What is StringBuilder Class In Java ?

StringBuilder Class 

All Implemented Interfaces:

Serializable, Appendable, CharSequence

Declaration of StringBuilder:

public final class StringBuilder

extends Object

implements Serializable, CharSequence

This class belongs to java.lang; package. StringBuilder class is same as String Class, but it can be modified(means this class is mutable class). StringBuilder class is not safe in multi-threaded environment ,because StringBuilder class is not synchronized. Due to unsunchronized this class gives better performance than String and StringBuffer. 

Principle operation of StringBuilder class is append() and insert() methods, which are not available in String class, these methods are overloaded to accept any data type.

append() method add string /sequence of characters at the end of existing sequence. Whereas insert() method add the characters at the specified point.

Constructor Summary of StringBuilder:

Constructor	Description
StringBuilder()	Constructs a string builder with no characters in it and an initial capacity of 16 characters.
StringBuilder(CharSequence seq)	Constructs a string builder that contains the same characters as the specified CharSequence.
StringBuilder(int capacity)	Constructs a string builder with no characters in it and an initial capacity specified by the capacity argument.
StringBuilder(String str)	Constructs a string builder initialized to the contents of the specified string.

Example of StringBuilder:

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public class StringBuilderClassExample { public static void main(String[] args) { //StringBuilder with default Constructor StringBuilder sb = new StringBuilder(); sb.append("Java"); sb.append(" "); sb.append("Identifiers"); System.out.println(sb); //StringBuilder with String in Constructor StringBuilder sb1 = new StringBuilder("Java Is Object Oriented"); System.out.println(sb1); //StringBuilder with initial capacity in Constructor StringBuilder sb2 = new StringBuilder(20); sb2.append("I").append(" ").append("Love").append(" ").append("Java"); System.out.println(sb2); //Use of append() method - it add data at the ends StringBuilder sb3 = new StringBuilder("Java"); sb3.append("Programming"); System.out.println(sb3); //Use of insert() method - it add data at the specified point StringBuilder sb4 = new StringBuilder("Java"); sb4.insert(2, "Thread"); System.out.println(sb4); } }

Output:

Java Identifiers

Java Is Object Oriented

I Love Java

JavaProgramming

JaThreadva

      

Blog Author - Pushkar Khosla,
Software Developer by Profession with 3.0 Yrs of Experience , through this blog i'am sharing my industrial Java Knowledge to entire world. For any question or query any one can comment below or mail me at pushkar.itsitm52@gmail.com.

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