how to replace char in string java code example

Example 1: string replace java

public static void main(String args[]){  
String s1="my name is khan my name is java";  
String replaceString=s1.replace("is","was");//replaces all occurrences of "is" to "was"  
System.out.println(replaceString);  
}}

Example 2: java replace character in string

String s = "new String";
String replaced = s.replace("new","Test");
							  ^		 ^
                             old    new char

Example 3: replace character in string java

String str = ".............................."; 

        int index = 5; 
  
        char ch = '|'; 
 
        StringBuilder string = new StringBuilder(str); 
        string.setCharAt(index, ch); 

        System.out.println(string);