Special Offer - Enroll Now and Get 2 Course at ₹25000/- Only Explore Now!

All Courses
Stringbuffer in Java

Stringbuffer in Java

April 30th, 2019

Java String Buffer

Definition for String Buffer

Java String Buffer is similar to the String value class save that String function class is immutable, whereas the Java String-Buffer class remains mutable. Later than the java String-Buffer objects value can be converted back into the String objects.

How to create String-Buffer Objects

Java String-Buffer can be defined as easily by the use of the new operator and bypassing the string value inside the String-Buffer constructor.

Syntax

StringBuffer <object> = new StringBuffer(String_value)

Example

public class Test {
public static void main(String args[]) {
StringBuffer sBuffer = new StringBuffer("HelloWorld");
sBuffer.append(" String Buffer"); System.out.println(sBuffer); } }

Out Put

HelloWorld Sting Buffer

How to Data Value insert and appending the Java String-Buffer

Below method you having using data inserting/appending a string, an empty Java String-Buffer object is created.

Syntax

StringBuffer insert(int a, b);
// inserts b in the position a
Syntax for append(): StringBuffer append (b1);
// appends b1 to the StringBuffer

Example Code insert

public class Test { public static void main(String args[])
 {
StringBuffer sb = new StringBuffer("Hellototheworld");
sb.insert(5, "Welcome");
System.out.println(sb);
 }
 }

OutPut

Hellowelcometotheworld

Example code for Append

public class Test { public static void main(String args[])
{
StringBuffer sb = new StringBuffer("Welcome");
sb.append(" String Buffer"); System.out.println(sb);
}
 }

Output

Welcome String Buffer

Deleting Creating of Java Sting-Buffer

Delete the characters starting from the position p1 to p2-1th position.

Syntax:

StringBuffer delete(int p1, int p2)

Example Code

import java.lang.*;
public class StringBufferDemo {
public static void main(String[] args) {
StringBuffer buff = new StringBuffer("Java long package");
System.out.println("buffer = " + buff);
buff.delete(4, 9);
System.out.println("After deletion = " + buff);
}
}

Output

buffer : Java long package

after deletion : Java package

How to reverse the String Value using StringBuffer

Reversing a string is as simple as using the reverse() method with the StringBuffer object.

Syntax

StringBuffer reverse()

Example Code

public class Test {
public static void main(String args[]) {
StringBuffer buffer = new StringBuffer("GangBoard");
buffer.reverse();
System.out.println(buffer);
}
}

Output

draoBgnaG

Finding the length of the string value using StringBuffer

Finding the length of the StringBuffer is simple.

Syntax:

int length()

Example Code

import java.lang.*;
public class StringBufferDemo {
public static void main(String[] args) {
StringBuffer buff = new StringBuffer("GangBoard");
System.out.println("length = " + buff.length());
buff = new StringBuffer("");
System.out.println("length = " + buff.length());
}

OutPut

length:9
length : 0

Replacing character of Java String-Buffer

Sequence of Characters can be replaced with a new set of characters using the re-place() method.

Syntax:

StringBuffer replace(int i, int j, String s)

Example Code

import java.lang.*;
public class StringBufferDemo {
public static void main(String[] args) {
StringBuffer buff = new StringBuffer("Java long Package");
System.out.println("buffer = " + buff);
// prints the stringbuffer after replacing
System.out.println("After replacing: " + buff);
}
}

Output

buffer = Java long Package
After replacing: Java Lang Package

Finding the substring using String-Buffer

Retrieves the characters starting from the position I from the StringBuffer object.

Syntax

Stringbuffer substring(int i);

Example Code

import java.lang.*;
public class StringBufferDemo {
public static void main(String[] args)
{ StringBuffer buff = new StringBuffer("GangBoard");
 System.out.println("buffer = " + buff);
 // prints substring from index 3 System.out.println("substring is = " + buff.substring(3));
/* prints substring from index 1 to 4 excluding character at 4th index */ System.out.println("substring is = " + buff.substring(1, 4)); } }
Out Put

buffer = GangBoardSubstring is = nt

substring is = esa

Indeax of a Character in Java String-Buffer

Position of a character(s) can be obtained relating indexOf() method. Returns this first occurrence from the substring of left to right.

Syntax

int indexOf(String str)

Example Code

import java.lang.*; public class StringBufferDemo {
public static void main(String[] args) {
StringBuffer buff = new StringBuffer("Program code");
System.out.println("buffer = " + buff);
System.out.println("Index of substring = " + buff.indexOf("age")); System.out.println("Index of substring = " + buff.indexOf("k")); } }

Output

buffer = Program code
Index of substring = 10
Index of substring = -1