StringBuilder length and capacity

In this chapter you will learn:

How to get the length for a StringBuilder
How to get the capacity for a StringBuilder

Get the length

int length() returns the length (character count).

public class Main {
  public static void main(String[] argv) {
    StringBuilder sb = new StringBuilder();
    sb.append("java2s.com");
//from  ja v  a2s .  c  om
    System.out.println(sb.length());
    System.out.println(sb.capacity());

    
    sb.trimToSize();
    
    System.out.println(sb.length());
    System.out.println(sb.capacity());
    
  }
}

The output:

Get the capacity

int capacity() returns the current capacity.

public class Main {
  public static void main(String[] a) {
    StringBuilder builder1 = new StringBuilder();
    StringBuilder builder2 = new StringBuilder(0);
    StringBuilder builder3 = new StringBuilder(100);
/*from  ja v  a2  s. c  om*/
    System.out.println(builder1.capacity());
    System.out.println(builder2.capacity());
    System.out.println(builder3.capacity());

  }

}