memory areas allocated by JVM, just-in-time compiler, Java platform vs other platforms, classloaders, access modifiers in Java, JDBC, Java API, encapsulation, inheritance, polymorphism and more. A total of 30 questions are presented along with detailed explanations for each.
Introduction to Java programming - Java tutorial for beginners to teach Java ...Duckademy IT courses
Check out the course: https://www.duckademy.com/course/java-programming Learn Java from scratch in an easy and entertaining way. The Easy-to-follow Java programming course on Duckademy was made for beginners. In this course we start at the very basics (from zero) and go through lots of interesting exercises and analogies that will take you to an advanced level. By the end of the course you will have all the knowledge needed to move on and specialize in Java. The course is easy to follow and things are well explained. Furthermore, to make your learning easier and more enjoyable throughout the course we will develop a nostalgic, text-based fantasy game.
The course is recommended to anyone who wants to learn Java. Ideal for those who are new to programming, but it can be useful and enjoyable for people who want to switch to Java from a different programming language.
By the end of the course you will be able to build simple, but fully functional programs. You will also gain all the knowledge needed to specialize in Java and become a well-payed Java expert later on.
Check out the course: https://www.duckademy.com/course/java-programming
The document provides an introduction to the Java programming language. It discusses that Java was originally called Oak and developed by Sun Microsystems in 1991. It can be used to create both applications and applets. The source code is compiled into bytecode, which is then interpreted by the Java Virtual Machine (JVM) to execute programs. Key features of Java include being simple, secure, portable, object-oriented, robust, and multi-threaded. The document also covers concepts such as packages, interfaces, inheritance, method overloading/overriding, and multithreading.
The document provides an overview of object-oriented programming (OOP) concepts and the Java programming language. It discusses key OOP concepts like encapsulation, inheritance, polymorphism and abstraction. It then describes how to write, compile and run a basic Java program. Key aspects of the Java language like classes, objects, methods and constructors are explained. The document also discusses how Java programs are executed using a Java Virtual Machine (JVM).
Mahika Tutorials sharing PPT slide for core java programming language. Go threw this slide and visit our YouTube page too
https://www.youtube.com/c/mahikatutorials
This document provides an overview of the Java programming language as presented by Ms. Surbhi Saroha. It covers topics such as Java overview, data types, control structures, arrays, strings, classes, inheritance, packages, exceptions, and more. The document contains slides with explanations, examples, and code snippets to illustrate key concepts of the Java language.
This document provides information about a student named Mohd. Shahnawaz Alam enrolled in the third semester of a B.Sc. (IT) program. It includes their roll number, book information, and questions about features of Java, executing Java programs, operators in Java, character extraction functions, types of relationships in Java, differences between errors and exceptions, and syntax for FileInputStream and FileOutputStream classes. The document contains detailed responses to each question providing explanations of concepts and code examples.
Java defines data as objects with methods that support the objects. It provides features like abstraction, encapsulation, inheritance and polymorphism. Java programs can be executed on any platform that supports a Java Virtual Machine as Java code is compiled to bytecode, which is platform independent. To execute a Java program, the source code must be compiled to bytecode using the javac compiler, which checks for errors. The bytecode can then be executed using the java command.
The document discusses Java interview questions and answers. It covers topics like the differences between JDK, JRE and JVM, memory areas allocated by JVM, just-in-time compiler, Java platform vs other platforms, classloaders, access modifiers in Java, JDBC, Java API, encapsulation, inheritance, polymorphism and more. A total of 30 questions are presented along with detailed explanations for each.
Introduction to Java programming - Java tutorial for beginners to teach Java ...Duckademy IT courses
Check out the course: https://www.duckademy.com/course/java-programming Learn Java from scratch in an easy and entertaining way. The Easy-to-follow Java programming course on Duckademy was made for beginners. In this course we start at the very basics (from zero) and go through lots of interesting exercises and analogies that will take you to an advanced level. By the end of the course you will have all the knowledge needed to move on and specialize in Java. The course is easy to follow and things are well explained. Furthermore, to make your learning easier and more enjoyable throughout the course we will develop a nostalgic, text-based fantasy game.
The course is recommended to anyone who wants to learn Java. Ideal for those who are new to programming, but it can be useful and enjoyable for people who want to switch to Java from a different programming language.
By the end of the course you will be able to build simple, but fully functional programs. You will also gain all the knowledge needed to specialize in Java and become a well-payed Java expert later on.
Check out the course: https://www.duckademy.com/course/java-programming
Here I discuss about Java programming language and easiest way to solve programming problem. Java basic syntax and their uses are described briefly so that anyone can easily understand within very short time. If anyone follow the slide with proper way,I assure that he or she will find java programming interesting.
This document provides an overview of key concepts in the Java programming language including classes, objects, inheritance, interfaces, packages, exceptions, threads, and more. It discusses how to build standalone Java programs and applets, and covers basic syntax and structures like primitive data types, expressions, control statements, and comments. Methods, constructors, and access modifiers are also explained at a high level.
This document provides an introduction to Java programming and the Java development environment. It discusses what computer programming is, defines the key phases of programming, and presents a simple "Hello World" Java program as an example. It also covers Java concepts like case sensitivity, formatting, and file naming conventions. The document explains how Java code is compiled and executed, and provides an overview of the Java programming language, virtual machine, class files, and class loaders. It introduces the Eclipse integrated development environment and demonstrates how to create a new Java project, write code, compile, run, and debug programs within Eclipse.
Java is an object-oriented programming language introduced in 1995. It is platform independent and used widely for web applications. Java code is compiled into bytecode that runs on a virtual machine, allowing the same code to run on different operating systems. Key features of Java include being simple, object-oriented, platform independent, robust, secure, distributed, multithreaded, and dynamic.
Java is an object-oriented programming language. Key aspects of Java include:
- It is platform independent and runs on a virtual machine.
- Programs are written in classes with methods. The main method is where execution begins.
- Common operations include accepting user input, printing output, and performing math functions.
- Java supports concepts like inheritance, polymorphism, abstraction and encapsulation.
- The language does not support pointers, structures or multiple inheritance.
java: basics, user input, data type, constructorShivam Singhal
The document provides an overview of some key Java concepts including classes, attributes, methods, objects, constructors, and data types. It explains that classes contain attributes and methods, and that objects are instantiated from classes using constructors. It also describes static and non-static methods, with static methods not requiring an object to be called. The main method is used to control program flow. User input can be obtained through command line arguments, Scanner, or BufferedReader classes.
This document provides an introduction to Java programming concepts including:
- Java is both a programming language and platform that is simple, architecture neutral, object-oriented, and portable.
- Java source code is written in .java files and compiled into .class files by javac before being executed by the Java Virtual Machine (JVM).
- The JVM allows Java programs to run on any platform without recompilation, providing platform independence.
- Key Java concepts covered include objects, classes, methods, variables, data types, operators, control flow, and arrays.
- Examples demonstrate how to write, compile, and run simple Java programs to illustrate these core programming concepts.
This document provides an overview of the Java programming language including how it works, its features, syntax, and input/output capabilities. Java allows software to run on any device by compiling code to bytecode that runs on a virtual machine instead of a particular computer architecture. It is an object-oriented language with features like automatic memory management, cross-platform capabilities, and a robust class library.
