This document provides an overview of threads in Java. It discusses what threads are, the different states threads can be in, how to set thread priorities, and the Thread class. It also covers the two main ways to create Java threads: by extending the Thread class or implementing the Runnable interface. Additional topics covered include thread groups, synchronization to avoid race conditions, and inter-thread communication.
The document discusses multithreading concepts like concurrency and threading, how to create and control threads including setting priorities and states, and how to safely share resources between threads using synchronization, locks, and wait/notify methods to avoid issues like deadlocks. It also covers deprecated thread methods and increased threading support in JDK 1.5.
The document discusses various looping constructs in Java including for, while, do-while loops as well as decision making statements like if, if-else, switch. It provides the syntax and examples of each. The key loops covered are for, which allows looping a specific number of times, while which checks a condition before running the loop body, and do-while which runs the body at least once. The document also discusses break and continue keywords that can be used within loops. For decision making, it explains if, if-else-if-else for multiple conditions, and switch for equality checks. Nested if statements are also covered.
The document discusses several core Java concepts including:
1) Comments in Java code can be single-line or multiline javadoc comments.
2) Classes are fundamental in Java and describe data objects and methods that can be applied to objects.
3) Variables and methods have scopes determined by curly braces and a variable is only available within its scope.
The document discusses different types of streams in Java including file, byte, character, and standard streams. File streams allow reading and writing of files and include classes like FileInputStream and FileOutputStream for bytes and FileReader and FileWriter for characters. Byte streams handle 8-bit bytes while character streams handle 16-bit Unicode. Standard streams in Java are System.in for input, System.out for standard output, and System.err for errors. Sample code is provided to write to and read from files.
Multithreading allows programs to have multiple threads that can run concurrently. Each thread defines a separate path of execution. Processes are programs that are executing, while threads exist within a process and share its resources. Creating a new thread requires fewer resources than creating a new process. There are two main ways to define a thread - by implementing the Runnable interface or by extending the Thread class.
A thread is an independent path of execution within a Java program. The Thread class in Java is used to create threads and control their behavior and execution. There are two main ways to create threads - by extending the Thread class or implementing the Runnable interface. The run() method contains the code for the thread's task and threads can be started using the start() method. Threads have different states like New, Runnable, Running, Waiting etc during their lifecycle.
This document discusses exception handling in C++ and Java. It defines what exceptions are and explains that exception handling separates error handling code from normal code to make programs more readable and robust. It covers try/catch blocks, throwing and catching exceptions, and exception hierarchies. Finally, it provides an example of implementing exception handling in a C++ program to handle divide-by-zero errors.
The document discusses threads and multithreading in Java. It defines a thread as a single sequential flow of control within a program. Multithreading allows a program to be divided into multiple subprograms that can run concurrently. Threads have various states like newborn, runnable, running, blocked, and dead. The key methods for managing threads include start(), sleep(), yield(), join(), wait(), notify(). Synchronization is needed when multiple threads access shared resources to prevent inconsistencies. Deadlocks can occur when threads wait indefinitely for each other.
The document discusses multithreading concepts like concurrency and threading, how to create and control threads including setting priorities and states, and how to safely share resources between threads using synchronization, locks, and wait/notify methods to avoid issues like deadlocks. It also covers deprecated thread methods and increased threading support in JDK 1.5.
The document discusses various looping constructs in Java including for, while, do-while loops as well as decision making statements like if, if-else, switch. It provides the syntax and examples of each. The key loops covered are for, which allows looping a specific number of times, while which checks a condition before running the loop body, and do-while which runs the body at least once. The document also discusses break and continue keywords that can be used within loops. For decision making, it explains if, if-else-if-else for multiple conditions, and switch for equality checks. Nested if statements are also covered.
The document discusses several core Java concepts including:
1) Comments in Java code can be single-line or multiline javadoc comments.
2) Classes are fundamental in Java and describe data objects and methods that can be applied to objects.
3) Variables and methods have scopes determined by curly braces and a variable is only available within its scope.
The document discusses different types of streams in Java including file, byte, character, and standard streams. File streams allow reading and writing of files and include classes like FileInputStream and FileOutputStream for bytes and FileReader and FileWriter for characters. Byte streams handle 8-bit bytes while character streams handle 16-bit Unicode. Standard streams in Java are System.in for input, System.out for standard output, and System.err for errors. Sample code is provided to write to and read from files.
Multithreading allows programs to have multiple threads that can run concurrently. Each thread defines a separate path of execution. Processes are programs that are executing, while threads exist within a process and share its resources. Creating a new thread requires fewer resources than creating a new process. There are two main ways to define a thread - by implementing the Runnable interface or by extending the Thread class.
A thread is an independent path of execution within a Java program. The Thread class in Java is used to create threads and control their behavior and execution. There are two main ways to create threads - by extending the Thread class or implementing the Runnable interface. The run() method contains the code for the thread's task and threads can be started using the start() method. Threads have different states like New, Runnable, Running, Waiting etc during their lifecycle.
This document discusses exception handling in C++ and Java. It defines what exceptions are and explains that exception handling separates error handling code from normal code to make programs more readable and robust. It covers try/catch blocks, throwing and catching exceptions, and exception hierarchies. Finally, it provides an example of implementing exception handling in a C++ program to handle divide-by-zero errors.
The document discusses threads and multithreading in Java. It defines a thread as a single sequential flow of control within a program. Multithreading allows a program to be divided into multiple subprograms that can run concurrently. Threads have various states like newborn, runnable, running, blocked, and dead. The key methods for managing threads include start(), sleep(), yield(), join(), wait(), notify(). Synchronization is needed when multiple threads access shared resources to prevent inconsistencies. Deadlocks can occur when threads wait indefinitely for each other.
