StringBuffer delete() Method in Java with Examples

Last Updated : 02 Feb, 2022

The java.lang.StringBuffer.delete() is an inbuilt method in Java which is used to remove or delete the characters in a substring of this sequence. The substring starts at a specified index start_point and extends to the character at the index end_point.

Syntax :

public StringBuffer delete(int start_point, int end_point)

Parameters : The method accepts two parameters of integer type:
start_point – This refers to the beginning index and is included in the count.
end_point – This refer to the ending index and is excluded from the count.

Return Value : The method returns the string after deleting the substring formed by the range mentioned in the parameters.

Exceptions : StringIndexOutOfBoundsException occurs if the start_point is negative, greater than length(), or greater than the end_point.

Examples :

Input: String = "Apple" start_point = 2 end_point = 4 Output: Ape Input: String = "GeeksforGeeks" start_point = 2 end_point = 7 Output: GerGeeks

Below programs illustrate the java.lang.StringBuffer.delete() method:
Program 1:

java

// Java program to illustrate the 
// java.lang.StringBuffer.delete() 
importjava.lang.*; 
  
publicclassgeeks { 
  
    publicstaticvoidmain(String[] args) 
    { 
  
        StringBuffer sbf = newStringBuffer("Geeksforgeeks"); 
        System.out.println("string buffer = "+ sbf); 
  
        // Deleting characters from index 2 to 7 
        sbf.delete(6, 8); 
        System.out.println("After deletion string buffer is = "+ sbf); 
    } 
} 

Output:

 string buffer = Geeksforgeeks After deletion string buffer is = Geeksfgeeks

Program 2:

java

// Java program to illustrate the 
// java.lang.StringBuffer.delete() 
importjava.lang.*; 
  
publicclassgeeks { 
  
    publicstaticvoidmain(String[] args) 
    { 
  
        StringBuffer sbf = newStringBuffer("Welcome to Geeksforgeeks"); 
        System.out.println("string buffer = "+ sbf); 
  
        // deleting characters from index 5 to index 9 
        sbf.delete(5, 9); 
        System.out.println("After deletion string buffer is = "+ sbf); 
    } 
} 

Output:

 string buffer = Welcome to Geeksforgeeks After deletion string buffer is = Welcoo Geeksforgeeks

Program 3: Here the index is negative.

java

// Java program to illustrate the 
// java.lang.StringBuffer.delete() 
importjava.lang.*; 
  
publicclassgeeks { 
  
    publicstaticvoidmain(String[] args) 
    { 
  
        StringBuffer sbf = newStringBuffer("Welcome to Geeksforgeeks"); 
        System.out.println("string buffer = "+ sbf); 
  
        sbf.delete(-5, 9); 
        System.out.println("After deletion string buffer is = "+ sbf); 
    } 
} 

Output:

 Exception in thread "main" java.lang.StringIndexOutOfBoundsException: String index out of range: -5 at java.lang.AbstractStringBuilder.delete(AbstractStringBuilder.java:756) at java.lang.StringBuffer.delete(StringBuffer.java:430) at geeks.main(geeks.java:13)

Program 4: Here the index is not present.

java

// Java program to illustrate the 
// java.lang.StringBuffer.delete() 
importjava.lang.*; 
  
publicclassgeeks { 
  
    publicstaticvoidmain(String[] args) 
    { 
  
        StringBuffer sbf = newStringBuffer("Welcome to Geeksforgeeks"); 
        System.out.println("string buffer = "+ sbf); 
  
        sbf.delete(99, 109); 
        System.out.println("After deletion string buffer is = "+ sbf); 
    } 
} 

Output:

 Exception in thread "main" java.lang.StringIndexOutOfBoundsException at java.lang.AbstractStringBuilder.delete(AbstractStringBuilder.java:760) at java.lang.StringBuffer.delete(StringBuffer.java:430) at geeks.main(geeks.java:13)

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