This document provides information about a Java training module offered by Aims Tutorial, including their contact information, address, and an introduction to Java. It discusses Java's history and features such as being object-oriented, platform independent, simple, secure, architecturally neutral, portable, robust, multi-threaded, dynamic, and high performance. It also covers types of Java applications, different Java technology editions, and compares Java to C++.
In this presentation we introduce topic of core java that is required to learn if you want to be good java programmer. i provide all concept in detail.
This document provides an overview of Java basics, including:
- Java programs are portable across operating systems due to use of byte code, a standardized class library, and language specification.
- Java is secure through features like no pointer arithmetic, garbage collection, and restrictions on applets.
- Java is robust with features like bounds checking and garbage collection that prevent crashes.
- Java programs are either standalone applications or applets that run in a web browser.
- The Java compiler translates source code to byte code, which is then interpreted at runtime.
The document discusses object oriented programming concepts related to exception handling in Java. It covers the benefits of exception handling such as separating error handling code from regular logic and propagating errors up the call stack. It also describes key exception handling constructs like try, catch, throw and throws. The different exception models of termination and resumption are explained along with the exception hierarchy in Java.
This document contains lecture notes on Java programming divided into 6 units. Unit 1 provides an overview of Java and covers data types, variables, arrays, operators, control statements and classes. It also discusses I/O operations like reading console input/output and files. Unit 2 covers string handling and the StringBuffer class. Unit 3 discusses packages, interfaces and exception handling. Unit 4 focuses on multithreading concepts. Unit 5 covers applets, event handling and the Abstract Window Toolkit. Unit 6 introduces Swing and JDBC. The document also includes examples of Java programs and lists lab experiments and reference books.
Java history, versions, types of errors and exception, quiz SAurabh PRajapati
this ppt contains history and basic facts of object oriented programming language java, difference between JIT, JVM, JRE and JDK. it also having information about different versions of java. advantages over other language, difference between error and exception with its types is also included. explanation of final variable and string to int conversation is also added. in the end some twisted question of it which sharpen the knowledge of its basic are added. beyond this some programming examples with output is there too. hope u find it useful...!! thanku..!!
This document provides an overview of the topics covered in a Core Java online training course. The course consists of 12 modules that cover Java fundamentals, OOP concepts, collections, files and I/O, threads, exceptions, JDBC and more. Each module includes topics to be covered and programming sessions to apply the concepts learned through examples and exercises.
This document contains slides from a lecture on Java basics. It covers:
- A brief history of Java and how it works by using bytecode and a Java Virtual Machine for platform independence.
- Java's data types including primitives and classes/objects.
- How to write a simple Java program, compile and run it, and basic program structure.
- Other basics like variables, methods, control structures, and exceptions.
The slides provide examples and explanations of core Java concepts to teach students the fundamentals of the language.
The document provides an overview of the Java programming language. It discusses that Java was developed in the early 1990s by Sun Microsystems. It then summarizes some of Java's main features, including that it is a simple, object-oriented, robust, distributed, platform independent, secured, architecture-neutral, portable, high-performance, multi-threaded, and dynamic language. It also briefly discusses the Java Virtual Machine, Java Runtime Environment, Java Development Kit, Java bytecode, and the main method.
The document introduces abstract data types (ADTs) and common ADT implementations like bags, lists, stacks, queues, dictionaries, and trees. It discusses the history and characteristics of the Java programming language. It provides an example of a simple Java program that prints output and explains the anatomy of a Java program including comments, reserved words, modifiers, statements, blocks, classes, and methods. It also discusses how to get user input in Java using the Scanner class.
The document provides an introduction to Java programming, covering key object-oriented programming concepts like encapsulation, inheritance and polymorphism. It discusses the history and development of Java, comparing it to C++, and outlines core Java concepts such as classes, objects, methods and packages. The document also examines Java features like automatic memory management, type safety and platform independence.
Bt0067 c programming and data structures 1Techglyphs
The document discusses various statements in the C programming language. It defines statement types such as selection/conditional statements (if-else, switch), iteration statements (for, while, do-while), jump statements (break, continue, goto, return), and label statements. It provides examples and explanations of each statement type, including nested if/else statements, the for loop variant forms, and when to use while, do-while, switch, and other statements. It also covers macros and functions in C with definitions and examples.
The document discusses key concepts in object oriented systems including:
1. Cost-benefit analysis with an example of Krag Central Electric Company computerizing its billing system.
2. Risk analysis as part of risk management in software projects.
3. The structure of modern hierarchical programming teams with a team leader and team manager.
4. The synchronize-and-stabilize team organization model used by Microsoft with daily integration of work.
5. The five core workflows of the Unified Process: requirements, analysis, design, implementation, and testing.
Here I discuss about Java programming language and easiest way to solve programming problem. Java basic syntax and their uses are described briefly so that anyone can easily understand within very short time. If anyone follow the slide with proper way,I assure that he or she will find java programming interesting.
This document provides an overview of key concepts in the Java programming language including classes, objects, inheritance, interfaces, packages, exceptions, threads, and more. It discusses how to build standalone Java programs and applets, and covers basic syntax and structures like primitive data types, expressions, control statements, and comments. Methods, constructors, and access modifiers are also explained at a high level.
This document provides an introduction to Java programming and the Java development environment. It discusses what computer programming is, defines the key phases of programming, and presents a simple "Hello World" Java program as an example. It also covers Java concepts like case sensitivity, formatting, and file naming conventions. The document explains how Java code is compiled and executed, and provides an overview of the Java programming language, virtual machine, class files, and class loaders. It introduces the Eclipse integrated development environment and demonstrates how to create a new Java project, write code, compile, run, and debug programs within Eclipse.
Java is an object-oriented programming language introduced in 1995. It is platform independent and used widely for web applications. Java code is compiled into bytecode that runs on a virtual machine, allowing the same code to run on different operating systems. Key features of Java include being simple, object-oriented, platform independent, robust, secure, distributed, multithreaded, and dynamic.
Java is an object-oriented programming language. Key aspects of Java include:
- It is platform independent and runs on a virtual machine.
- Programs are written in classes with methods. The main method is where execution begins.
- Common operations include accepting user input, printing output, and performing math functions.
- Java supports concepts like inheritance, polymorphism, abstraction and encapsulation.
- The language does not support pointers, structures or multiple inheritance.
java: basics, user input, data type, constructorShivam Singhal
The document provides an overview of some key Java concepts including classes, attributes, methods, objects, constructors, and data types. It explains that classes contain attributes and methods, and that objects are instantiated from classes using constructors. It also describes static and non-static methods, with static methods not requiring an object to be called. The main method is used to control program flow. User input can be obtained through command line arguments, Scanner, or BufferedReader classes.
This document provides an introduction to Java programming concepts including:
- Java is both a programming language and platform that is simple, architecture neutral, object-oriented, and portable.
- Java source code is written in .java files and compiled into .class files by javac before being executed by the Java Virtual Machine (JVM).
- The JVM allows Java programs to run on any platform without recompilation, providing platform independence.
