java generics array code example

Example 1: java generic array

public <T> T[] getArray(int size) {
    T[] genericArray = (T[]) new Object[size];
    return genericArray;
}

Example 2: generics Interface in java

/*We know that Java inheritance allows us to assign a variable A to another variable B if A is subclass of B. So we might think that any generic type of A can be assigned to generic type of B, but it’s not the case. Let’s see this with a simple program.

We are not allowed to assign MyClass<String> variable to MyClass<Object> variable because they are not related, in fact MyClass<T> parent is Object.*/
package com.journaldev.generics;

public class GenericsInheritance {

	public static void main(String[] args) {
		String str = "abc";
		Object obj = new Object();
		obj=str; // works because String is-a Object, inheritance in java
		
		MyClass<String> myClass1 = new MyClass<String>();
		MyClass<Object> myClass2 = new MyClass<Object>();
		//myClass2=myClass1; // compilation error since MyClass<String> is not a MyClass<Object>
		obj = myClass1; // MyClass<T> parent is Object
	}
	
	public static class MyClass<T>{}

}