Java Classes | Java Tutorial for Beginners | Java Classes and Objects | Java ...Edureka!
This Edureka 'Java Classes' tutorial will take you through in-depth details of Java classes and different key-components in Java. It is ideal for both beginners and professionals who want to learn or brush up the basics of Java. Below are the topics covered in this tutorial:
1. Classes in Java
2. Constructors
3. Structure of a Class
4. Overview of Objects
5. Working with Objects
6. Multiple classes
7. OOPS concepts: Inheritance, Encapsulation, Abstraction, Interface
Java Programming | Java Tutorial For Beginners | Java Training | EdurekaEdureka!
This Edureka Java Programming tutorial will help you in understanding the various programming fundamentals of Java in detail with examples. Below are the topics covered in this tutorial:
1) Variables
2) Data Types in Java
3) Operators in Java
4) Conditional Statements in Java
5) Loops
6) Arrays and Strings
7) Functions in Java
8) Classes and Objects in Java
Java Training | Java Tutorial for Beginners | Java Programming | Java Certifi...Edureka!
This Edureka Java Training tutorial will help you in understanding the core fundamentals of Java. It helps you to learn following topics:
1) Introduction to Java
2) Java Timeline
3) Features of Java
4) How does Java work?
5) Data Types in Java
6) Operators in Java
7) Functions in Java
8) Object Oriented Concepts in Java
In this core Java training sessions, you will learn the basics of Java programming language. Following are the topics I have included in this presentations:
1. History of Java
2. Major features of Java
3. Classes and Objects
4. Class members
5. Packages
6. Constructors
7. Abstract Classes
8. Interfaces
9. OOP Characteristics
10. Access & Non-Access Modifiers
11. Passing variables
12. String
Java Class 6 | Java Class 6 |Threads in Java| Applets | Swing GUI | JDBC | Ac...Sagar Verma
16. Threads in Java
Non-Threaded Applications
Threaded Applications
Process based multitasking Vs Thread based multitasking
Thread API in Java
Creating Threads
States of a Thread
Synchronization for threads; static and non-static synchronized methods; blocks; concept of object and class locks
Coordination between threads - wait, notify and notifyAll methods for inter-thread communication
17. Applets
What are applets?
Need for Applets
Different ways of running an applet program
Applet API hierarchy
Life Cycle of an applet
Even Handlers for applets, mouse events, click events
18. Swing GUI
Introduction to AWT
Introduction to Swing GUI
Advantages of Swing over AWT
Swing API
Swing GUI Components
Event Handlers for Swing
Sample Calculator application using Swing GUI and Swing Event handling
19. JDBC
What is JDBC; introduction
JDBC features
JDBC Drivers
Setting up a database and creating a schema
Writing JDBC code to connect to DB
CRUD Operations with JDBC
Statement types in JDBC
Types of Rowset, ResultSet in JDBC
20. Access Modifiers in Java
What are access modifiers?
Default
Protected
Private
Public
ava Introduction - What is Java? Where is Java being Used? types of Java applications, facts about Java, different editions of Java technology, what you will need to run Java and about popular Java Editors.
Java Classes | Java Tutorial for Beginners | Java Classes and Objects | Java ...Edureka!
This Edureka 'Java Classes' tutorial will take you through in-depth details of Java classes and different key-components in Java. It is ideal for both beginners and professionals who want to learn or brush up the basics of Java. Below are the topics covered in this tutorial:
1. Classes in Java
2. Constructors
3. Structure of a Class
4. Overview of Objects
5. Working with Objects
6. Multiple classes
7. OOPS concepts: Inheritance, Encapsulation, Abstraction, Interface
Java Programming | Java Tutorial For Beginners | Java Training | EdurekaEdureka!