- Key Java concepts covered include objects, classes, methods, variables, data types, operators, control flow, and arrays.
- Examples demonstrate how to write, compile, and run simple Java programs to illustrate these core programming concepts.
This document provides an overview of the Java programming language including how it works, its features, syntax, and input/output capabilities. Java allows software to run on any device by compiling code to bytecode that runs on a virtual machine instead of a particular computer architecture. It is an object-oriented language with features like automatic memory management, cross-platform capabilities, and a robust class library.
This document provides information about a Java training module offered by Aims Tutorial, including their contact information, address, and an introduction to Java. It discusses Java's history and features such as being object-oriented, platform independent, simple, secure, architecturally neutral, portable, robust, multi-threaded, dynamic, and high performance. It also covers types of Java applications, different Java technology editions, and compares Java to C++.
In this presentation we introduce topic of core java that is required to learn if you want to be good java programmer. i provide all concept in detail.
This document provides an overview of Java basics, including:
- Java programs are portable across operating systems due to use of byte code, a standardized class library, and language specification.
- Java is secure through features like no pointer arithmetic, garbage collection, and restrictions on applets.
- Java is robust with features like bounds checking and garbage collection that prevent crashes.
- Java programs are either standalone applications or applets that run in a web browser.
- The Java compiler translates source code to byte code, which is then interpreted at runtime.
The document discusses object oriented programming concepts related to exception handling in Java. It covers the benefits of exception handling such as separating error handling code from regular logic and propagating errors up the call stack. It also describes key exception handling constructs like try, catch, throw and throws. The different exception models of termination and resumption are explained along with the exception hierarchy in Java.
This document contains lecture notes on Java programming divided into 6 units. Unit 1 provides an overview of Java and covers data types, variables, arrays, operators, control statements and classes. It also discusses I/O operations like reading console input/output and files. Unit 2 covers string handling and the StringBuffer class. Unit 3 discusses packages, interfaces and exception handling. Unit 4 focuses on multithreading concepts. Unit 5 covers applets, event handling and the Abstract Window Toolkit. Unit 6 introduces Swing and JDBC. The document also includes examples of Java programs and lists lab experiments and reference books.
Java history, versions, types of errors and exception, quiz SAurabh PRajapati
this ppt contains history and basic facts of object oriented programming language java, difference between JIT, JVM, JRE and JDK. it also having information about different versions of java. advantages over other language, difference between error and exception with its types is also included. explanation of final variable and string to int conversation is also added. in the end some twisted question of it which sharpen the knowledge of its basic are added. beyond this some programming examples with output is there too. hope u find it useful...!! thanku..!!
This document provides an overview of the topics covered in a Core Java online training course. The course consists of 12 modules that cover Java fundamentals, OOP concepts, collections, files and I/O, threads, exceptions, JDBC and more. Each module includes topics to be covered and programming sessions to apply the concepts learned through examples and exercises.
This document contains slides from a lecture on Java basics. It covers:
- A brief history of Java and how it works by using bytecode and a Java Virtual Machine for platform independence.
- Java's data types including primitives and classes/objects.
- How to write a simple Java program, compile and run it, and basic program structure.
- Other basics like variables, methods, control structures, and exceptions.
The slides provide examples and explanations of core Java concepts to teach students the fundamentals of the language.
The document provides an overview of the Java programming language. It discusses that Java was developed in the early 1990s by Sun Microsystems. It then summarizes some of Java's main features, including that it is a simple, object-oriented, robust, distributed, platform independent, secured, architecture-neutral, portable, high-performance, multi-threaded, and dynamic language. It also briefly discusses the Java Virtual Machine, Java Runtime Environment, Java Development Kit, Java bytecode, and the main method.
The document introduces abstract data types (ADTs) and common ADT implementations like bags, lists, stacks, queues, dictionaries, and trees. It discusses the history and characteristics of the Java programming language. It provides an example of a simple Java program that prints output and explains the anatomy of a Java program including comments, reserved words, modifiers, statements, blocks, classes, and methods. It also discusses how to get user input in Java using the Scanner class.
The document provides an introduction to Java programming, covering key object-oriented programming concepts like encapsulation, inheritance and polymorphism. It discusses the history and development of Java, comparing it to C++, and outlines core Java concepts such as classes, objects, methods and packages. The document also examines Java features like automatic memory management, type safety and platform independence.
Bt0067 c programming and data structures 1Techglyphs
The document discusses various statements in the C programming language. It defines statement types such as selection/conditional statements (if-else, switch), iteration statements (for, while, do-while), jump statements (break, continue, goto, return), and label statements. It provides examples and explanations of each statement type, including nested if/else statements, the for loop variant forms, and when to use while, do-while, switch, and other statements. It also covers macros and functions in C with definitions and examples.
The document discusses key concepts in object oriented systems including:
1. Cost-benefit analysis with an example of Krag Central Electric Company computerizing its billing system.
2. Risk analysis as part of risk management in software projects.
3. The structure of modern hierarchical programming teams with a team leader and team manager.
4. The synchronize-and-stabilize team organization model used by Microsoft with daily integration of work.
5. The five core workflows of the Unified Process: requirements, analysis, design, implementation, and testing.
The document discusses various logic gates and flip flops. It begins by explaining the AND, OR, and NOT gates as the fundamental logic gates. It then discusses the JK flip flop, explaining its operation and how it can be used to create counters. It also briefly discusses the SR flip flop and D flip flop. The document provides truth tables and diagrams to illustrate the working of these logic components.
The document discusses several topics related to computers and information technology:
1) It summarizes the goals of the Fifth Generation Computer Systems project in Japan to create a new "fifth generation" computer using parallel processing.
2) It explains what an Arithmetic Logic Unit (ALU) is and its important role in the central processing unit (CPU) of performing arithmetic and logical operations.
3) It distinguishes between application software and system software, with application software designed for specific tasks and system software involved in integrating computer capabilities.
A parallel-in parallel-out shift register is designed to take in parallel data, shift it internally, and then output the shifted data in parallel. The design uses D flip-flops connected in a loop so that on each clock pulse, the data is shifted one position to the left or right. Mode control inputs determine the direction of shifting and whether the data is loaded in parallel or shifted serially. The design allows cascading multiple shift registers together to process more data bits.
A modulo-n counter is designed using D flip-flops to count from 0 to N-1 and then reset back to 0. The design is refined through steps like structural refinement to separate the counter and controller, interface refinement to
The document discusses relational algebra operators and their composition. It explains that relational algebra operators return relations, so their outputs can be used as inputs to other operators, allowing operator composition. This ability to compose operators is important because it allows complex queries to be built by combining multiple simple operations.
The document discusses the benefits of making the system catalogs in a relational database management system (RDBMS) as relations (tables). This approach stores schema metadata and internal bookkeeping information in relational tables and views, as advocated by the RDBMS. It allows all metadata to be made available through catalog views, which present metadata independently of the underlying implementation and are unaffected by catalog table changes. Catalog views provide the most efficient and standardized way to access core server metadata and help with query optimization.
