String objects are immutable in Java; a method that is passed a reference to a String object cannot change the original object.
package com.ibytecode.strings.parampassing; public class PassingStringToMethod { public static void main(String[] args) { String str = "Hello"; System.out.println("In main: Before Passing String " + "to method: " + str); method(str); System.out.println("In main: After returning " + "from method: " + str); } public static void method(String strTest) { strTest += " World"; System.out.println("In method(): " + strTest); } }
In main: Before Passing String to method: Hello
In method(): Hello World
In main: After returning from method: Hello