Java Program To Reverse A String Without Using String Inbuilt Function reverse()

1. Introduction

In this tutorial, You'll learn how to write a java program to reverse a string without using string inbuilt function reverse().
This is a very common interview question that can be asked in many forms as below.

A) java program to reverse a string without using string inbuilt function
B) java program to reverse a string using recursion
C) java program to reverse a string without using the reverse method
C) Try using other classes of Java API (Except String).



The interviewer's main intention is not to use the String class reverse() method.

Anonymous Comparator In Java For Sorting

1. Overview

In this tutorial, We'll learn how to sort arrays or lists using an anonymous comparator in java.

A complete guide on how to use comparator in java?

Anonymous class means creating the class and providing the implementation at the same without a class name.

For example, we have an interface Job and it has the method post() to post the new job. here, a new job1 instance is created for the implementation class of Job interface without a class name.

Example 1

interface Job {
	void post();
}

Job job1 = new Job() {

	@Override
	public void post() {
		System.out.println("Posting job 1 now");

}

This is similar to the anonymous implementation of the abstract class or interface. This is the actual implementation of the Comparator without creating a class and implementing the Comparator interface.

Java Thread.join() Examples to Wait for Another Thread

1. Introduction

In this tutorial, We'll learn how to use Thread.join() method in java. And also how to join the multiple threads at one place after completing the execution of all threads or one thread or any other threads.

join() method is part of the Thread class and it is part of the java.lang package. All the classes in java.lang package is not needed to add import statements. So, directly you can use it in the programs. join() is mainly used to sleep or wait the current thread until completion of another thread execution.

Similar to the wait() and notify(), join() also widely used in the thread intercommunication.

2. Thread.join() Syntax

below is the syntax from Thread API. join() method is an overloaded method so we should be careful which method should be used.

public final void join() throws InterruptedException

public final void join(long millis) throws InterruptedException

public final void join(long millis, int nanos) throws InterruptedException

Java 8 String API also has join() method.

Java Program To Find First Non-Repeated Character In String (5 ways)

1. Overview

In this article, We will be learning and understanding the various ways to find the first non repeated character in a given string in various ways along with Java 8 Streams. Many programs may face this type of question in programming interviews or face to face round.
Let us start with the simple approach and next discover the partial and single iteration through the string.

Latest 20+ JMS Interview Questions and Answers

1. Introduction

In this tutorial, We'll learn about JMS interview questions that are frequently asked in 2020. As part of the interview, There are chances to ask some of the questions on JMS area if you have 6 years plus. But, even less experience, it is good to have in the profile on JMS experience. The interviewer will check as messaging is a key aspect of enterprise Java development.
JMS is a popular open-source Messaging API and many vendors such as Apache Active MQ, Websphere MQ, Sonic MQ provides an implementation of Java messaging API or JMS.


Usually, Any interview starts with a basic. If all questions are answered properly then we will go onto the JMS experience project-based questions.

Basics mean What is Topic? What is the Queue? What is Publisher? What is Subscriber? What are a Publisher and Subscriber model? How to configure MQ?
Next level means Questions on a project where you have implemented JMS concepts?

Java String startsWith() Examples

1. Overview

In this article, You'll learn how to Test if this string starts with the specified prefix. 

Method startsWith() is case-sensitive.

String API is added with a method startsWith() that returns true if the character sequence represented by the argument is a prefix of the character sequence represented by this string; false otherwise. Note also that true will be returned if the argument is an empty string or is equal to this String object as determined by the equals(Object) method.

This method works exactly opposite to the String endsWith() method.

Java 8 Default and Static Methods - Interface New Concepts

1. Overview

In this Java 8 new concept, We are going to learn today what is the Default Method in Java 8 and why it is introduced in java 8 changes.

Java 8 introduces a new concept of default method implementation in interfaces. This capability is added for backward compatibility so that old interfaces can be used to leverage the lambda expression capability of Java 8. For example, the List interface is not having the forEach() method. If they add this method as an abstract method then all List implementation classes must have to provide the implementation since it is common functionality to iterate the list. So they had to introduce this concept to enhance features and support for the backward classes.