how to use String Builder java code example

Example 1: java string builder

StringBuilder stringBuilder = new StringBuilder();

stringBuilder.append("string");

System.out.println("String = " + stringBuilder.toString());

Example 2: stringbuilder in java

Java StringBuilder class is used to create
  mutable (modifiable) string. The Java
  StringBuilder class is same as StringBuffer
  class except that it is non-synchronized.
    
StringBuilder()
    creates an empty string Builder with the initial capacity of 16.
StringBuilder(String str)
    creates a string Builder with the specified string.
StringBuilder(int length)
    creates an empty string Builder with the specified capacity as length.