This Edureka Java Programming tutorial will help you in understanding the various programming fundamentals of Java in detail with examples. Below are the topics covered in this tutorial:
1) Variables
2) Data Types in Java
3) Operators in Java
4) Conditional Statements in Java
5) Loops
6) Arrays and Strings
7) Functions in Java
8) Classes and Objects in Java
Java Training | Java Tutorial for Beginners | Java Programming | Java Certifi...Edureka!
This Edureka Java Training tutorial will help you in understanding the core fundamentals of Java. It helps you to learn following topics:
1) Introduction to Java
2) Java Timeline
3) Features of Java
4) How does Java work?
5) Data Types in Java
6) Operators in Java
7) Functions in Java
8) Object Oriented Concepts in Java
In this core Java training sessions, you will learn the basics of Java programming language. Following are the topics I have included in this presentations:
1. History of Java
2. Major features of Java
3. Classes and Objects
4. Class members
5. Packages
6. Constructors
7. Abstract Classes
8. Interfaces
9. OOP Characteristics
10. Access & Non-Access Modifiers
11. Passing variables
12. String
Java Class 6 | Java Class 6 |Threads in Java| Applets | Swing GUI | JDBC | Ac...Sagar Verma
16. Threads in Java
Non-Threaded Applications
Threaded Applications
Process based multitasking Vs Thread based multitasking
Thread API in Java
Creating Threads
States of a Thread
Synchronization for threads; static and non-static synchronized methods; blocks; concept of object and class locks
Coordination between threads - wait, notify and notifyAll methods for inter-thread communication
17. Applets
What are applets?
Need for Applets
Different ways of running an applet program
Applet API hierarchy
Life Cycle of an applet
Even Handlers for applets, mouse events, click events
18. Swing GUI
Introduction to AWT
Introduction to Swing GUI
Advantages of Swing over AWT
Swing API
Swing GUI Components
Event Handlers for Swing
Sample Calculator application using Swing GUI and Swing Event handling
19. JDBC
What is JDBC; introduction
JDBC features
JDBC Drivers
Setting up a database and creating a schema
Writing JDBC code to connect to DB
CRUD Operations with JDBC
Statement types in JDBC
Types of Rowset, ResultSet in JDBC
20. Access Modifiers in Java
What are access modifiers?
Default
Protected
Private
Public
ava Introduction - What is Java? Where is Java being Used? types of Java applications, facts about Java, different editions of Java technology, what you will need to run Java and about popular Java Editors.
In this core java training session, you will learn Elements of Java programming. Topics covered in this session are:
• Quick review of some important concepts from last class
• History of Java
• JDK and JRE
• Byte Code and JVM (Java Virtual Machine)
• Platform Independence
• Principles of Object Oriented Programming
• Writing your first Java Application
• Elements of Java programming language
• Built in Data Types
• Conditional Statements
• Loops
For more information about this course visit on this link: https://www.mindsmapped.com/courses/software-development/learn-java-fundamentals-hands-on-training-on-core-java-concepts/
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.
Core Java introduction | Basics | free course Kernel Training
http://kerneltraining.com/core-java/
Learn the basics of Java and gain practical experience that is required to begin your career in java programming. Kernel Training has designed classroom and online course to upgrade your knowledge and skills in core Java.
Course Curriculum:
Introduction to Java
JDK and practical applications
Java Basic Data Types and Operators
Programming Constructs, Classes and Methods, constructor and Finalizer
Polymorphism
Inheritance
Method overriding and abstract classes
Packages and Interfaces
Strings and Arrays
Enums
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.
What are the top 10 Java Interview Questions and Answers in 2014? Based on the most popular java questions asked in interview, we've compiled a list of the 10 most popular java interview questions in 2014.
Appearing for a java interview is not easy but if you brush up enough fundamentals, then you can easily crack the interview. The above questions are the most popular java interview questions asked by major companies so make sure to download this pdf.