The document discusses the Open Grid Services Architecture (OGSA). It provides definitions and explanations of key concepts in OGSA including:
- OGSA defines standard protocols and formats to build large-scale, interoperable grid systems based on services.
- The Open Grid Services Infrastructure (OGSI) provides a specification for implementing grid services as stateful web services.
- Some major goals of OGSA are identifying use cases, core platform components, and defining models and profiles for interoperable solutions.
- Security is a key challenge in grid environments due to the need for integration with existing systems, interoperability across different hosting environments, and managing dynamic trust relationships.
Grid computing is a model of distributed computing that uses geographically and administratively disparate resources to solve large problems. It involves sharing computing power, data, and other resources across organizational boundaries. Key aspects include applying resources from many computers to a single problem, combining resources from multiple administrative domains for tasks requiring large processing power or data, and using middleware to coordinate resources as a virtual system. The document then discusses definitions of grid computing from various organizations and the core functional requirements and characteristics needed for grid applications and users.
Bt0067 c programming and data structures2Techglyphs
The document discusses various data structures and file input/output functions in C programming. It defines pointers and their advantages, describes the fread() function syntax, differentiates between linear and nonlinear data structures, discusses stack applications and operations, defines linked lists and their operations, and provides examples for each topic.
1) A database is a structured collection of records or data that is stored in a computer system and allows for easy storage, retrieval, and maintenance of data. It must store large amounts of information and allow for easy access and input of new data.
2) There are different views available in PowerPoint for presenting information, including Normal view, Slide Sorter view, Notes Page view, and Slide Show view.
3) Media refers broadly to various means of communication, but in computers specifically refers to different types of data storage like hard drives, removable drives, CDs, DVDs, flash drives, and networks that connect workstations.
1) Data flow diagrams (DFDs) are graphical representations that show how data moves through an information system. DFDs depict incoming and outgoing data flows and stored data.
2) There are two types of DFDs - logical DFDs focus on system processes and data flow, while physical DFDs are more specific and show how data flow is implemented.
3) DFDs use various symbols like rectangles, circles, and arrows to represent entities, processes, data storage, and data flow respectively. DFDs can have multiple levels that break down the system into more detailed modules and processes.
The document discusses Java programming concepts including:
- Java provides a common framework to handle strings, networks, and extended functions. It also handles garbage collection and can be cross-platform.
- The main() method is where every Java program begins execution. It must have a specific signature of public static void main(String[] args).
- There are 8 primitive data types in Java including int, short, long, float, double, char, boolean, and byte that are used to store basic values.
20 most important java programming interview questionsGradeup
The document discusses 20 important Java programming interview questions. It covers topics such as the differences between interfaces and abstract classes, when to use abstract classes versus interfaces, what the Serializable interface does, how to force garbage collection, the differences between StringBuffer and StringBuilder, checked and unchecked exceptions, how Java allocates stack and heap memory, Java reflection, the Java Virtual Machine, the differences between JDK and JRE, and more.
This document appears to be an assignment submission cover page for a student named Narinder Kumar studying MCA at Sikkim Manipal University. It provides details of the assignment such as the course, subject, semester, and date of submission. The document contains the student's responses to 5 questions on Java programming concepts and features.
Object-Oriented Programming with Java UNIT 1SURBHI SAROHA
This document provides an introduction and syllabus for an Object-Oriented Programming with Java course. The syllabus covers key Java concepts like keywords, variables, data types, operators, decision making, classes, objects, methods, inheritance, and arrays. It also describes the importance and features of Java, including being platform independent, secure, portable, robust, and high performance. The document includes code examples for a first Java program and demonstrates various operators.
Java Faqs useful for freshers and experiencedyearninginjava
1. The document discusses the differences between abstract classes and interfaces in Java. Abstract classes can contain implemented methods while interfaces contain no implementation code. A class can extend only one abstract class but implement multiple interfaces.
2. It defines checked and unchecked exceptions in Java. Checked exceptions must be caught or declared to be thrown, while unchecked exceptions like NullPointerException do not require handling.
3. User-defined exceptions can be created by extending the Exception class and using throw statements. The throw statement signals the exception and catch handles it.
Top 371 java fa qs useful for freshers and experiencedGaurav Maheshwari
The document discusses differences between abstract classes and interfaces in Java. It provides 7 key differences: 1) Abstract classes can have executable and unimplemented methods while interfaces only contain method signatures. 2) A class can implement multiple interfaces but extend only one abstract class. 3) Abstract classes can have non-abstract methods and variables while interfaces cannot. 4) Abstract classes can define constructors while interfaces cannot. 5) Abstract classes can have any visibility modifier while interfaces must be public or package-private. 6) Abstract classes inherit from Object while interfaces do not.
This document provides an overview of an introductory Java programming textbook. It outlines the course objectives which are to understand basic Java concepts like data types, control flow, methods and arrays. It describes the book's organization into parts covering fundamentals, object-oriented programming, GUI programming and comprehensive projects. Each part is broken down into chapters covering specific Java topics.
This document provides an overview of an introductory Java programming textbook. It outlines the course objectives which are to understand basic Java concepts like data types, control flow, methods and arrays. It describes the book's organization into parts covering fundamentals, object-oriented programming, GUI programming and comprehensive projects. Each part is broken down into chapters covering specific Java topics.
This document provides summaries of common Java interview questions. It discusses the differences between abstract classes and interfaces, checked and unchecked exceptions, user-defined exceptions, differences between C++ and Java, Java statements, JAR files, JNI, serialization, null interfaces, synchronized methods, singleton classes, compilation units, resource bundles, transient variables, the Collection API, iterators, observers and observables, synchronization, locks on classes, thread states, anonymous classes, primitive data types and their ranges.
This document provides an overview of Java including its origins from C and C++, how it achieves platform independence through bytecode compilation, and key features such as being object-oriented, garbage collected, robust, secure, extensible, and well-understood. It also discusses object-oriented programming concepts in Java like encapsulation, polymorphism through method overloading and overriding, and the importance of Java for internet applications like applets.
The document provides an overview of the Samsung University Program and key concepts related to Java programming including:
1. Java is an object-oriented, platform independent programming language that is robust, secure, and supports multithreading.
2. The key concepts of object-oriented programming in Java include encapsulation, inheritance, polymorphism, and abstraction.
3. Java applications are compiled into bytecode that can run on any system with a Java Virtual Machine, allowing programs to be "write once, run anywhere."
Java is a compiled and interpreted, platform-independent, secure, robust, and object-oriented programming language. It is compiled into bytecode that can run on any Java Virtual Machine (JVM), making programs portable across platforms. The JVM is available on many operating systems, so Java code can run on Windows, Linux, Solaris, or Mac OS. Java uses automatic memory management, exceptions, and avoids many common programming bugs found in other languages like C/C++.
Java was created in 1991 by James Gosling, Mike Sheridan, and Patrick Naughton at Sun Microsystems. It has three editions: Java ME for limited devices, Java SE as the core platform for desktops and servers, and Java EE for large enterprise applications. Java code is compiled into bytecode that runs on a Java Virtual Machine (JVM) making Java portable across platforms. Key principles of Java include being object-oriented, secure, and platform independent.
