Java StringBuilder trimToSize() method example

public void trimToSize()

The trimToSize() method returns void.

Requires Java 1.5 and up

Below is a java code demonstrates the use of trimToSize() method of StringBuilder class. The example presented might be simple however it shows the behavior of the trimToSize() method.

package com.javatutorialhq.java.examples;

/*
 * A java example source code to demonstrate
 * the use of trimToSize() method of StringBuilder class
 */

public class StringBuilderTrimToSizeExample {

	public static void main(String[] args) {

		// initialize the StringBuilder object
		StringBuilder sb = new StringBuilder("java tutorial");
		System.out.println("Length of buffer:" + sb.length());
		System.out.println("Capacity:" + sb.capacity());
		System.out.println("Contents of buffer:" + sb);

		// try to reduce the size of the buffer
		sb.trimToSize();
		System.out.println("Length after trimming:" + sb.length());
		System.out.println("Capacity after trimming:" + sb.capacity());
		System.out.println("Contents after trimming:" + sb.toString());
	}
}

The java example source code above, demonstrates the use of trimToSize() method of StringBuilder class. Initially wecode assign a string “java tutorial” as initial contents of the StringBuilder. The length of the string is 13 as can be found using length() method. With the initial capacity of the buffer to be 16, the capacity is now 29. However we called the trimToSize() method to reduce the capacity of the buffer. Due to that, the capacity becomes the length of the string inside the buffer.

Below is the sample output when you run the above example.

• Java StringBuilder Class Tutorial
• Java Tutorial

• Oracle Java Documentation