Java abstract class & abstract methods,Abstract class in java
Abstract classes are classes that contain one or more abstract methods. An abstract method is a method that is declared, but contains no implementation. Abstract classes may not be instantiated, and require subclasses to provide implementations for the abstract methods.
This document provides an overview of serialization in Java. Serialization allows an object to be written to a stream and reconstructed from that stream later. When an object is serialized, its field values are written to preserve the object's state. The transient keyword can exclude fields from serialization. Serialization uses ObjectOutputStream to write objects and ObjectInputStream to read them back. Unique identifiers prevent version conflicts during deserialization. Classes can implement Externalizable for full control over serialization.
Serialization & De-serialization in JavaInnovationM
When you create a class, you may create an object for that particular class and once we execute/terminate the program, the object is destroyed by itself (Garbage Collector thread).
This document provides an overview of exception handling in Java. It defines what exceptions are, their purpose, and key concepts like try, catch, throw and finally blocks. It also lists some common built-in exceptions in Java like NullPointerException and ArrayIndexOutOfBoundsException. The document explains exception control flow, nested exceptions, the exception class hierarchy with Exception and Error as subclasses of Throwable, and the differences between checked and unchecked exceptions. Contact information is provided to learn more about Java and related technologies.
This document discusses decision making and control statements in Java, specifically the if-else statement. It provides examples of how if-else statements can be used to implement logic that makes decisions based on conditions, such as checking if a variable equals a value and performing different actions depending on whether the condition is true or false. Real-world examples are given, such as deciding to make pasta or sandwiches depending on whether friends are coming over. The syntax of if-else statements is also demonstrated.
- Java threads allow for multithreaded and parallel execution where different parts of a program can run simultaneously.
- There are two main ways to create a Java thread: extending the Thread class or implementing the Runnable interface.
- To start a thread, its start() method must be called rather than run(). Calling run() results in serial execution rather than parallel execution of threads.
- Synchronized methods use intrinsic locks on objects to allow only one thread to execute synchronized code at a time, preventing race conditions when accessing shared resources.
Threads allow multiple tasks to run concurrently within a single Java program. A thread represents a separate path of execution and threads can be used to improve performance. There are two main ways to create threads: by extending the Thread class or implementing the Runnable interface. Threads transition between different states like new, runnable, running, blocked, and terminated. Synchronization is needed to prevent race conditions when multiple threads access shared resources simultaneously. Deadlocks can occur when threads wait for each other in a circular manner.
This document provides an overview of Java threading concepts including the base threading topics of thread creation methods, life cycle, priorities, and synchronization. It also covers more advanced topics such as volatile variables, race conditions, deadlocks, starvation/livelock, inter-thread communication using wait/notify, thread pools, and remote method invocation. The document includes examples and explanations of key threading mechanisms in Java like semaphores and message passing.
Packages in Java are used to organize classes and provide namespace management to avoid naming conflicts. A package groups related types like classes, interfaces, enums and annotations. Programmers can define their own packages to organize related classes. Packages create a new namespace to avoid conflicts and make classes easier to locate and access. The package name is specified in a source file using the package keyword and files for a package must be stored in a subdirectory matching the package name. Classes in other packages can be accessed using their fully qualified names or by importing the package.
This document provides an introduction to the Java programming language. It discusses Java's evolution and history from 1991 to present. It also covers Java fundamentals including data types, operators, decision making and looping constructs, classes and objects, arrays and strings. The document is intended as an overview of the major topics and features in Java.
This document discusses multithreading in Java. It defines a thread as the smallest unit of processing and explains that multithreading allows executing multiple threads simultaneously by sharing memory. It provides examples of creating threads by extending the Thread class and implementing the Runnable interface. It also describes synchronization, inter-thread communication using wait(), notify(), notifyAll() methods, and the join() method.
This document provides information on processes, threads, concurrency, and parallelism in Java. It discusses that processes have separate memory spaces while threads within the same process share memory. It describes how to create threads by extending Thread or implementing Runnable. It also covers thread states, scheduling, priorities, and daemon threads.
1. The document discusses threads and multithreading in Java. It defines threads as independent paths of execution within a process and explains how Java supports multithreading.
2. Key concepts covered include the different states a thread can be in (new, ready, running, blocked, dead), thread priorities, synchronization to allow threads to safely access shared resources, and methods to control threads like start(), sleep(), join(), etc.
3. Examples are provided to demonstrate how to create and manage multiple threads that run concurrently and synchronize access to shared resources.
The document discusses String handling in Java. It describes how Strings are implemented as objects in Java rather than character arrays. It also summarizes various methods available in the String and StringBuffer classes for string concatenation, character extraction, comparison, modification, and value conversion. These methods allow extracting characters, comparing strings, modifying strings, and converting between string and other data types.
This document provides an introduction to exception handling in programming. It discusses that exceptions are unusual runtime conditions, like division by zero, that a program may encounter during execution. It explains that code that could cause exceptions is placed in a try block. When an exception occurs in the try block, it is thrown using a throw statement. The catch block then handles the exception by generating user-friendly error messages. The document provides the syntax for try, throw, and catch blocks and includes an example program that catches a division by zero exception.
Polymorphism in Java allows an object to take on multiple forms. There are two types of polymorphism: compile-time polymorphism (method overloading) and runtime polymorphism (method overriding). Method overloading involves methods with the same name but different parameters, while method overriding involves subclasses providing their own implementation of a superclass method. Runtime polymorphism determines which version of a method to call based on the object's actual type at runtime. Abstraction in Java allows hiding implementation details and showing only essential functionality through the use of abstract classes and methods.
