How to replace string with another string in java using String.replace() method?

Consider the program:

Here, we have two strings str1 and str2, str2 will be replaced with str1 and finally, str1 is the replaced string (which will be returned through the function).

//Java Program to replace a string with new one.

public class JavaStringReplacePrg
{
	public static void main(String args[])
	{
		//string 1
		String str1="www.includehelp.com";
		//string 2
		String str2="Hello World!";

		//printing strings before replacing
		System.out.println("\nStrings before replacing:");
		System.out.println("str1: "+str1 +"\nstr2:" + str2);
		
		//replacing string str1 with str2
		str1=str1.replace(str1, str2);

		//printing strings after replacing
		System.out.println("\nStrings after replacing:");
		System.out.println("str1: "+str1 +"\nstr2:" + str2);
	}
}

Output

Strings before replacing:
str1: www.includehelp.com
str2:Hello World!

Strings after replacing:
str1: Hello World!
str2:Hello World!