9.Q.What is String Interning in Java?

In Java, String Interning is a memory optimization technique which ensures all distinct string values share a single copy in a specific memory region called the String Constant Pool. The intern() method is used for interning in Java.

When str.intern() method is called , the JVM performs the following tasks :

1. It checks if an identical string already exists in the String Constant Pool.
2. If the String is already exists in the String Constant Pool , it returns the reference to that existing String pool
3. If the String is not present in the String Constant pool, it adds the String to the String Constant Pool and returns its reference.

Example :

String s1=”Gift”;

String s2=”Gift”;

String s3=new String(“Gift”);

String s4=s3.intern();

System.out.println(s1==s2);//true

System.out.println(s1==s3); //false

System.out.println(s1==s4); //true as both point to the same pool address