This document provides information about applets including:
- Applets are small programs that can be embedded in web pages and run within web browsers. They allow for dynamic and interactive content.
- There are two types of applets: local applets stored on the local system and remote applets stored on remote servers.
- The lifecycle of a Java applet involves init(), start(), stop(), destroy(), and paint() methods being called in a specific order when the applet loads and runs in the browser.
itft-Decision making and branching in javaAtul Sehdev
Decision Making Statements,The if Statement, SIMPLE IF STATEMENT, The If…else Statement, Nesting of IF..Else Statements, THE else if ladder, The Switch Statement, rules apply to a switch statement
The program accepts 5 items from the command line and stores them in a Vector. It then demonstrates deleting an item, adding an item at a specified position, adding an item at the end, and printing the Vector contents. The Vector implements a dynamic array that can hold any type of objects and any number of elements. It is contained in the java.util package and is synchronized.
This document provides an introduction and overview of Java applet programming. It discusses what Java and applets are, the applet skeleton structure including common lifecycle methods like init(), start(), paint(), stop(), and destroy(). It also outlines the steps to write an applet code, compile it, and include it in an HTML file using applet tags to display the applet. An example Java applet class and HTML code is provided at the end to demonstrate a simple "Hello World" style applet.
This document discusses Java threads and related concepts like thread states, priorities, synchronization, and inter-thread communication. It covers the two main ways to create threads in Java - by extending the Thread class or implementing the Runnable interface. Synchronization techniques like using synchronized methods and blocks are presented to prevent race conditions when multiple threads access shared resources. Finally, inter-thread communication methods like wait() and notify() from the Object class are introduced.
1. The document discusses creating threads using the Runnable interface in Java.
2. The Runnable interface contains only the run() method, which is implemented by classes that want instances to run as threads.
3. To create a thread using Runnable, a Thread object is instantiated and passed the Runnable target, or the Thread object can be instantiated within the Runnable class's constructor.
Java abstract class & abstract methods,Abstract class in java
Abstract classes are classes that contain one or more abstract methods. An abstract method is a method that is declared, but contains no implementation. Abstract classes may not be instantiated, and require subclasses to provide implementations for the abstract methods.
This document provides an overview of serialization in Java. Serialization allows an object to be written to a stream and reconstructed from that stream later. When an object is serialized, its field values are written to preserve the object's state. The transient keyword can exclude fields from serialization. Serialization uses ObjectOutputStream to write objects and ObjectInputStream to read them back. Unique identifiers prevent version conflicts during deserialization. Classes can implement Externalizable for full control over serialization.
Serialization & De-serialization in JavaInnovationM
When you create a class, you may create an object for that particular class and once we execute/terminate the program, the object is destroyed by itself (Garbage Collector thread).
This document provides an overview of exception handling in Java. It defines what exceptions are, their purpose, and key concepts like try, catch, throw and finally blocks. It also lists some common built-in exceptions in Java like NullPointerException and ArrayIndexOutOfBoundsException. The document explains exception control flow, nested exceptions, the exception class hierarchy with Exception and Error as subclasses of Throwable, and the differences between checked and unchecked exceptions. Contact information is provided to learn more about Java and related technologies.
This document discusses decision making and control statements in Java, specifically the if-else statement. It provides examples of how if-else statements can be used to implement logic that makes decisions based on conditions, such as checking if a variable equals a value and performing different actions depending on whether the condition is true or false. Real-world examples are given, such as deciding to make pasta or sandwiches depending on whether friends are coming over. The syntax of if-else statements is also demonstrated.
- Java threads allow for multithreaded and parallel execution where different parts of a program can run simultaneously.
- There are two main ways to create a Java thread: extending the Thread class or implementing the Runnable interface.
- To start a thread, its start() method must be called rather than run(). Calling run() results in serial execution rather than parallel execution of threads.
- Synchronized methods use intrinsic locks on objects to allow only one thread to execute synchronized code at a time, preventing race conditions when accessing shared resources.
Threads allow multiple tasks to run concurrently within a single Java program. A thread represents a separate path of execution and threads can be used to improve performance. There are two main ways to create threads: by extending the Thread class or implementing the Runnable interface. Threads transition between different states like new, runnable, running, blocked, and terminated. Synchronization is needed to prevent race conditions when multiple threads access shared resources simultaneously. Deadlocks can occur when threads wait for each other in a circular manner.
This document provides an overview of Java threading concepts including the base threading topics of thread creation methods, life cycle, priorities, and synchronization. It also covers more advanced topics such as volatile variables, race conditions, deadlocks, starvation/livelock, inter-thread communication using wait/notify, thread pools, and remote method invocation. The document includes examples and explanations of key threading mechanisms in Java like semaphores and message passing.
Packages in Java are used to organize classes and provide namespace management to avoid naming conflicts. A package groups related types like classes, interfaces, enums and annotations. Programmers can define their own packages to organize related classes. Packages create a new namespace to avoid conflicts and make classes easier to locate and access. The package name is specified in a source file using the package keyword and files for a package must be stored in a subdirectory matching the package name. Classes in other packages can be accessed using their fully qualified names or by importing the package.
This document provides an introduction to the Java programming language. It discusses Java's evolution and history from 1991 to present. It also covers Java fundamentals including data types, operators, decision making and looping constructs, classes and objects, arrays and strings. The document is intended as an overview of the major topics and features in Java.
This document discusses multithreading in Java. It defines a thread as the smallest unit of processing and explains that multithreading allows executing multiple threads simultaneously by sharing memory. It provides examples of creating threads by extending the Thread class and implementing the Runnable interface. It also describes synchronization, inter-thread communication using wait(), notify(), notifyAll() methods, and the join() method.