This list includes java interview questions in the below categories:
top 10 java interview questions
top 10 java interview questions and answers
10 most popular interview questions
core java interview questions and answers
basic java interview questions and answers
serialization in java interview questions
core java interview questions pdf
multithreading in java interview questions
advanced java interview questions and answers
top 10 java interview questions and answers for freshers
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java interview questions and answers pdf
java interview questions and answers for freshers
java interview questions and answers for experienced
java interview questions and answers for 3 years experience
java interview questions and answers pdf download
java collections interview questions and answers
Variables declared in a Java interface is by default final. An abstract class may contain non-final variables.
Members of a Java interface are public by default. A member of an abstract class can either be private, protected or public.
An interface is absolutely abstract and cannot be instantiated. An abstract class also cannot be instantiated, but can be invoked if it contains a main method.
Review Session and Attending Java Interviews Hitesh-Java
In this core java training session, you will learn Java Review. Topics covered in this session are:
• How to prepare for a typical Java interview?
• Typical interview questions…
For more information about this course visit on this link: https://www.mindsmapped.com/courses/software-development/learn-java-fundamentals-hands-on-training-on-core-java-concepts/
This presentation educates you about objectives of python with example syntax, OOP Terminology, Creating Classes, Creating Instance Objects, Accessing Attributes and Built-In Class Attributes.
In this core java training session, you will learn Elements of Java programming. Topics covered in this session are:
• Quick review of some important concepts from last class
• History of Java
• JDK and JRE
• Byte Code and JVM (Java Virtual Machine)
• Platform Independence
• Principles of Object Oriented Programming
• Writing your first Java Application
• Elements of Java programming language
• Built in Data Types
• Conditional Statements
• Loops
For more information about this course visit on this link: https://www.mindsmapped.com/courses/software-development/learn-java-fundamentals-hands-on-training-on-core-java-concepts/
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.
Core Java introduction | Basics | free course Kernel Training
http://kerneltraining.com/core-java/
Learn the basics of Java and gain practical experience that is required to begin your career in java programming. Kernel Training has designed classroom and online course to upgrade your knowledge and skills in core Java.
Course Curriculum:
Introduction to Java
JDK and practical applications
Java Basic Data Types and Operators
Programming Constructs, Classes and Methods, constructor and Finalizer
Polymorphism
Inheritance
Method overriding and abstract classes
Packages and Interfaces
Strings and Arrays
Enums
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.
What are the top 10 Java Interview Questions and Answers in 2014? Based on the most popular java questions asked in interview, we've compiled a list of the 10 most popular java interview questions in 2014.
Appearing for a java interview is not easy but if you brush up enough fundamentals, then you can easily crack the interview. The above questions are the most popular java interview questions asked by major companies so make sure to download this pdf.
This list includes java interview questions in the below categories:
top 10 java interview questions
top 10 java interview questions and answers
10 most popular interview questions
core java interview questions and answers
basic java interview questions and answers
serialization in java interview questions
core java interview questions pdf
multithreading in java interview questions
advanced java interview questions and answers
top 10 java interview questions and answers for freshers
top 100 java interview questions and answers
java interview questions and answers pdf
java interview questions and answers for freshers
java interview questions and answers for experienced
java interview questions and answers for 3 years experience
java interview questions and answers pdf download
java collections interview questions and answers
Variables declared in a Java interface is by default final. An abstract class may contain non-final variables.
Members of a Java interface are public by default. A member of an abstract class can either be private, protected or public.
An interface is absolutely abstract and cannot be instantiated. An abstract class also cannot be instantiated, but can be invoked if it contains a main method.
Review Session and Attending Java Interviews Hitesh-Java
In this core java training session, you will learn Java Review. Topics covered in this session are:
• How to prepare for a typical Java interview?
• Typical interview questions…
For more information about this course visit on this link: https://www.mindsmapped.com/courses/software-development/learn-java-fundamentals-hands-on-training-on-core-java-concepts/
This presentation educates you about objectives of python with example syntax, OOP Terminology, Creating Classes, Creating Instance Objects, Accessing Attributes and Built-In Class Attributes.
