What is SystemUtils.isJavaVersionAtMost() in Java?
Overview
isJavaVersionAtMost() is a SystemUtils class that is used to check whether the Java version running in the system is, at most, the required version passed as an argument.
How to import SystemUtils
The definition of SystemUtils can be found in the Apache Commons Lang package, which we can add to the Maven project by adding the following dependency to the pom.xml file:
<dependency>
<groupId>org.apache.commons</groupId>
<artifactId>commons-lang3</artifactId>
<version>3.12.0</version>
</dependency>
For other versions of the
commons-langpackage, refer to the Maven Repository.
You can import the SystemUtils class as follows:
import org.apache.commons.lang3.SystemUtils;
Syntax
public static boolean isJavaVersionAtMost(final JavaVersion requiredVersion)
Parameters
final JavaVersion requiredVersion: This is the required version of Java.
JavaVersionis an enum representing all the versions of the Java specification.
Return value
This method returns true if the actual version of the system is less than or equal to the required version. Otherwise, it returns false.
Code
import org.apache.commons.lang3.JavaVersion;import org.apache.commons.lang3.SystemUtils;public class Main{public static void main(String[] args){// Example 1JavaVersion javaVersion = JavaVersion.JAVA_17;System.out.println("The current version of Java in the system is - " + System.getProperty("java.specification.version"));System.out.println("----------");System.out.printf("The output of SystemUtils.isJavaVersionAtMost() when the version '%s' is required - '%b'", javaVersion, SystemUtils.isJavaVersionAtMost(javaVersion));System.out.println();// Example 2javaVersion = JavaVersion.JAVA_9;System.out.printf("The output of SystemUtils.isJavaVersionAtMost() when the version '%s' is required - '%b'", javaVersion, SystemUtils.isJavaVersionAtMost(javaVersion));}}
Example 1
java version in the system = 11required java version = 17
The method returns true because the required version 17 is a greater version than 11.
Example 2
java version in the system = 11required java version = 9
The method returns false because the required version 9 is a lesser version than 11.
Output
The output of the code is as follows:
The current version of Java in the system is - 11
----------
The output of SystemUtils.isJavaVersionAtMost() when the version '17' is required - 'true'
The output of SystemUtils.isJavaVersionAtMost() when the version '9' is required - 'false'