Synchronization in Java controls access to shared resources by multiple threads so that only one thread can access a resource at a time. The JVM interprets bytecode, making Java platform independent. Interfaces define methods for classes to implement, while abstract classes can include implementations along with abstract methods. Autoboxing converts primitives to wrapper types for object-oriented operations, while unboxing converts wrappers back to primitives.
This document provides information about Java programming questions that are commonly asked in interviews and exams. It lists 30 Java programming questions and their answers on topics like OOPs concepts, multithreading, exceptions, JDBC, serialization and more. The document also provides links to connect with the authors on social media and messaging platforms like WhatsApp, Telegram, Facebook, Twitter etc. for any doubts or feedback. It reminds the reader to practice all the questions well to build a clear understanding of concepts and score well in exams.
This document provides information on performing object-oriented analysis and design in Java technology. It outlines the basics of the Java language that should be applied, including creating executable applications, using packages, data types, operators, decision constructs, arrays, and loop constructs. It also describes the learning outcomes, methodology, and assessment approach for this competency.
Many students reach out to me asking for project ideas they can do as a summer project for learning. Here is an interesting project idea - implement your own java disassembler (and expand it to a VM later).
This document provides an overview of key concepts in Java programming including:
- Creating, compiling, and running Java programs and understanding program anatomy such as comments, packages, classes, and methods.
- Using basic programming constructs like data types, control statements, and arrays to write simple Java programs.
- Establishing a foundation in Java concepts such as Object Oriented Programming (OOP) and establishing a firm understanding of how Java code is structured and executed.
- Learning how to use core Java APIs and frameworks like I/O, Collections, Threads, Reflection, Serialization, Networking, RMI, and JDBC.
Constructors cannot be made final as they are needed to create object instances and initialize class data. Constructors are similar to methods but cannot be directly invoked via method calls. The APK file format is an Android application package used for distribution and installation of Android apps. It is a zip file containing compiled code, resources, manifest, and other assets. Java is a popular object-oriented programming language that is portable and platform independent due to its compile-once-run-anywhere nature.
Bt0068 computer organization and architecture Techglyphs
The document discusses several topics related to computer organization and architecture. It begins by providing examples of converting decimal numbers to binary. It then explains one stage of logic circuits using AND, OR, XOR, and complement gates. It describes the Von Neumann architecture, including its five classical components and the concept of the Von Neumann bottleneck. Finally, it discusses the register organization of several microprocessors including the 8085, Z8000, and MC68000, comparing their register sets, address buses, and data buses.
Bt0068 computer organization and architecture 2Techglyphs
1. The document discusses various data types and number representations used in computer systems, including integers, floating point numbers, arrays, strings, and opaque data.
2. Integer representations include signed and unsigned integers stored in 32-bit two's complement format. Floating point numbers use the IEEE 754 standard for single and double precision numbers, representing the sign, exponent, and significand fields.
3. Common number systems like binary, hexadecimal, and octal are described along with their relationships. Gray code is also introduced as a way to represent successive values that differ in only one bit.
This document discusses several topics related to operating systems:
1. It explains multiprogramming and how operating systems can interrupt processes to share resources between multiple concurrent programs or users.
2. It describes three types of schedulers in operating systems - long-term, mid-term, and short-term schedulers - and their functions in admitting, swapping, and allocating CPU time to processes.
3. It discusses the First Come First Served scheduling algorithm and its properties of being simple but potentially resulting in long wait times.
The document discusses several topics related to operating systems:
1. It explains how virtual addresses are mapped to physical addresses using page tables, where a virtual address is split into a virtual page number and offset, and the page table converts the virtual page number to a physical page number.
2. It discusses the optimal page replacement algorithm, which replaces the page that will not be used farthest in the future.
3. It defines a file system as a method for organizing and storing computer files using a storage device divided into sectors organized into files and directories.
The document provides an overview of the ISO OSI model and its 7 layers, describing the functions of each layer. It then discusses several topics related to computer networks, including the ISO/OSI model (layers and functions), ISDN (architecture and usage), LAN protocols (such as Ethernet), framing in the data link layer and its importance, and the IEEE 802.11 wireless networking standard.
This document discusses various topics related to computer networking including routing, addressing schemes, congestion control, remote procedure calls, simple mail transfer protocol, static routing algorithms, IPv4 addressing, and session layer design issues. It provides definitions and explanations of static and dynamic routing, differentiates between IPv4 and IPv6 addressing, describes congestion and congestion control, discusses the importance and workings of remote procedure calls, provides a detailed explanation of SMTP, explains two static routing algorithms (Dijkstra's algorithm and flooding algorithm), discusses IPv4 addressing schemes, describes congestion avoidance in the transport layer, and discusses design issues of the session layer such as dialog control.
This document discusses features of MySQL including security, scalability and limits, connectivity, and localization. It provides examples of SQL statements using SELECT, JOINs, subqueries, and transaction statements like SAVEPOINT and ROLLBACK TO SAVEPOINT. Key points covered include the differences between CHAR and VARCHAR data types, index operations in MySQL, and string and full-text search functions.
This document discusses various SQL statements and concepts. It begins by explaining how to connect to a MySQL server by specifying a host name, user name, and password. It then defines float and double data types and their properties. The rest of the document discusses ALTER DATABASE syntax, INSERT statements, UNION, DELETE, UPDATE syntax, correlated subqueries with an example, comparison operators, logical operators, encryption functions, transactional statements that cause implicit commits, and DECLARE statements.
1. Multimedia refers to the combination of different content forms such as text, sound, still images, animation, video, or interactivity content forms. It allows for interactive user engagement.
2. The document discusses the basic elements of drawing including point, line, shape, tone, plane, texture, color, mass, and space. It provides examples to explain each element.
3. Inverted symmetry in design refers to a mirror image where half of the image is inverted like a playing card. It applies the principle of symmetry but with one half inverted.
The document discusses website design and validation tools, style sheets, XML tools, and sending and receiving SOAP messages. It provides details on:
1) Total Validator, a free tool that validates HTML, accessibility, spelling, and broken links and takes screenshots in different browsers.
2) How style sheets can support multiple browsers by using different style sheet documents customized for each browser or detecting the browser with JavaScript.
3) SOAP uses an envelope and body structure to send remote procedure calls with parameters and receive responses. It provides an example request and response to a weather service.
The document defines and explains various elements of multimedia including text, graphics, sound, video, and animation. It also defines and describes drawing, color, fonts, and briefly explains the basic laws of design such as balance, rhythm, emphasis, and unity.
The document discusses the architecture of web pages, including HTML for encoding content, URLs for naming objects, and HTTP for transferring information. It also discusses requirements for internet connections such as a computer, client programs, and a connection method like dial-up, DSL, or satellite. Frames allow dividing the browser window into rectangular areas for displaying multiple documents, with the <frameset> tag specifying the layout and <frame> tags embedding each document. CDATA sections are used to escape text that would otherwise be parsed as markup. List and union data types in XML allow defining structures for lists of items or merging the values of multiple types.
The document discusses the characteristics of algorithms and the concept of mathematical expectation in average case analysis. It then provides the pseudocode for the MaxMin algorithm and discusses the greedy knapsack algorithm and the travelling salesman problem. Finally, it explains the sum of subsets problem, describing two formulations and how the solution space can be organized into trees.
