Answer Posted / nilesh bhil( mca) amravati

String is immutable.
It means that we cant change the content of String once created. If we try append a new string using + operator
then it creates new String object.
ex.
string s = new String("Java");
s = s + "bean" ;// this statement creates new object.
String class does not have method that append new String to old String in object.


where as StringBuffer class is mutable. It means that we can add new String to it using append() method.
ex.
StringBuffer sb = new StringBuffer("Java");
sb.append("Bean");

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