Generics in Java

Create a generic Class Demo:

 class Demo <T>
{
void method(T obj)    //method can take any type of data type by default it is object.
{}
}

public static void main (String [] arg)
{
Demo demo = new Demo();    //T is a object.
demo.method("string");
demo.method(10);
}

Demo <String> demo1 = new Demo<String>();
Demo <Integer> demo2 = new Demo<Integer>();
Generics works only with objects, so we cannot use for primitive data types.
Demo <int> obj3 = new Demo<int>(); // Its illegal

One generic type is not compatible with another version of the same generic type.
demo1 = demo2 //will give error because both have different type compatible.

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