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Java Choice Example

Java Choice Example

In Java Choice Example, The Choice class is used to create a pop-up list of items from which the user may choose. Thus, a Choice control is a form of menu. When inactive, a Choice component takes up only enough space to show the currently selected item. When the user clicks on it, the whole list of choices pops up, and a new selection can be made. Each item in the list is a…

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Java Check box Class

Java Check box Class

Java Check box Class

A Java check box class object is a control that is used to turn an option check or unchecked. User can change the state of a check box by clicking on it. Check boxes can be used individually or as part of a group. Check boxes are objects of the Checkbox class.

Checkbox supports these constructors:

Checkbox( ) throws HeadlessException

Checkbox(String str) throws…

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Java Button Class

Java Button Class

Java Button Class component is a control that has a label and generates an event when pressed. When a button is pressed and released, AWT sends an instance of ActionEvent to the button, by calling processEvent on the button. The button’s processEvent method receives all events for the button; it passes an action event along by calling its own processActionEvent method. The…

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Java Applet Parameter

Java Applet Parameter

In The Topic Java Applet Parameter, to pass parameter into applet program. We have to use <PARAM> tag of <APPLET> tag. <PARAM> tag have name option to  named parameter and value option to set the value of that parameter tag.

In Applet code there is one tag which is used to pass parameter from web-browser to Java Applet program. The parameter is fetched using…

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Java Applet Example

Java Applet Example

Java Applet Example, is created using java Applet class functionality. Java Applets are special purpose GUI programs those can be run on several ways like, using appletviewer tool or on third party web browser.

1. To run applet using “appletviewer” program

If you want to run Applet program using third-party “appletviewer” program then, you must add tag with necessary  property…

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Java AWT

Java AWT Abstract Window Toolkit – Classes

The Design of the Java AWT is an excellent example of using classes, inheritances, and interfaces. The AWT contains the following essential classes. The class’s hierarchical relationship is shown below.

Component: This is a super class of all AWT user interface classes.

Container:This is used to group components. A container can be embedded in another…

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Java Applet

Java Applet

The Java Applets are small Java programs that are primarily used in Internet computing. They can be transported over the Internet from one computer to another and run using the Applet Viewer  or any Web Browser that supports Java. An Applet, like any application program, can do many things for us. It can perform arithmetic operations, display graphics, play sounds, accepts user input,…

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Java Thread Example

Java Thread Example

In Java Thread Example, Creating threads in Java is simple. Threads are implemented in the form of objects that contain a method called run(). The run() method is the heart and soul of any thread. It makes up the entire body of the thread and is the only method in which the thread’s behavior can be implemented.

public void run()

{

…………

……….. (statements for implementing thread)

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Java Thread Life Cycle

Java Thread Life Cycle

Java Thread Life Cycle

During the java thread life cycle, there are many states it can enter. They include:

Newborn State

Runnable State

Running State

Blocked State

Dead State

A thread is always in one of these five states. It can move from one state to another via a variety of ways. Shown in below figure.

                             Java Thread Life Cycle

1.      Newborn State :

When we create…

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Java Multithreading

Java Multithreading

Java Multithreading is a conceptual programming paradigm where a program (process) is divided into two or more subprograms (processes), which can be implemented at the same time in parallel. For example, one subprogram can display an animation on the screen while another may build the next animation to be displayed. This is something similar to dividing a task into subtasks…

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Java Exception Handling

Java Exception Handling

In Java Exception Handling, When Runtime Error occurred in program can be terminated abnormally and cannot display output or proper error message.

So, at runtime if program can be terminated without inform any error that can be understand by programmer, it is very crucial to find an error in program or taken output.

If programmer can be expected that error in his code, it…

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Java Exception

Java Exception

An exception is a condition that is caused by a run-time error in the program. When the Java interpreter encounter an error such as dividing an integer by zero, it creates an exception object and throws it (i.e., informs us that an error has occurred).

If the exception object is not caught and handled properly, the interpreter will display an error message and will terminate the…

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Java Wrapper Classes

Java Wrapper Classes

In Java Wrapper Classes, The vectors cannot handle primitive data types like int, float, long, char,  and double. Primitive data types may be converted into object types by using the wrapper classes contained in the java.lang package. Below table shows the simple data types and their corresponding wrapper class types.

Simple Type Wrapper Classboolean Boolean char…

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Java Vector class

Java Vector class

The Java Vector class contained in the java.util package. This class can be used to create a generic dynamic array known as vector that can hold objects of any type and any number. The objects do not have to be homogenous. Arrays can be easily implemented as vectors. Vectors are created like arrays as follows:

  Vector intVect = new Vector(); //declaring without size

Vector list…

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Java Static Members

Java Static Members

In Java Static Members, A class basically contains two sections. One declares variables and the other declares methods. These variables and methods are called instance variables and instance methods. This is because every time the class is instantiated, a new copy of each of them is created. They are accessed using the objects (with dot operator).

Let us assume that we want to…

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Java Method Overloading

Java Method Overloading

In Java Method Overloading, It is possible to create methods that have the same name, but different parameter lists and different definitions. This is called Method Overloading. Method overloading is used when objects are required to perform similar tasks but using different input parameters. When we call a method in an object, Java matches up the method name first and then…

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Class and Object Example

Class and Object Example

Class and Object Example

in Class and Object Example, A class is a user-defined data type with a templates that serves to define its properties. Once the class type has been defined, we can create “variables” of that type using declarations that are similar to the basic type declarations. In java, these variables are termed as instances of classes, which are the actual objects. The basic form of…

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