This document provides information on processes, threads, concurrency, and parallelism in Java. It discusses that processes have separate memory spaces while threads within the same process share memory. It describes how to create threads by extending Thread or implementing Runnable. It also covers thread states, scheduling, priorities, and daemon threads.
1. The document discusses threads and multithreading in Java. It defines threads as independent paths of execution within a process and explains how Java supports multithreading.
2. Key concepts covered include the different states a thread can be in (new, ready, running, blocked, dead), thread priorities, synchronization to allow threads to safely access shared resources, and methods to control threads like start(), sleep(), join(), etc.
3. Examples are provided to demonstrate how to create and manage multiple threads that run concurrently and synchronize access to shared resources.
The document discusses String handling in Java. It describes how Strings are implemented as objects in Java rather than character arrays. It also summarizes various methods available in the String and StringBuffer classes for string concatenation, character extraction, comparison, modification, and value conversion. These methods allow extracting characters, comparing strings, modifying strings, and converting between string and other data types.
This document provides an introduction to exception handling in programming. It discusses that exceptions are unusual runtime conditions, like division by zero, that a program may encounter during execution. It explains that code that could cause exceptions is placed in a try block. When an exception occurs in the try block, it is thrown using a throw statement. The catch block then handles the exception by generating user-friendly error messages. The document provides the syntax for try, throw, and catch blocks and includes an example program that catches a division by zero exception.
Polymorphism in Java allows an object to take on multiple forms. There are two types of polymorphism: compile-time polymorphism (method overloading) and runtime polymorphism (method overriding). Method overloading involves methods with the same name but different parameters, while method overriding involves subclasses providing their own implementation of a superclass method. Runtime polymorphism determines which version of a method to call based on the object's actual type at runtime. Abstraction in Java allows hiding implementation details and showing only essential functionality through the use of abstract classes and methods.
This document provides information about applets including:
- Applets are small programs that can be embedded in web pages and run within web browsers. They allow for dynamic and interactive content.
- There are two types of applets: local applets stored on the local system and remote applets stored on remote servers.
- The lifecycle of a Java applet involves init(), start(), stop(), destroy(), and paint() methods being called in a specific order when the applet loads and runs in the browser.
itft-Decision making and branching in javaAtul Sehdev
Decision Making Statements,The if Statement, SIMPLE IF STATEMENT, The If…else Statement, Nesting of IF..Else Statements, THE else if ladder, The Switch Statement, rules apply to a switch statement
The program accepts 5 items from the command line and stores them in a Vector. It then demonstrates deleting an item, adding an item at a specified position, adding an item at the end, and printing the Vector contents. The Vector implements a dynamic array that can hold any type of objects and any number of elements. It is contained in the java.util package and is synchronized.
This document provides an introduction and overview of Java applet programming. It discusses what Java and applets are, the applet skeleton structure including common lifecycle methods like init(), start(), paint(), stop(), and destroy(). It also outlines the steps to write an applet code, compile it, and include it in an HTML file using applet tags to display the applet. An example Java applet class and HTML code is provided at the end to demonstrate a simple "Hello World" style applet.
This document discusses Java threads and related concepts like thread states, priorities, synchronization, and inter-thread communication. It covers the two main ways to create threads in Java - by extending the Thread class or implementing the Runnable interface. Synchronization techniques like using synchronized methods and blocks are presented to prevent race conditions when multiple threads access shared resources. Finally, inter-thread communication methods like wait() and notify() from the Object class are introduced.
1. The document discusses creating threads using the Runnable interface in Java.
2. The Runnable interface contains only the run() method, which is implemented by classes that want instances to run as threads.
3. To create a thread using Runnable, a Thread object is instantiated and passed the Runnable target, or the Thread object can be instantiated within the Runnable class's constructor.
Session 7_MULTITHREADING in java example.pptTabassumMaktum
This document discusses multithreading in Java. It begins by introducing multitasking and how computers can appear to work on multiple tasks concurrently through fast task switching by the operating system scheduler. It then discusses how multitasking can be implemented through either process-based or thread-based approaches. The rest of the document focuses on thread-based multitasking in Java, including the Java thread model, thread life cycle states, ways to create threads by extending the Thread class or implementing Runnable, and common thread methods like start(), run(), join(), yield(), sleep(), and stop().
Session 7_MULTITHREADING in java example.pptTabassumMaktum
This document discusses multithreading in Java. It begins by introducing multitasking and how computers can appear to work on multiple tasks concurrently through fast task switching by the operating system scheduler. It then discusses how multitasking can be implemented through either process-based or thread-based approaches. The rest of the document focuses on thread-based multitasking in Java, including the Java thread model, thread life cycle states, ways to create threads by extending the Thread class or implementing Runnable, and common thread methods like start(), run(), join(), yield(), sleep(), and stop().
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- The document discusses multithreading concepts in Java like thread life cycle, creating threads, thread synchronization, and inter-thread communication.
- It explains that threads are lightweight subprocesses that share memory space for better efficiency compared to processes. Threads can run concurrently to achieve multitasking.
- The key methods for working with threads are discussed including start(), sleep(), join(), getName(), setName() and currentThread().
1) The document discusses various topics related to Java multithreading including introduction to threads, creation and life cycle of threads, stopping and blocking threads, using thread methods, thread priority, thread synchronization, and inter-thread communication.
2) It provides examples of creating threads by extending the Thread class and implementing the Runnable interface. Methods like start(), run(), sleep(), setPriority(), getPriority() are discussed.
3) Synchronization techniques like synchronized keyword and wait-notify methods are explained with examples to achieve inter-thread communication and coordination.