This document discusses branch and bound algorithms and NP-hard and NP-complete problems. It provides examples and proofs related to these topics.
1) Branch and bound is an algorithm that systematically enumerates candidate solutions by discarding subsets that are provably suboptimal. The knapsack problem is used as an example problem.
2) NP-hard and NP-complete problems are those whose best known algorithms run in non-polynomial time. If a problem can be solved in polynomial time, then all NP-complete problems can be. Proving problems NP-complete involves reducing other known NP-complete problems to the target problem.
3) Trees are connected graphs without cycles. They are used to represent hierarchies and
The document discusses various topics related to software engineering including:
1) How early days of software development have affected modern practices.
2) Definitions of software engineering from different sources.
3) The stages of software design including problem analysis, solution identification, and abstraction description.
4) Object-oriented design principles like information hiding, independent objects, and service-based communication.
This document describes concepts related to working with data in Visual Basic .NET, including:
1. Setting a connection string involves specifying the data provider technology and data source location in the ConnectionString property of a Connection object, separated by a semicolon. An example connects to an Access database on the C drive.
2. Record navigation in a DataSet can be done by incrementing or decrementing a counter variable and calling a NavigateRecords subroutine. Buttons can move to the first, last, previous, and next records.
3. Arrays can be fixed-size or dynamic. Fixed arrays have a set size declared while dynamic arrays can be resized at runtime using ReDim. Multidimensional arrays
The document discusses different types of software assessment techniques, including metric-oriented assessments, unified model assessments, process improvement assessments, and tool support assessments. It also covers the importance of version and release management in tracking different versions of a system. Finally, it discusses various software testing fundamentals, strategies, and principles, such as unit testing, integration testing, validation testing, stress testing, and the importance of designing software for testability.
The document discusses Visual Basic .NET and the .NET framework. It describes how the .NET framework defines the environment for executing VB.NET applications and services that can be used within applications. It also discusses how Visual Studio includes components like the Microsoft Development Environment and Microsoft SQL Server 2000 Desktop Engine that make it an outstanding development product. Finally, it explains that Visual Studio .NET is a suite of products that includes programming languages like Visual Basic, C#, and C++ for developing applications.
Strategies for Effective Upskilling is a presentation by Chinwendu Peace in a Your Skill Boost Masterclass organisation by the Excellence Foundation for South Sudan on 08th and 09th June 2024 from 1 PM to 3 PM on each day.
Exploiting Artificial Intelligence for Empowering Researchers and Faculty, In...Dr. Vinod Kumar Kanvaria
Exploiting Artificial Intelligence for Empowering Researchers and Faculty,
International FDP on Fundamentals of Research in Social Sciences
at Integral University, Lucknow, 06.06.2024
By Dr. Vinod Kumar Kanvaria
How to Add Chatter in the odoo 17 ERP ModuleCeline George
In Odoo, the chatter is like a chat tool that helps you work together on records. You can leave notes and track things, making it easier to talk with your team and partners. Inside chatter, all communication history, activity, and changes will be displayed.
How to Setup Warehouse & Location in Odoo 17 InventoryCeline George
In this slide, we'll explore how to set up warehouses and locations in Odoo 17 Inventory. This will help us manage our stock effectively, track inventory levels, and streamline warehouse operations.
This presentation was provided by Steph Pollock of The American Psychological Association’s Journals Program, and Damita Snow, of The American Society of Civil Engineers (ASCE), for the initial session of NISO's 2024 Training Series "DEIA in the Scholarly Landscape." Session One: 'Setting Expectations: a DEIA Primer,' was held June 6, 2024.
Walmart Business+ and Spark Good for Nonprofits.pdfTechSoup
"Learn about all the ways Walmart supports nonprofit organizations.
You will hear from Liz Willett, the Head of Nonprofits, and hear about what Walmart is doing to help nonprofits, including Walmart Business and Spark Good. Walmart Business+ is a new offer for nonprofits that offers discounts and also streamlines nonprofits order and expense tracking, saving time and money.
The webinar may also give some examples on how nonprofits can best leverage Walmart Business+.
The event will cover the following::
Walmart Business + (https://business.walmart.com/plus) is a new shopping experience for nonprofits, schools, and local business customers that connects an exclusive online shopping experience to stores. Benefits include free delivery and shipping, a 'Spend Analytics” feature, special discounts, deals and tax-exempt shopping.
Special TechSoup offer for a free 180 days membership, and up to $150 in discounts on eligible orders.
Spark Good (walmart.com/sparkgood) is a charitable platform that enables nonprofits to receive donations directly from customers and associates.
Answers about how you can do more with Walmart!"
it describes the bony anatomy including the femoral head , acetabulum, labrum . also discusses the capsule , ligaments . muscle that act on the hip joint and the range of motion are outlined. factors affecting hip joint stability and weight transmission through the joint are summarized.
This slide is special for master students (MIBS & MIFB) in UUM. Also useful for readers who are interested in the topic of contemporary Islamic banking.
LAND USE LAND COVER AND NDVI OF MIRZAPUR DISTRICT, UPRAHUL
This Dissertation explores the particular circumstances of Mirzapur, a region located in the
core of India. Mirzapur, with its varied terrains and abundant biodiversity, offers an optimal
environment for investigating the changes in vegetation cover dynamics. Our study utilizes
advanced technologies such as GIS (Geographic Information Systems) and Remote sensing to
analyze the transformations that have taken place over the course of a decade.
The complex relationship between human activities and the environment has been the focus
of extensive research and worry. As the global community grapples with swift urbanization,
population expansion, and economic progress, the effects on natural ecosystems are becoming
more evident. A crucial element of this impact is the alteration of vegetation cover, which plays a
significant role in maintaining the ecological equilibrium of our planet.Land serves as the foundation for all human activities and provides the necessary materials for
these activities. As the most crucial natural resource, its utilization by humans results in different
'Land uses,' which are determined by both human activities and the physical characteristics of the
land.
The utilization of land is impacted by human needs and environmental factors. In countries
like India, rapid population growth and the emphasis on extensive resource exploitation can lead
to significant land degradation, adversely affecting the region's land cover.
Therefore, human intervention has significantly influenced land use patterns over many
centuries, evolving its structure over time and space. In the present era, these changes have
accelerated due to factors such as agriculture and urbanization. Information regarding land use and
cover is essential for various planning and management tasks related to the Earth's surface,
providing crucial environmental data for scientific, resource management, policy purposes, and
diverse human activities.
Accurate understanding of land use and cover is imperative for the development planning
of any area. Consequently, a wide range of professionals, including earth system scientists, land
and water managers, and urban planners, are interested in obtaining data on land use and cover
changes, conversion trends, and other related patterns. The spatial dimensions of land use and
cover support policymakers and scientists in making well-informed decisions, as alterations in
these patterns indicate shifts in economic and social conditions. Monitoring such changes with the
help of Advanced technologies like Remote Sensing and Geographic Information Systems is
crucial for coordinated efforts across different administrative levels. Advanced technologies like
Remote Sensing and Geographic Information Systems
9
Changes in vegetation cover refer to variations in the distribution, composition, and overall
structure of plant communities across different temporal and spatial scales. These changes can
occur natural.