Chapter 02: Classes Objects and Methods Java by Tushar B KuteTushar B Kute
The lecture was condcuted by Tushar B Kute at YCMOU, Nashik through VLC orgnanized by MSBTE. The contents can be found in book "Core Java Programming - A Practical Approach' by Laxmi Publications.
Enhancing Research Orchestration Capabilities at ORNL.pdfGlobus
Cross-facility research orchestration comes with ever-changing constraints regarding the availability and suitability of various compute and data resources. In short, a flexible data and processing fabric is needed to enable the dynamic redirection of data and compute tasks throughout the lifecycle of an experiment. In this talk, we illustrate how we easily leveraged Globus services to instrument the ACE research testbed at the Oak Ridge Leadership Computing Facility with flexible data and task orchestration capabilities.
Prosigns: Transforming Business with Tailored Technology SolutionsProsigns
Unlocking Business Potential: Tailored Technology Solutions by Prosigns
Discover how Prosigns, a leading technology solutions provider, partners with businesses to drive innovation and success. Our presentation showcases our comprehensive range of services, including custom software development, web and mobile app development, AI & ML solutions, blockchain integration, DevOps services, and Microsoft Dynamics 365 support.
Custom Software Development: Prosigns specializes in creating bespoke software solutions that cater to your unique business needs. Our team of experts works closely with you to understand your requirements and deliver tailor-made software that enhances efficiency and drives growth.
Web and Mobile App Development: From responsive websites to intuitive mobile applications, Prosigns develops cutting-edge solutions that engage users and deliver seamless experiences across devices.
AI & ML Solutions: Harnessing the power of Artificial Intelligence and Machine Learning, Prosigns provides smart solutions that automate processes, provide valuable insights, and drive informed decision-making.
Blockchain Integration: Prosigns offers comprehensive blockchain solutions, including development, integration, and consulting services, enabling businesses to leverage blockchain technology for enhanced security, transparency, and efficiency.
DevOps Services: Prosigns' DevOps services streamline development and operations processes, ensuring faster and more reliable software delivery through automation and continuous integration.
Microsoft Dynamics 365 Support: Prosigns provides comprehensive support and maintenance services for Microsoft Dynamics 365, ensuring your system is always up-to-date, secure, and running smoothly.
Learn how our collaborative approach and dedication to excellence help businesses achieve their goals and stay ahead in today's digital landscape. From concept to deployment, Prosigns is your trusted partner for transforming ideas into reality and unlocking the full potential of your business.
Join us on a journey of innovation and growth. Let's partner for success with Prosigns.
Globus Connect Server Deep Dive - GlobusWorld 2024Globus
We explore the Globus Connect Server (GCS) architecture and experiment with advanced configuration options and use cases. This content is targeted at system administrators who are familiar with GCS and currently operate—or are planning to operate—broader deployments at their institution.
Gamify Your Mind; The Secret Sauce to Delivering Success, Continuously Improv...Shahin Sheidaei
Games are powerful teaching tools, fostering hands-on engagement and fun. But they require careful consideration to succeed. Join me to explore factors in running and selecting games, ensuring they serve as effective teaching tools. Learn to maintain focus on learning objectives while playing, and how to measure the ROI of gaming in education. Discover strategies for pitching gaming to leadership. This session offers insights, tips, and examples for coaches, team leads, and enterprise leaders seeking to teach from simple to complex concepts.