This document discusses multithreading in Java. It defines two types of multitasking: process-based and thread-based. Process-based multitasking allows multiple programs to run concurrently, while thread-based multitasking allows a single program to perform multiple tasks simultaneously by dividing the program into threads. The document describes how to create threads by implementing the Runnable interface or extending the Thread class, and how threads can be scheduled using priorities.
This document discusses multithreading and generic programming in Java. It covers thread concepts like thread life cycle, creating threads by extending Thread class and implementing Runnable interface. It provides examples of multithreading in applications. Generic programming concepts like generic classes and methods are also briefly introduced. The key outcomes are to develop Java applications using threads and generics.
The document discusses threads and multithreading in Java. It defines a thread as a flow of execution with a beginning, execution sequence, and end. Multithreading allows multiple threads to run simultaneously within a single program. It describes how to create threads by extending the Thread class or implementing Runnable. The document also discusses thread states, priorities, synchronization, and race conditions that can occur when multiple threads access shared data.
This document discusses Java threads and multithreading. It begins by defining multitasking as allowing multiple programs to run concurrently, while multithreading refers to multiple threads of control within a single program. It notes that threads allow maintaining responsiveness during long tasks and enabling cancellation of separable tasks. The document then covers creating and managing threads in Java by extending the Thread class or implementing Runnable, and describes thread states, priorities, and daemon threads.
- Python allows programmers to write multithreaded programs that run multiple threads concurrently for more efficient use of resources and responsiveness.
- The main benefits of multithreading over multiple processes are that threads within a process can share data and resources more easily. Threads also have less memory overhead than processes.
- There are two main modules for multithreading in Python - the older thread module and the newer threading module, which provides more powerful features and methods for managing threads.
This document provides information on multithreading, networking, and other Java concepts. It discusses how to create threads in Java by extending the Thread class or implementing Runnable, and describes methods like sleep(), wait(), notify() etc. It also covers networking topics like sockets, servers, clients and protocols. Examples of socket programming and a chatting program using sockets are included. Finally, it discusses classes like URL, URLConnection and HttpURLConnection for working with URLs.
Java Multi Threading Concept
By N.V.Raja Sekhar Reddy
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The document discusses asynchronous programming in C# and .NET. It covers several approaches for asynchronous programming including threads, tasks, and the async/await keywords. It provides examples of creating and running threads, tasks that return values, waiting for tasks to complete, and chaining multiple tasks. It also covers thread pools, foreground and background threads, thread priorities, thread safety, and using locks to synchronize access to shared resources.
- Python allows programmers to write multi-threaded programs using its threading module. This allows running multiple threads concurrently to perform asynchronous tasks or operations in parallel.
- The threading module provides Thread class which represents a thread of execution. New threads can be created by subclassing Thread and overriding its run method. start() method launches the execution of the thread.
- Synchronization between threads is important to prevent race conditions. The threading module provides Lock objects to synchronize access to shared resources.
The document discusses threads and threading in Java. It covers:
- Threads allow multitasking by running multiple threads concurrently within a program.
- Threads can be created by extending the Thread class or implementing the Runnable interface.
- Threads have different states like new, ready, running, blocked, and dead. Methods like start(), sleep(), join(), yield(), etc. change a thread's state.
- Synchronization is needed to prevent data corruption when multiple threads access shared resources concurrently.
Introduction- e - waste – definition - sources of e-waste– hazardous substances in e-waste - effects of e-waste on environment and human health- need for e-waste management– e-waste handling rules - waste minimization techniques for managing e-waste – recycling of e-waste - disposal treatment methods of e- waste – mechanism of extraction of precious metal from leaching solution-global Scenario of E-waste – E-waste in India- case studies.
Comparative analysis between traditional aquaponics and reconstructed aquapon...bijceesjournal
The aquaponic system of planting is a method that does not require soil usage. It is a method that only needs water, fish, lava rocks (a substitute for soil), and plants. Aquaponic systems are sustainable and environmentally friendly. Its use not only helps to plant in small spaces but also helps reduce artificial chemical use and minimizes excess water use, as aquaponics consumes 90% less water than soil-based gardening. The study applied a descriptive and experimental design to assess and compare conventional and reconstructed aquaponic methods for reproducing tomatoes. The researchers created an observation checklist to determine the significant factors of the study. The study aims to determine the significant difference between traditional aquaponics and reconstructed aquaponics systems propagating tomatoes in terms of height, weight, girth, and number of fruits. The reconstructed aquaponics system’s higher growth yield results in a much more nourished crop than the traditional aquaponics system. It is superior in its number of fruits, height, weight, and girth measurement. Moreover, the reconstructed aquaponics system is proven to eliminate all the hindrances present in the traditional aquaponics system, which are overcrowding of fish, algae growth, pest problems, contaminated water, and dead fish.
An improved modulation technique suitable for a three level flying capacitor ...IJECEIAES
This research paper introduces an innovative modulation technique for controlling a 3-level flying capacitor multilevel inverter (FCMLI), aiming to streamline the modulation process in contrast to conventional methods. The proposed
simplified modulation technique paves the way for more straightforward and
efficient control of multilevel inverters, enabling their widespread adoption and
integration into modern power electronic systems. Through the amalgamation of
sinusoidal pulse width modulation (SPWM) with a high-frequency square wave
pulse, this controlling technique attains energy equilibrium across the coupling
capacitor. The modulation scheme incorporates a simplified switching pattern
and a decreased count of voltage references, thereby simplifying the control
algorithm.
