August 14, 2022

How to copy an Array in Java

The methods described below are only applicable to one dimensional arrays. Arrays inherit methods from Object class, and Object.clone() is one of them. If you need to copy an Array as it is then this is the method you should use. In Arrays class there are two methods that copy an array fully or partially: copyOf() method and copyOfRange() method. With System.arraycopy() you can control the range of elements from the source array that you want to copy,and the destined position.

How to copy an Array in Java Read More

Java – How to convert Array to Stream

In Java 8, you can either use Arrays.stream or Stream.of to convert an Array into a Stream. For object arrays, both Arrays.stream and Stream.of returns the same output. For object arrays, the Stream.of method is calling the Arrays.stream internally. For primitive array, the Arrays.stream and Stream.of will return different output. For object arrays, both are calling the same Arrays.stream. For primitive arrays, I prefer Arrays.stream as well, because it returns fixed size IntStream directly, easier to manipulate it.

Java – How to convert Array to Stream Read More

How to print an Array in Java

In this article, we will show you a few ways to print a Java Array. We can use JDK 1.5 Arrays.toString to print a simple array and Arrays.deepToString for 2d or nested arrays. In Java 8, we can use Stream APIs to convert a simple array into a stream and print it out one by one; for 2d or nested array, we need to use flatMap. We also can use the Java 8 Stream APIs – Collectors.joining to join arrays into a string and print it out. We can use the Jackson API ObjectMapper to print anything.

How to print an Array in Java Read More

Java – How to join Arrays

In this article, we will show you a few ways to join a Java Array: 1 – Apache Commons Lang – ArrayUtils, 2 – Java API, 3 – Java 8 Stream. The simplest way is add the Apache Commons Lang library, and use ArrayUtils. addAll to join arrays. This method supports both primitive and object type arrays. Pure Java API example, supports both primitive and generic types. Java 8 Stream example on using concat method to join arrays.

Java – How to join Arrays Read More