Providing Globus Services to Users of JASMIN for Environmental Data AnalysisGlobus
JASMIN is the UK’s high-performance data analysis platform for environmental science, operated by STFC on behalf of the UK Natural Environment Research Council (NERC). In addition to its role in hosting the CEDA Archive (NERC’s long-term repository for climate, atmospheric science & Earth observation data in the UK), JASMIN provides a collaborative platform to a community of around 2,000 scientists in the UK and beyond, providing nearly 400 environmental science projects with working space, compute resources and tools to facilitate their work. High-performance data transfer into and out of JASMIN has always been a key feature, with many scientists bringing model outputs from supercomputers elsewhere in the UK, to analyse against observational or other model data in the CEDA Archive. A growing number of JASMIN users are now realising the benefits of using the Globus service to provide reliable and efficient data movement and other tasks in this and other contexts. Further use cases involve long-distance (intercontinental) transfers to and from JASMIN, and collecting results from a mobile atmospheric radar system, pushing data to JASMIN via a lightweight Globus deployment. We provide details of how Globus fits into our current infrastructure, our experience of the recent migration to GCSv5.4, and of our interest in developing use of the wider ecosystem of Globus services for the benefit of our user community.
Field Employee Tracking System| MiTrack App| Best Employee Tracking Solution|...informapgpstrackings
Keep tabs on your field staff effortlessly with Informap Technology Centre LLC. Real-time tracking, task assignment, and smart features for efficient management. Request a live demo today!
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Innovating Inference - Remote Triggering of Large Language Models on HPC Clus...Globus
Large Language Models (LLMs) are currently the center of attention in the tech world, particularly for their potential to advance research. In this presentation, we'll explore a straightforward and effective method for quickly initiating inference runs on supercomputers using the vLLM tool with Globus Compute, specifically on the Polaris system at ALCF. We'll begin by briefly discussing the popularity and applications of LLMs in various fields. Following this, we will introduce the vLLM tool, and explain how it integrates with Globus Compute to efficiently manage LLM operations on Polaris. Attendees will learn the practical aspects of setting up and remotely triggering LLMs from local machines, focusing on ease of use and efficiency. This talk is ideal for researchers and practitioners looking to leverage the power of LLMs in their work, offering a clear guide to harnessing supercomputing resources for quick and effective LLM inference.
A Comprehensive Look at Generative AI in Retail App Testing.pdfkalichargn70th171
Traditional software testing methods are being challenged in retail, where customer expectations and technological advancements continually shape the landscape. Enter generative AI—a transformative subset of artificial intelligence technologies poised to revolutionize software testing.
Developing Distributed High-performance Computing Capabilities of an Open Sci...Globus
COVID-19 had an unprecedented impact on scientific collaboration. The pandemic and its broad response from the scientific community has forged new relationships among public health practitioners, mathematical modelers, and scientific computing specialists, while revealing critical gaps in exploiting advanced computing systems to support urgent decision making. Informed by our team’s work in applying high-performance computing in support of public health decision makers during the COVID-19 pandemic, we present how Globus technologies are enabling the development of an open science platform for robust epidemic analysis, with the goal of collaborative, secure, distributed, on-demand, and fast time-to-solution analyses to support public health.
Into the Box Keynote Day 2: Unveiling amazing updates and announcements for modern CFML developers! Get ready for exciting releases and updates on Ortus tools and products. Stay tuned for cutting-edge innovations designed to boost your productivity.
In 2015, I used to write extensions for Joomla, WordPress, phpBB3, etc and I ...Juraj Vysvader
In 2015, I used to write extensions for Joomla, WordPress, phpBB3, etc and I didn't get rich from it but it did have 63K downloads (powered possible tens of thousands of websites).
AI Pilot Review: The World’s First Virtual Assistant Marketing SuiteGoogle
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✅More than 85 AI features are included in the AI pilot.
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✅You Can Use AI Pilot To Create your version of AI Pilot And Charge People For It…
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(3) AI Partner & Profit Review: https://sumonreview.com/ai-partner-profit-review
(4) AI Ebook Suite Review: https://sumonreview.com/ai-ebook-suite-review
Understanding Globus Data Transfers with NetSageGlobus
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OpenFOAM solver for Helmholtz equation, helmholtzFoam / helmholtzBubbleFoamtakuyayamamoto1800
In this slide, we show the simulation example and the way to compile this solver.
