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What does obj mean in java

May 01, 2024 pm 06:18 PM

In Java, "obj" is a variable name that refers to an object, which is an instance of a class and represents an entity in the application. To create an object, define the class, create an instance using the new keyword, and assign its reference to a variable (such as obj). The object can access properties and methods (such as obj.name = "John Doe"), and its life cycle ends from creation to when it is no longer referenced. The garbage collector will automatically release the memory of the object that is no longer referenced.

What does obj mean in java

obj in Java

In Java, "obj" is a variable name, representing an object. An object is an instance of a class that represents an actual entity in the application.

How to create an object

To create an object, you need:

  1. Define a class that describes the properties and behavior of the object.
  2. Use the new keyword to create an instance of a class. This allocates memory and creates a new object of this class.
  3. Assign an object reference to a variable, usually called obj.

For example:

class Person {
    String name;
    int age;
}

Person obj = new Person();
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In this example, obj is a reference to a newly created Person Instance of class.

Working with Objects

Once an object is created, it can be used to access its properties and methods. You can use the dot operator (.) to access object properties and call its methods.

For example:

obj.name = "John Doe";
int age = obj.getAge();
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The life cycle of an object

The life cycle of an object begins when it is created and ends when it is no longer used. until the program is referenced. The garbage collector automatically releases memory for objects that are no longer referenced.

Note:

  • "obj" is just a variable name, you can freely choose to name the variable.
  • Objects can store any type of data, including other objects.
  • The object reference itself occupies memory space, but it does not occupy the space occupied by the object itself.

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