Huong Dan Java - Page 70 of 78 - Java development tutorials

Method iterate() of Stream object in Java

In Java 8, the iterate() method has been introduced and it has only two parameters and will help us to create an infinite stream. Content:

public static<T> Stream<T> iterate(final T seed, final UnaryOperator<T> f)

1	public static<T> Stream<T> iterate(final T seed, final UnaryOperator<T> f)

Example:

package com.huongdanjava.javastream;

import java.util.stream.Stream;

public class Example {

	public static void main(String[] args) {
		Stream.iterate(1, i -> i + 1).forEach(System.out::println);
	}
}

package com.huongdanjava.javastream;

import java.util.stream.Stream;

public class Example {

public static void main(String[] args) {

Stream.iterate(1, i -> i + 1).forEach(System.out::println);

}

When running the above example, you will see that a Stream object contains endless numbers beginning at… Read More

Method ofNullable() of Stream object in Java

8 years ago by Khanh NguyenJava Basic

This method was added from Java 9.

static<T> Stream<T> ofNullable(T t)

1	static<T> Stream<T> ofNullable(T t)

This method will return the Stream object of an element in case this element is not null; if it is null, it returns an empty Stream. Example:

package com.huongdanjava.javaexample;

import java.util.stream.Stream;

public class Example {

	public static void main(String[] args) {
		String s = null;
		Stream.ofNullable(s).forEach(System.out::println);
	}
}

package com.huongdanjava.javaexample;

import java.util.stream.Stream;

public class Example {

public static void main(String[] args) {

String s = null;

Stream.ofNullable(s).forEach(System.out::println);

}

When you run the above code, it will print… Read More

Method dropWhile() of Stream object in Java

8 years ago by Khanh NguyenJava Basic

This method was added from Java 9.

default Stream<T> dropWhile(Predicate<? super T> predicate)

1	default Stream<T> dropWhile(Predicate<? super T> predicate)

This method also has the parameter Predicate interface and its function is the opposite of the takeWhile() method. This method also passes each element in your Stream object from left to right and ignores all elements that… Read More

Method takeWhile() of Stream object in Java

8 years ago by Khanh NguyenJava Basic

This method was added from Java 9.

default Stream<T> takeWhile(Predicate<? super T> predicate)

1	default Stream<T> takeWhile(Predicate<? super T> predicate)

The parameter of this method is the Predicate interface and this method takes the elements in your Stream object from left to right, until the condition of the Predicate object is no longer fulfilled. Example:

package com.huongdanjava.javastream;

import java.util.stream.Stream;

public class Example {

	public static void main(String[] args) {
		Stream.of(1,2,3,4,5,6,7,8,9,10)
			.takeWhile(i -> i < 5)
			.forEach(System.out::println);
	}
}

package com.huongdanjava.javastream;

import java.util.stream.Stream;

public class Example {

public static void main(String[] args) {

Stream.of(1,2,3,4,5,6,7,8,9,10)

.takeWhile(i -> i < 5)

.forEach(System.out::println);

}

In… Read More

Multithreading with Callable and Future in Java

8 years ago by Khanh NguyenJava Basic

Multithreading is the notion of handling program actions that do not take place in the program’s main Thread, which is handled by many different Threads. This concept will make the processing of the program faster. We have many ways to implement multithreading in Java, but… Read More

Reactive Streams in Java

8 years ago by Khanh NguyenJava Basic

Reactive Streams are a concept that defines the mechanism for handling streams asynchronously with non-blocking back pressure. Back pressure here, we can understand that there is too much work to do at the same time, then it should lead to overload. Non-blocking back pressure means… Read More

Create Connector using Devkit in Anypoint Studio

8 years ago by Khanh NguyenMule ESB

In the previous tutorial, I showed you how to create a new Anypoint Connector Project to start creating a new custom Connector and use it in your Mule application. In this tutorial, I will go into details how to create Connector using Devkit in Anypoint… Read More

Introduce about JShell in Java

8 years ago by Khanh NguyenJava Basic

If you have ever worked with some languages like Python, Scala, you may know we can write code and execute code for those languages using only the command line. This will allow us to test some code without having to do a lot of things,… Read More

Install Anypoint Devkit Plugin in Anypoint Studio

8 years ago by Khanh NguyenMule ESB

Anypoint Devkit Plugin is not installed with Anypoint Studio by default. So, if you want to create a new Connector for using in your Mule application, the first thing we need to do: install Anypoint Devkit Plugin for Anypoint Studio. In this tutorial, I will… Read More

Introduction about Optional object in Java

8 years ago by Khanh NguyenJava Basic

In the previous tutorial about NullPointerException in Java, I have presented to you some cases where NPE can occur and how to deal with them to avoid. From Java 8, we have another way to avoid NullPointerException, that will use the Optional object. What is… Read More