Software Engineering and Project Management - Introduction, Modeling Concepts...Prakhyath Rai
Introduction, Modeling Concepts and Class Modeling: What is Object orientation? What is OO development? OO Themes; Evidence for usefulness of OO development; OO modeling history. Modeling
as Design technique: Modeling, abstraction, The Three models. Class Modeling: Object and Class Concept, Link and associations concepts, Generalization and Inheritance, A sample class model, Navigation of class models, and UML diagrams
Building the Analysis Models: Requirement Analysis, Analysis Model Approaches, Data modeling Concepts, Object Oriented Analysis, Scenario-Based Modeling, Flow-Oriented Modeling, class Based Modeling, Creating a Behavioral Model.
Design and optimization of ion propulsion dronebjmsejournal
Electric propulsion technology is widely used in many kinds of vehicles in recent years, and aircrafts are no exception. Technically, UAVs are electrically propelled but tend to produce a significant amount of noise and vibrations. Ion propulsion technology for drones is a potential solution to this problem. Ion propulsion technology is proven to be feasible in the earth’s atmosphere. The study presented in this article shows the design of EHD thrusters and power supply for ion propulsion drones along with performance optimization of high-voltage power supply for endurance in earth’s atmosphere.
artificial intelligence and data science contents.pptxGauravCar
What is artificial intelligence? Artificial intelligence is the ability of a computer or computer-controlled robot to perform tasks that are commonly associated with the intellectual processes characteristic of humans, such as the ability to reason.
› ...
Artificial intelligence (AI) | Definitio
Redefining brain tumor segmentation: a cutting-edge convolutional neural netw...IJECEIAES
Medical image analysis has witnessed significant advancements with deep learning techniques. In the domain of brain tumor segmentation, the ability to
precisely delineate tumor boundaries from magnetic resonance imaging (MRI)
scans holds profound implications for diagnosis. This study presents an ensemble convolutional neural network (CNN) with transfer learning, integrating
the state-of-the-art Deeplabv3+ architecture with the ResNet18 backbone. The
model is rigorously trained and evaluated, exhibiting remarkable performance
metrics, including an impressive global accuracy of 99.286%, a high-class accuracy of 82.191%, a mean intersection over union (IoU) of 79.900%, a weighted
IoU of 98.620%, and a Boundary F1 (BF) score of 83.303%. Notably, a detailed comparative analysis with existing methods showcases the superiority of
our proposed model. These findings underscore the model’s competence in precise brain tumor localization, underscoring its potential to revolutionize medical
image analysis and enhance healthcare outcomes. This research paves the way
for future exploration and optimization of advanced CNN models in medical
imaging, emphasizing addressing false positives and resource efficiency.
Rainfall intensity duration frequency curve statistical analysis and modeling...bijceesjournal
Using data from 41 years in Patna’ India’ the study’s goal is to analyze the trends of how often it rains on a weekly, seasonal, and annual basis (1981−2020). First, utilizing the intensity-duration-frequency (IDF) curve and the relationship by statistically analyzing rainfall’ the historical rainfall data set for Patna’ India’ during a 41 year period (1981−2020), was evaluated for its quality. Changes in the hydrologic cycle as a result of increased greenhouse gas emissions are expected to induce variations in the intensity, length, and frequency of precipitation events. One strategy to lessen vulnerability is to quantify probable changes and adapt to them. Techniques such as log-normal, normal, and Gumbel are used (EV-I). Distributions were created with durations of 1, 2, 3, 6, and 24 h and return times of 2, 5, 10, 25, and 100 years. There were also mathematical correlations discovered between rainfall and recurrence interval.
Findings: Based on findings, the Gumbel approach produced the highest intensity values, whereas the other approaches produced values that were close to each other. The data indicates that 461.9 mm of rain fell during the monsoon season’s 301st week. However, it was found that the 29th week had the greatest average rainfall, 92.6 mm. With 952.6 mm on average, the monsoon season saw the highest rainfall. Calculations revealed that the yearly rainfall averaged 1171.1 mm. Using Weibull’s method, the study was subsequently expanded to examine rainfall distribution at different recurrence intervals of 2, 5, 10, and 25 years. Rainfall and recurrence interval mathematical correlations were also developed. Further regression analysis revealed that short wave irrigation, wind direction, wind speed, pressure, relative humidity, and temperature all had a substantial influence on rainfall.
Originality and value: The results of the rainfall IDF curves can provide useful information to policymakers in making appropriate decisions in managing and minimizing floods in the study area.
2. 2
Topics
● What is a thread?
● Thread states
● Thread priorities
● Thread class
● Two ways of creating Java threads
– Extending Thread class
– Implementing Runnable interface
● ThreadGroup
● Synchronization
● Inter-thread communication
● Scheduling a task via Timer and TimerTask
4. 4
Threads
● Why threads?
– Need to handle concurrent processes
● Definition
– Single sequential flow of control within a program
– For simplicity, think of threads as processes executed by
a program
– Example:
● Operating System
● HotJava web browser
6. 6
Multi-threading in Java Platform
● Every application has at least one thread — or
several, if you count "system" threads that do
things like memory management and signal
handling
● But from the application programmer's point of
view, you start with just one thread, called the main
thread. This thread has the ability to create
additional threads
8. 8
Thread States
● A thread can in one of several possible states:
1.Running
● Currently running
● In control of CPU
2.Ready to run
● Can run but not yet given the chance
3.Resumed
● Ready to run after being suspended or block
4.Suspended
● Voluntarily allowed other threads to run
5.Blocked
● Waiting for some resource or event to occur
10. 10
Thread Priorities
● Why priorities?
– Determine which thread receives CPU control and gets
to be executed first
● Definition:
– Integer value ranging from 1 to 10
– Higher the thread priority → larger chance of being
executed first
– Example:
● Two threads are ready to run
● First thread: priority of 5, already running
● Second thread = priority of 10, comes in while first thread
is running
11. 11
Thread Priorities
● Context switch
– Occurs when a thread snatches the control of CPU from
another
– When does it occur?