In this solver, the Helmholtz equation can be solved by helmholtzFoam. Also, the Helmholtz equation with uniformly dispersed bubbles can be simulated by helmholtzBubbleFoam.
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The European Union Agency for Law Enforcement Cooperation (Europol) has suffered an alleged data breach after a notorious threat actor claimed to have exfiltrated data from its systems. Infamous data leaker IntelBroker posted on the even more infamous BreachForums hacking forum, saying that Europol suffered a data breach this month.
The alleged breach affected Europol agencies CCSE, EC3, Europol Platform for Experts, Law Enforcement Forum, and SIRIUS. Infiltration of these entities can disrupt ongoing investigations and compromise sensitive intelligence shared among international law enforcement agencies.
However, this is neither the first nor the last activity of IntekBroker. We have compiled for you what happened in the last few days. To track such hacker activities on dark web sources like hacker forums, private Telegram channels, and other hidden platforms where cyber threats often originate, you can check SOCRadar’s Dark Web News.
Stay Informed on Threat Actors’ Activity on the Dark Web with SOCRadar!
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Venez le découvrir lors de cette session ignite
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Discover the essential features to incorporate in your Winzo clone app to boost business growth, enhance user engagement, and drive revenue. Learn how to create a compelling gaming experience that stands out in the competitive market.
Top Features to Include in Your Winzo Clone App for Business Growth (4).pptx
Java defining classes
1. Defining Classes in JAVA
Mehdi Ali Soltani
mehdi.alisoltani@gmail.com
https://www.linkedin.com/in/mehdi-ali-soltani-315453b7/
2. WHAT IS A CLASS?
A class is a prescription for a particular kind of object.
3. Class Properties
➢ Fields: These are variables that store data items that typically differentiate
one object of the class from another. They are also referred to as data
members of a class.
➢ Methods: These define the operations you can perform for the class so they
determine what you can do to, or with, objects of the class. Methods typically
operate on the fields the data members of the class.
4. Static and non Static Fields
➢ Non-static fields, also called instance variables :
Each object of the class has its own copy of each of the non-static fields or
instance variables that appear in the class definition.
➢ Static fields, also called class variables
A given class has only one copy of each of its static fields or class variables,
and these are shared between and among all the objects of the class
6. ➢ instance methods
instance methods can be executed only in relation to a particular object
MyObject obj = new MyObject();//Create an instance
obj.nonstaticMethod();//Refer to the instance's class's code
➢ class methods
Class method can be executed even when no objects of a class exist
e.g main(), Math.sqrt(), ...
Methods in a Class Definition
7. Accessing Variables and Methods
➢ static method
double rootPi = Math.sqrt(Math.PI);
➢ Non static method
double ballVolume = ball.volume();
8. Final Fields
final fields means that the field cannot be modified by the methods in the class
final double PI = 3.14;
You should provide an initial value for a final field when you declare it.
11. Returning from a Method
To return a value from a method when its execution is complete use a return
statement.
return return_value;
12. The Parameter List
Parameter and an argument:
➢ A parameter has a name and a type and appears in the parameter list in the
definition of a method. A parameter defines the type of value that can be
passed to the method when it is called.
➢ An argument is a value that is passed to a method when it is executed, and
the value of the argument is referenced by the parameter name during
execution of the method
14. How Argument Values are Passed to a Method
All argument values are transferred to a method using what is called the
pass-by-value mechanism
15. A method can change an object that is passed as an argument. This is because a
variable of a class type contains a reference to an object, not the object itself.
Thus, when you use a variable of a class type as an argument to a method, a copy
of a reference to the object is passed to the method, not a copy of the object
itself. Because a copy of a reference still refers to the same object, the
parameter name used in the body of a method refers to the original object that
was passed as the argument.
Passing Objects to Methods
16. Final Parameters
Specifying any of the parameters for a method as final. This has the effect of
preventing modification of any argument value that is substituted for the
parameter when you call the method.
