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Java Tutorial : Java StringBuilder Introduction

Java Tutorial : Java StringBuilder Introduction

Java Tutorial : Java StringBuilder Introduction

public class StringBuilderDemo
{

    public static void main(String[] args)
    {
        /*
         * Constructs a string Builder with no characters in
         * it and an initial capacity of 16 characters.
         */
        StringBuilder sb1 = new StringBuilder();
        System.out.println("sb1 = " + sb1);
        System.out.println("sb1 capacity = " + sb1.capacity());

        System.out.println("-----------------------");

        /*
         * Constructs a string Builder with no characters in
         * it and the specified initial capacity.
         */
        StringBuilder sb2 = new StringBuilder(50);
        System.out.println("sb2 = " + sb2);
        System.out.println("sb2 capacity = " + sb2.capacity());

        System.out.println("-----------------------");

        /*
         * Constructs a string Builder initialized to the
         * contents of the specified string. The initial
         * capacity of the string Builder is 16 plus the
         * length of the string argument.
         */
        String str = "Hello";
        StringBuilder sb3 = new StringBuilder(str);
        System.out.println("sb3 = " + sb3);
        System.out.println("sb3 capacity = " + sb3.capacity());

        System.out.println("-----------------------");

        /*
         * Constructs a string Builder that contains the same
         * characters as the specified CharSequence. The
         * initial capacity of the string Builder is 16 plus
         * the length of the CharSequence argument.
         */
        CharSequence charSequence = new StringBuilder("Welcome");
        StringBuilder sb4 = new StringBuilder(charSequence);
        System.out.println("sb4 = " + sb4);
        System.out.println("sb4 capacity = " + sb4.capacity());

    }
}