● Running thread voluntarily relinquishes CPU control
● Running thread is preempted by a higher priority thread
● More than one highest priority thread that is ready
to run
– Deciding which receives CPU control depends on the
operating system
– Windows 95/98/NT: Uses time-sliced round-robin
– Solaris: Executing thread should voluntarily relinquish
CPU control
19. 19
Extending Thread Class
● The subclass extends Thread class
– The subclass overrides the run() method of Thread class
● An object instance of the subclass can then be
created
● Calling the start() method of the object instance
starts the execution of the thread
– Java runtime starts the execution of the thread by
calling run() method of object instance
20. 20
Two Schemes of starting a thread
from a subclass
1.The start() method is not in the constructor of the
subclass
– The start() method needs to be explicitly invoked after
object instance of the subclass is created in order to start
the thread
2.The start() method is in the constructor of the
subclass
– Creating an object instance of the subclass will start the
thread
21. 21
Scheme 1: start() method is Not in
the constructor of subclass
1 class PrintNameThread extends Thread {
2 PrintNameThread(String name) {
3 super(name);
4 }
5 public void run() {
6 String name = getName();
7 for (int i = 0; i < 100; i++) {
8 System.out.print(name);
9 }
10 }
11 }
12 //continued
22. 22
Scheme 1: start() method needs to
be called explicitly
14 class ExtendThreadClassTest1 {
15 public static void main(String args[]) {
16 PrintNameThread pnt1 =
17 new PrintNameThread("A");
18 pnt1.start(); // Start the first thread
19 PrintNameThread pnt2 =
20 new PrintNameThread("B");
21 pnt2.start(); // Start the second thread
22
23 }
24 }
23. 23
Scheme 2: start() method is in a
constructor of the subclass
1 class PrintNameThread extends Thread {
2 PrintNameThread(String name) {
3 super(name);
4 start(); //runs the thread once instantiated
5 }
6 public void run() {
7 String name = getName();
8 for (int i = 0; i < 100; i++) {
9 System.out.print(name);
10 }
11 }
12 }
13 //continued
24. 24
Scheme 2: Just creating an object
instance starts a thread
14 class ExtendThreadClassTest2 {
15 public static void main(String args[]) {
16 PrintNameThread pnt1 =
17 new PrintNameThread("A");
18 PrintNameThread pnt2 =
19 new PrintNameThread("B");
20
21 }
22 }
25. 25
Scheme 2: Just creating an object
instance starts a thread
● Can modify main method as follows:
14 class ExtendThreadClassTest3 {
15 public static void main(String args[]) {
16 new PrintNameThread("A");
17 new PrintNameThread("B");
18 }
19 }
27. 27
Runnable Interface
● The Runnable interface should be implemented by
any class whose instances are intended to be
executed as a thread
● The class must define run() method of no
arguments
– The run() method is like main() for the new thread
● Provides the means for a class to be active while
not subclassing Thread
– A class that implements Runnable can run without
subclassing Thread by instantiating a Thread instance
and passing itself in as the target
28. 28
Two Ways of Starting a Thread For
a class that implements Runnable
1.Caller thread creates Thread object and starts it
explicitly after an object instance of the class that
implements Runnable interface is created
– The start() method of the Thread object needs to be
explicitly invoked after object instance is created
2.The Thread object is created and started within the
constructor method of the class that implements
Runnable interface
– The caller thread just needs to create object instances of
the Runnable class
29. 29
Scheme 1: Caller thread creates a
Thread object and starts it explicitly
// PrintNameRunnable implements Runnable interface
class PrintNameRunnable implements Runnable {
String name;
PrintNameRunnable(String name) {
this.name = name;
}
// Implementation of the run() defined in the
// Runnable interface.
public void run() {
for (int i = 0; i < 10; i++) {
System.out.print(name);
}
}
}
30. 30
Scheme 1: Caller thread creates a
Thread object and starts it explicitly
public class RunnableThreadTest1 {
public static void main(String args[]) {
PrintNameRunnable pnt1 = new PrintNameRunnable("A");
Thread t1 = new Thread(pnt1);
t1.start();
}
}
31. 31
Scheme 2: Thread object is created
and started within a constructor
// PrintNameRunnable implements Runnable interface
class PrintNameRunnable implements Runnable {
Thread thread;
PrintNameRunnable(String name) {
thread = new Thread(this, name);
thread.start();
}
// Implementation of the run() defined in the
// Runnable interface.
public void run() {
String name = thread.getName();
for (int i = 0; i < 10; i++) {
System.out.print(name);
}
}
}
32. 32
Scheme 2: Thread object is created
and started within a constructor
public class RunnableThreadTest2 {
public static void main(String args[]) {
// Since the constructor of the PrintNameRunnable
// object creates a Thread object and starts it,
// there is no need to do it here.
new PrintNameRunnable("A");
new PrintNameRunnable("B");
new PrintNameRunnable("C");
}
}
34. 34
Extending Thread vs. Implementing
Runnable Interface
● Choosing between these two is a matter of taste
● Implementing the Runnable interface
– May take more work since we still
● Declare a Thread object
● Call the Thread methods on this object
– Your class can still extend other class
● Extending the Thread class
– Easier to implement
– Your class can no longer extend any other class
36. 36
ThreadGroup Class
● A thread group represents a set of threads
● In addition, a thread group can also include other
thread groups
– The thread groups form a tree in which every thread
group except the initial thread group has a parent
● A thread is allowed to access information about its
own thread group, but not to access information
about its thread group's parent thread group or any
other thread groups.