18. Defining Class Methods(cont.)
Remember that you cannot directly refer to any of the instance variables in the
class within a static method. This is because a static method can be executed
when no objects of the class have been created, and therefore no instance
variables exist.
20. Variable this
Every instance method has a variable with the name this that refers to the current
object for which the method is being called. The compiler uses this implicitly
when your method refers to an instance variable of the class
return 4.0/3.0*PI* this.radius *this.radius*this.radius;
21. Sources of Data Available within a Method
➢ Arguments passed to the method, which you refer to by using the parameter
names
➢ Data members, both instance variables and class variables, which you refer
to by their names
➢ Local variables that you declare in the body of the method
➢ Values that are returned by other methods that are called from within the
method
23. CONSTRUCTORS
When you create an object of a class, a special kind of method called a
constructor is always invoked
If you don't define any constructors for your class, the compiler supplies a
default constructor in the class, which does nothing
24. Constructor Characteristics
➢ A constructor never returns a value, and you must not specify a return type
not even of type void
➢ A constructor always has the same name as the class.
27. Passing Objects to a Method
When you pass an object as an argument to a method, the mechanism that
applies is called pass-by-reference, because a copy of the reference contained in
the variable is transferred to the method, not a copy of the object itself.
29. The Lifetime of an Object
The lifetime of an object is determined by the variable that holds the reference
you can reset a variable to refer to nothing by setting its value to null.
ball = null;
the variable ball no longer refers to an object. The lifetime of an object is
determined by whether any variable anywhere in the program still references it.
The process of disposing of dead objects is called garbage collection
31. METHOD OVERLOADING
Java enables you to define several methods in a class with the same name, as
long as each method has a unique set of parameters. Defining two or more
methods with the same name in a class is called method overloading
Different ways to overload the method
1. By changing number of arguments
2. By changing the data type
35. Calling a Constructor from a Constructor
One class constructor can call another constructor in the same class in its first
executable statement.
To refer to another constructor in the same class, use this as the method name,
followed by the appropriate arguments between parentheses
37. Duplicating Objects Using a Constructor
Sphere eightBall = new Sphere(10.0, 10.0, 0.0);
Later in your program you want to create a new object newBall, which is identical
to the object eightBall.
If you write
Sphere newBall = eightBall;
variable newBall references the same object as eightBall. You don't have a
distinct object
39. UNDERSTANDING PACKAGES
package is a namespace that organizes a set of related classes and interfaces.
Conceptually you can think of packages as being similar to different folders on
your computer.
41. Adding Classes from a Package to Your Program
Import by using the import keyword:
import package.myclass;
42. CONTROLLING ACCESS TO CLASS MEMBERS
Provide you you control the accessibility of class members from outside the class.
Using Access Attributes
ATTRIBUTE PERMITTED ACCESS
No access attribute From methods in any class in the same package.
public From methods in any class anywhere as long as the
class has been declared as public.
private Accessible only from methods inside the class. No
access from outside the class at all.
protected From methods in any class in the same package
and from any subclass anywhere.
46. Choosing Access Attributes
variables in a public class should be private and the methods that are called from
outside the class should be public.
➢ For classes in a package that are not public, and therefore not accessible outside the package, it
may sometimes be convenient to allow other classes in the package direct access to the data
members.
➢ If you have data members that have been specified as final so that their values are fi xed and they
are likely to be useful outside the class, you might as well declare them to be public.
➢ You may well have methods in a class that are intended to be used only internally by other
methods in the same class. In this case you should specify these as private.
➢ In a class like the standard class Math, which is just a convenient container for utility functions
and standard data values, you should make everything public.
47. NESTED CLASSES
All the classes you have defined so far have been separate from each other —
each stored away in its own source file. You can put the definition of one class
inside the definition of another class. The inside class is called a nested class. A
nested class can itself have another class nested inside it, if need be.