Java StringBuilder capacity() method

capacity(): returns the current capacity of the string builder. Capacity refers to the amount of available storage.

Syntax:

public int capacity()

StringBuilder capacity() Example

class TestStringBuilder{
    StringBuilder sb = new StringBuilder();
    
    public void capacityTest(){
        //default capacity.
        System.out.println(sb.capacity());
        
        sb.append("Hello ");
        //current capacity 16.
        System.out.println(sb.capacity());
        
        sb.append("www.hello.com");
        //current capacity (16*2)+2=34 i.e (oldcapacity*2)+2.  
        System.out.println(sb.capacity());
    }
}

public class StringBuilderCapacityExample {
    public static void main(String args[]){
        //creating TestStringBuilder object
        TestStringBuilder obj = new TestStringBuilder();
        
        //method call
        obj.capacityTest();
    }
}

Output

16
16 
34