2. 2
1.What is bytecode? Explain.
Java is both interpreted and compiled. The code is complied to
a bytecode that is binary and platform independent. When the
program has to be executed, the code is fetched into the memory
and interpreted on the user’s machine. As an interpreted language,
Java has simple syntax.
When you compile a piece of code, all errors are listed together. You
can execute only when all the errors are rectified. An interpreter, on
the other hand, verifies the code and executes it line by line. Only
when the execution reaches the statement with error, the error is
reported. This makes it easy for a programmer to debug the code.
The drawback is that this takes more time than compilation.
Compilation is the process of converting the code that you
type, into a language that the computer understands – machine
language. When you compile a program using a compiler, the compiler
checks for syntactic errors in code and list all the errors on the
screen. You have to rectify the errors and recompile the program to
get the machine language code. The Java compiler compiles the code
to a bytecode that is understood by the Java environment.Bytecode is
the result of compiling a Java program. You can execute this code on
any platform. In other words, due to the bytecode compilation
process and interpretation by a browser, Java programs can be
executed on a variety of hardware and operating systems. The only
requirement is that the system should have a Java-enabled Internet
browser.
3. 3
The Java interpreter can execute Java code directly on any
machine on which a Java interpreter has been installed.a Java program
can run on any machine that has a Java interpreter. The bytecode
supports connection to multiple databases. Java code is portable.
Therefore, others can use the programs that you write in Java, even
if they have different machines with different operating systems.
Bytecode is a highly optimized set of
instructions designed to be executed by the Java run-time system,
which is called the Java Virtual Machine (JVM). That is, in its
standard form, the JVM is an interpreter for bytecode. This may
come as a bit of surprise.Translating a Java program into bytecode
helps it to run much easier in a wide variety of environments. The
reason is straightforward: only the JVM needs to be implemented for
each platform. Once the run-time package exists for a given system,
any Java program can run on it. Remember, although the details of
the JVM will differ from platform to platform, all interpret the same
Java bytecode. If a Java program was compiled to native code, then
different versions of the same program should exist for each type of
CPU connected to the Internet. This is, of course, not a feasible
solution. Thus, the interpretation of bytecode is the easiest way to
create truly portable programs.
2. How do you compile a Java program?
The programs that you write in Java should be saved in a
file, which has the following name format:
4. 4
<class_name>.java
Compiling
A program is a set of instructions. In order to execute a program,
the operating system needs to understand the language. The only
language an operating system understands is in terms of 0’s and 1’s
i.e. the binary language. Programs written in language such as C and
C++ are converted to binary code during the compilation process.
However, that binary code can be understood only by the operating
system for which the program is compiled. This makes the program or
application as operating system dependent.
In Java, the program is compiled into bytecode (.class file) that run
on the Java Virtual Machine, which can interpret and run the program
on any operating system. This makes Java programs platform-
independent.
At the command prompt, type
javac <filename>.java
to compile the Java program.
5. 5
3. What do you mean by operator precedence?
When more than one operator is used in an expression,
Java will use operator precedence rule to determine the order in
which the operators will be evaluated. For example, consider the
following expression:
Result=10+5*8-15/5
In the above expression, multiplication and division operations have
higher priority over the addition and subtraction. Hence they are
performed first. Now, Result = 10+40-3.
Addition and subtraction has the same priority. When the operators
are having the same priority, they are evaluated from left to right in
the order they appear in the expression. Hence the value of the
result will become 47. In general the following priority order is
followed when evaluating an expression:
· Increment and decrement operations.
· Arithmetic operations.
· Comparisons.
· Logical operations.
· Assignment operations.
6. 6
To change the order in which expressions are evaluated, parentheses
are placed around the expressions that are to be evaluated first.
When the parentheses are nested together, the expressions in the
innermost parentheses are evaluated first. Parentheses also improve
the readability of the expressions. When the operator precedence is
not clear, parentheses can be used to avoid any confusion.
4. What is an array? Explain with examples.
An array represents a number of variables which occupy
contiguous spaces in the memory. Each element in the array is
distinguished by its index. All elements in an array must be of the
same data type. For example, you cannot have one element with int
data type and another belonging to the boolean data type in the
same array. An array is a collection of elements of the same type
that are referenced by a common name. Each element of an array can
be referred to by an array name and a subscript or index. To create
and use an array in Java, you need to first declare the array and
then initialize it. The syntax for creating an array is:
7. 7
data- type [ ] variablename;
Example:
int [ ] numbers;
The above statement will declare a variable that can hold an array of
int type variables. After declaring the variable for the array, the
array needs to be allocated in memory. This can be done using the
new operator in the following way:
numbers = new int [10];
This statement assigns ten contiguous memory locations of the type
int to the variable numbers. The array can store ten elements.
Iteration can be used to access all the elements of the array, one by
one.
5. How will you implement inheritance in Java?
8. 8
Inheritance can create a general class that defines traits
common to a set of related items. This class can then be inherited by
other, more specific classes, each adding those things that are unique
to it. In the terminology of Java, a class that is inherited is called a
superclass. The class that does the inheriting is called a subclass.
Therefore, a subclass is a specialized version of a superclass. Java
provides a mechanism for partitioning the class name space into more
manageable chunks. This mechanism is the package. The package is
both a naming and a visibility control mechanism. You can define
classes inside a package that are not accessible by code outside that
package. You can also define class members that are only exposed to
other members of the same package. Using the keyword interface,
Inheritance is one of the
cornerstones of object-oriented programming, because it allows the
creation of hierarchical classifications. Using inheritance, you can
create a general class that defines traits common to a set of related
items. This class can then be inherited by other, more specific classes,
each adding those things that are unique to it. In the terminology of
Java, a class that is inherited is called a superclass. The class that
does the inheriting is called a subclass. Therefore, a subclass is a
specialized version of a superclass. It inherits all of the instance
variables and methods defined by the superclass and add its own,
unique elements.
The extends keyword is used to derive a class from a
superclass, or in other words, extend the functionality of a
superclass.
Syntax
public class <subclass_name> extends <superclass_name>
9. 9
Example
public class Confirmed extends Ticket
{
}
Rules for Overriding Methods
· The method name and the order of arguments should be identical
to that of the superclass method.
· The return type of both the methods must be the same.
· The overriding method cannot be less accessible than the method it
overrides. For example, if the method to override is declared as
public in the superclass, you cannot override it with the private
keyword in the subclass.
· An overriding method cannot raise more exceptions than those
raised by the superclass.
6. Explain different kinds of Exceptions in Java.
10. 10
The term exception denotes an exceptional event. It
can be defined as an abnormal event that occurs during program
execution and disrupts the normal flow of instruction.
The class at the top of the exception classes hierarchy is Throwable
class. Two classes are derived from the Throwable class – Error and
Exception. The Exception class is used for the exceptional conditions
that has to be trapped in a program. The Error class defines a
condition that does not occur under normal circumstances. In other
words, the Error class is used for catastrophic failures such as
VirtualMachineError
Java has several predefined exceptions. The most common
exceptions that you may encounter are described below.
