How to Convert string to StringBuilder and vise versa in Java

• We can Covert String to string builder in two ways

1. Using constructor of StringBuilder(String s)
2. Using append method of StringBuilder 

• Lets see a java program to convert java String object to StringBuilder using constructor of StringBuilder class.

#1: Java program to convert string to StringBuilder using constructor of StringBuilder class.

1. package com.instanceofjava;
2. /**
3.  * @author www.Instanceofjava.com
4.  * @category interview programs
5.  * 
6.  * Description: Java Program to convert String to StringBuilder
7.  *
8.  */
9. public class StringBuilderDemo {
10. 
    
11. public static void main(String[] args) {
13. String str="java";
14. StringBuilder sb = new StringBuilder(str);
15. String s = sb.toString();
16. System.out.println(s);
18. StringBuilder stebldr= new StringBuilder("convert string to stringbuilder");
19. String st = stebldr.toString();
20. System.out.println(st);
21. }
22. 
    
23. }
24. 
    

Output

1. java
2. convert string to stringbuilder

#2: Java program to convert string to StringBuilder using append method of StringBuilder class.

1. package com.instanceofjava;
2. /**
3.  * @author www.Instanceofjava.com
4.  * @category interview programs
5.  * 
6.  * Description: Java Program to convert String to StringBuilder
7.  *
8.  */
9. public class StringBuilderDemo {
10. 
    
11. public static void main(String[] args) {
12. 
    
13. StringBuilder sb = new StringBuilder();
15. sb.append("Java convert string to StringBuilder ");
16. System.out.println(sb);
18. String str= "Convert string to Stringbuilder" ;
19. sb.append(str);
20. System.out.println(sb);
22. }
23. 
    
24. }

Output

1. Java convert string to StringBuilder 
2. Java convert string to StringBuilder Convert string to Stringbuilder

• We can Convert StringBuilder to String by using toString() method of StringBuilder class.
• How to convert StringBuilder to String in java.

#3: Java program to convert string to StringBuilder using append method of StringBuilder class.

1. package com.instanceofjava;
2. /**
3.  * @author www.Instanceofjava.com
4.  * @category interview programs
5.  * 
6.  * Description: Java Program to convert StringBuilder to String
7.  *
8.  */
9. public class StringBuilderDemo {
10. 
    
11. public static void main(String[] args) {
12. 
    
13. StringBuilder sb = new StringBuilder();
15. sb.append("Java convert  StringBuilder to string");
16. String str=sb.toString();
17. System.out.println(str);
19. String s= "Convert Stringbuilder to string " ;
20. sb.append(s);
21. String st=sb.toString();
22. System.out.println(st);
24. }
25. 
    
26. }

Output

1. Java convert  StringBuilder to string
2. Java convert  StringBuilder to stringConvert Stringbuilder to string