37. 37
Example: ThreadGroup
1 // Start three threads
2 new SimpleThread("Jamaica").start();
3 new SimpleThread("Fiji").start();
4 new SimpleThread("Bora Bora").start();
5
6 ThreadGroup group
7 = Thread.currentThread().getThreadGroup();
8
9 Thread[] tarray = new Thread[10];
10 int actualSize = group.enumerate(tarray);
11 for (int i=0; i<actualSize;i++){
12 System.out.println("Thread " +
13 tarray[i].getName() + " in thread group "
14 + group.getName());
15 }
39. 39
Race condition & How to Solve it
● Race conditions occur when multiple,
asynchronously executing threads access the same
object (called a shared resource) returning
unexpected (wrong) results
● Example:
– Threads often need to share a common resource ie a
file, with one thread reading from the file while another
thread writes to the file
● They can be avoided by synchronizing the threads
which access the shared resource
42. 42
An Unsynchronized Example
26 class TestThread {
27 public static void main(String args[]) {
28 new PrintStringsThread("Hello ", "there.");
29 new PrintStringsThread("How are ", "you?");
30 new PrintStringsThread("Thank you ",
31 "very much!");
32 }
33 }
44. 44
Synchronization:
Locking an Object
● A thread is synchronized by becoming an owner of
the object's monitor
– Consider it as locking an object
● A thread becomes the owner of the object's monitor
in one of three ways
– Option 1: Use synchronized method
– Option 2: Use synchronized statement on a common
object
54. 54
wait() method of Object Class
● wait() method causes a thread to release the lock it
is holding on an object; allowing another thread to
run
● wait() method is defined in the Object class
● wait() can only be invoked from within synchronized
code
● it should always be wrapped in a try block as it
throws IOExceptions
● wait() can only invoked by the thread that own's the
lock on the object
55. 55
wait() method of Object Class
● When wait() is called, the thread becomes disabled for
scheduling and lies dormant until one of four things
occur:
– another thread invokes the notify() method for this object
and the scheduler arbitrarily chooses to run the thread
– another thread invokes the notifyAll() method for this
object
– another thread interrupts this thread
– the specified wait() time elapses
● When one of the above occurs, the thread becomes re-
available to the Thread scheduler and competes for a
lock on the object
● Once it regains the lock on the object, everything
resumes as if no suspension had occurred
56. 56
notify() method
● Wakes up a single thread that is waiting on this
object's monitor
– If any threads are waiting on this object, one of them is
chosen to be awakened
– The choice is arbitrary and occurs at the discretion of the
implementation
● Can only be used within synchronized code
● The awakened thread will not be able to proceed
until the current thread relinquishes the lock on this
object
59. 59
Producer-Consumer
● Imagine a scenario in which there exists two
distinct threads both operating on a single shared
data area
● One thread, the Producer inserts information into
the data area whilst the other thread, the
Consumer, removes information from that same
area
● In order for the Producer to insert information into
the data area, there must be enough space
– The Producer's sole function is to insert data into the
data-area, it is not allowed to remove any data from the
area.
60. 60
Producer-Consumer
● For the Consumer to be able to remove information
from the data area, there must be information there
in the first place
– The sole function of the Consumer is to remove data
from the data area
● The solution of the Producer-Consumer problem
lies with devising a suitable communication protocol
through which the two processes may exchange
information.
● The definition of such a protocol is the main factor
that makes the Producer-Consumer problem
interesting in terms of concurrent systems
63. 63
Unsynchronized Producer-Consumer
Example: Consumer.java
1 public class Consumer extends Thread {
2 private CubbyHole cubbyhole;
3 private int number;
4
5 public Consumer(CubbyHole c, int number) {
6 cubbyhole = c;
7 this.number = number;
8 }
9
10 public void run() {
11 int value = 0;
12 for (int i = 0; i < 10; i++) {
13 value = cubbyhole.get();
14 System.out.println("Consumer #" + this.number
15 + " got: " + value);
16 }
17 }
18 }
19
64. 64
Unsynchronized Producer-
Consumer Example: Main program
1 public class ProducerConsumerUnsynchronized {
2
3 public static void main(String[] args) {
4
5 CubbyHole c = new CubbyHole();
6
7 Producer p1 = new Producer(c, 1);
8 Consumer c1 = new Consumer(c, 1);
9
10 p1.start();
11 c1.start();
12 }
13 }
65. 65
Result of Unsynchronized
Producer-Consumer
● Results are unpredictable
– A number may be read before a number has been
produced
– Multiple numbers may be produced with only one or two
being read
71. 71
Timer Class
● Provides a facility for threads to schedule tasks for
future execution in a background thread
● Tasks may be scheduled for one-time execution, or
for repeated execution at regular intervals.
● Corresponding to each Timer object is a single
background thread that is used to execute all of the
timer's tasks, sequentially
● Timer tasks should complete quickly
– If a timer task takes excessive time to complete, it "hogs"
the timer's task execution thread. This can, in turn, delay
the execution of subsequent tasks, which may "bunch
up" and execute in rapid succession when (and if) the
offending task finally completes.
72. 72
TimerTask Class
● Abstract class with an abstract method called run()
● Concrete class must implement the run() abstract
method
73. 73
Example: Timer Class
public class TimerReminder {
Timer timer;
public TimerReminder(int seconds) {
timer = new Timer();
timer.schedule(new RemindTask(), seconds*1000);
}
class RemindTask extends TimerTask {
public void run() {
System.out.format("Time's up!%n");
timer.cancel(); //Terminate the timer thread
}
}
public static void main(String args[]) {
System.out.format("About to schedule task.%n");
new TimerReminder(5);
System.out.format("Task scheduled.%n");
}
}