· Arithmetic Exception
This exception is thrown when an exceptional arithmetic condition has
occurred. For example, a division by zero generates such an
exception.
· NullPointer Exception
This exception is thrown when an application attempts to use null
where an object is required. An object that has not been allocated
memory holds a null value. The situations in which an exception is
thrown include:
11. 11
- Using an object without allocating memory for it.
- Calling the methods of a null object.
- Accessing or modifying the attributes of a null object.
· ArrayIndexOutOfBounds Exception
This exception is thrown when an attempt is made to access an array
element beyond the index of the array. For example, if you try to
access the eleventh element of an array that has only ten elements,
the exception will be thrown.
7. What are the uses of stream class?
Stream Classes are classified as FileInputStream,
FileOutputStream, BufferedInputStream, BufferedOutputStream,
DataInputStream, and DataOutputStream classes.
The FileInputStream and FileOutputStream Classes
These streams are classified as mode streams as they read and write
data from disk files. The classes associated with these streams have
constructors that allow you to specify the path of the file to which
they are connected. The FileInputStream class allows you to read
input from a file in the form of a stream. The FileOutputStream
class allows you to write output to a file stream.
Example:
FileInputStream inputfile = new FileInputStream (“Employee.dat”);
12. 12
FileOutputStream outputfile = new FileOutputStream (“binus.dat”);
The BufferedInputStream and BufferedOutputStream Classes
The BufferedInputStream class creates and maintains a buffer for an
input stream. This class is used to increase the efficiency of input
operations. This is done by reading data from the stream one byte at
a time. The BufferedOutputStream class creates and maintains a
buffer for the output stream. Both the classes represent filter
streams.
The DataInputStream and DataOutputStream Classes
The DataInputStream and DataOutputStream classes are the filter
streams that allow the reading and writing of Java primitive data
types.
The DataInputStream class provides the capability to read primitive
data types from an input stream. It implements the methods presents
in the DataInput interface.
8. What is AWT? Explain.
The Abstract Windowing Toolkit, also called as AWT is a
set of classes, enabling the user to create a user friendly, Graphical
User Interface (GUI). It will also facilitate receiving user input
from the mouse and keyboard. The AWT classes are part of the
13. 13
java.awt package. The user interface consists of the following three:
· Components – Anything that can be put on the user interface. This
includes buttons, check boxes, pop-up menus, text fields, etc.
· Containers – This is a component that can contain other
components.
· Layout Manager – These define how the components will be
arranged in a container.
The statement import java.awt.*; imports all the components,
containers and layout managers necessary for designing the user
interface.
The AWT supplies the following components.
· Labels (java.awt.Label)
· Buttons (java.awt.Button)
· Checkboxes (java.awt.Checkbox)
· Single- line text field (java.awt.TextField)
· Larger text display and editing areas (java.awt.TextArea)
· Pop-up lists of choices (java.awt.Choice)
· Lists (java.awt.List)
· Sliders and scrollbars (java.awt.Scrollbar )
· Drawing areas (java.awt.Canvas)
· Menus (java.awt.Menu, java.awt.MenuItem,
java.awt.CheckboxMenuItem )
· Containers (java.awt.Panel, java.awt.Window and its subclasses)
14. 14
9. What are the different components of an event?
An event comprises of three components:
· Event Object – When the user interacts with the application by
pressing a key or clicking a mouse button, an event is generated. The
operating system traps this event and the data associated with it, for
example, the time at which the event occurred, the event type (like a
keypress or a mouseclick). This data is then passed on to the
application to which the event belongs.
In Java, events are represented by objects that describe the events
themselves. Java has a number of classes that describe and handle
different categories of event.
· Event Source – An event source is an object that generates an
event. For example, if you click on a button, an ActionEvent object
is generated. The object of the ActionEvent class contains
information about the event.
· Event-handler – An event-handler is a method that understands
the event and processes it. The event-handler method takes an event
object as a parameter.
15. 15
10.Draw and explain the JDBC Application Architecture.
Connection to a Database
The java.sql package contains classes that help in connecting to a
16. 16
database, sending SQL statements to the database, and processing
query results.
The Connection Objects
The Connection object represents a connection with a database. You
may have several Connection objects in an application that connects to
one or more databases.
Loading the JDBC-ODBC Bridge and Establishing Connection
To establish a connection with a database, you need to register the
ODBC-JDBC Driver by calling the forName() method from the Class
class and then calling the getConnection() method from the
DriverManager class.
The getConnection() method of the DriverManager class attempts
to locate the driver that can connect to the database represented by
the JDBC URL passed to the getConnection() method.
The JDBC URL
The JDBC URL is a string that provides a way of identifying a
database. A JDBC URL is divided into three parts:
<protocol>:<subprotocol>:<subname>
· <protocol> in a JDBC URL is always jdbc.
· <subprotocol> is the name of the database connectivity mechanism.
If the mechanism of retrieving the data is ODBC-JDBC bridge, the
subprotocol must be odbc.
· <subname> is used to identify the database.
Example: JDBC URL
String url = “jdbc:odbc:MyDataSource”;
17. 17
Class.forName (“sun.jdbc.odbc.JdbcOdbcDriver“);
Connection con = DriverManager.getConnection(url);
Using the Statement Object You can use the statement object to
send simple queries to the database as shown in the sample QueryApp
program.
The Statement object allows you to execute simple queries. It has
the following three methods that can be used for the purpose of
querying:
§ The executeQuery() method executes a simple query and returns a
single ResultSet object.
§ The executeUpdate() method executes an SQL INSERT, UPDATE or
DELETE statement.
§ The execute() method executes an SQL statement that may return
multiple results.
The ResultSet Object
The ResultSet object provides you with methods to access data from
the table. Executing a statement usually generates a ResultSet object.
It maintains a cursor pointing to its current row of data. Initially the
cursor is positioned before the first row. The next() method moves
the cursor to the next row. You can access data from the ResultSet
rows by calling the getXXX() method where XXX is the data type.
The following code queries the database and process the ResultSet.
Using the PreparedStatement Object
18. 18
You have to develop an application that queries the database
according to the search criteria specified by a user. For example, the
user supplies the publisher ID and wants to see the details of that
publisher.
select * from publishers where pub_id=?
To make it possible, you need to prepare a query statement at
runtime with an appropriate value in the where clause.
The PreparedStatement object allows you to execute parameterized
queries. The PreparedStatement object is created using the
prepareStatement() method of the Connection object.
stat=con.prepareStatement (“select * from publishers where
pub_id=?”);
The prepareStatement(), method of the Connection object takes an
SQL statement as a parameter. The SQL statement can contain
placeholders that can be replaced by INPUT parameters at runtime.
The ‘?’ symbols is a placeholder that can be replaced by the INPUT
parameters at runtime.
Passing INPUT Parameters:
Before executing a PreparedStatement object, you must set the
value of each ‘?’ parameter. This is done by calling an appropriate
setXXX() method, where XXX is the data type of the parameter.
stat.setString(1, pid.getText());
ResultSet result=stat.executeQuery();