How do I append and replace content of a StringBuffer?

A StringBuffer is like a String, but can be modified. StringBuffer are safe for use by multiple threads. The methods are synchronized where necessary so that all the operations on any particular instance behave as if they occur in some serial order that is consistent with the order of the method calls made by each of the individual threads involved.

As of release JDK 1.5, this class has been supplemented with an equivalent class designed for use by a single thread, StringBuilder. The StringBuilder class should generally be used in preference to this one, as it supports all of the same operations but it is faster, as it performs no synchronization.

package org.kodejava.example.lang;

public class StringBufferAppendReplace {
    public static void main(String[] args) {
        StringBuffer quote = new StringBuffer("an apple ");
        char a = 'a';
        String day = " day";
        StringBuffer sentences = new StringBuffer(" keep the doctor away");

        //
        // Append a character into StringBuffer
        //
        quote.append(a);
        System.out.println("quote = " + quote.toString());

        //
        // Append a string into StringBuffer
        //
        quote.append(day);
        System.out.println("quote = " + quote.toString());

        //
        // Append another StringBuffer
        //
        quote.append(sentences);
        System.out.println("quote = " + quote.toString());

        //
        // Replace a sub string from StringBuffer starting
        // from index = 3 to index = 8
        //
        quote.replace(3, 8, "orange");
        System.out.println("quote = " + quote.toString());
    }
}

Here is our program output:

quote = an apple a
quote = an apple a day
quote = an apple a day keep the doctor away
quote = an orange a day keep the doctor away
Wayan Saryada

Wayan Saryada

A programmer, runner, recreational diver, currently living in the island of Bali, Indonesia. Mostly programming in Java, creating web based application with Spring Framework, JPA, etc. If you need help on Java programming you can hire me on Fiverr.
Wayan Saryada

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