Spring Framework example source code file (JdkVersion.java)

This example Spring Framework source code file (JdkVersion.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Spring Framework tags/keywords

java_13, java_14, java_14, java_15, java_15, java_16, java_16, java_17, java_17, jdkversion, string

The Spring Framework JdkVersion.java source code

/*
 * Copyright 2002-2007 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.core;

/**
 * Internal helper class used to find the Java/JDK version
 * that Spring is operating on, to allow for automatically
 * adapting to the present platform's capabilities.
 *
 * <p>Note that Spring requires JVM 1.4 or higher, as of Spring 2.5.
 *
 * @author Rod Johnson
 * @author Juergen Hoeller
 * @author Rick Evans
 */
public abstract class JdkVersion {

	/**
	 * Constant identifying the 1.3.x JVM (JDK 1.3).
	 */
	public static final int JAVA_13 = 0;

	/**
	 * Constant identifying the 1.4.x JVM (J2SE 1.4).
	 */
	public static final int JAVA_14 = 1;

	/**
	 * Constant identifying the 1.5 JVM (Java 5).
	 */
	public static final int JAVA_15 = 2;

	/**
	 * Constant identifying the 1.6 JVM (Java 6).
	 */
	public static final int JAVA_16 = 3;

	/**
	 * Constant identifying the 1.7 JVM (Java 7).
	 */
	public static final int JAVA_17 = 4;


	private static final String javaVersion;

	private static final int majorJavaVersion;

	static {
		javaVersion = System.getProperty("java.version");
		// version String should look like "1.4.2_10"
		if (javaVersion.indexOf("1.7.") != -1) {
			majorJavaVersion = JAVA_17;
		}
		else if (javaVersion.indexOf("1.6.") != -1) {
			majorJavaVersion = JAVA_16;
		}
		else if (javaVersion.indexOf("1.5.") != -1) {
			majorJavaVersion = JAVA_15;
		}
		else {
			// else leave 1.4 as default (it's either 1.4 or unknown)
			majorJavaVersion = JAVA_14;
		}
	}


	/**
	 * Return the full Java version string, as returned by
	 * <code>System.getProperty("java.version").
	 * @return the full Java version string
	 * @see System#getProperty(String)
	 */
	public static String getJavaVersion() {
		return javaVersion;
	}

	/**
	 * Get the major version code. This means we can do things like
	 * <code>if (getMajorJavaVersion() < JAVA_14).
	 * @return a code comparable to the JAVA_XX codes in this class
	 * @see #JAVA_13
	 * @see #JAVA_14
	 * @see #JAVA_15
	 * @see #JAVA_16
	 * @see #JAVA_17
	 */
	public static int getMajorJavaVersion() {
		return majorJavaVersion;
	}

	/**
	 * Convenience method to determine if the current JVM is at least Java 1.4.
	 * @return <code>true if the current JVM is at least Java 1.4
	 * @see #getMajorJavaVersion()
	 * @see #JAVA_14
	 * @see #JAVA_15
	 * @see #JAVA_16
	 * @see #JAVA_17
	 */
	public static boolean isAtLeastJava14() {
		return true;
	}

	/**
	 * Convenience method to determine if the current JVM is at least
	 * Java 1.5 (Java 5).
	 * @return <code>true if the current JVM is at least Java 1.5
	 * @see #getMajorJavaVersion()
	 * @see #JAVA_15
	 * @see #JAVA_16
	 * @see #JAVA_17
	 */
	public static boolean isAtLeastJava15() {
		return getMajorJavaVersion() >= JAVA_15;
	}

	/**
	 * Convenience method to determine if the current JVM is at least
	 * Java 1.6 (Java 6).
	 * @return <code>true if the current JVM is at least Java 1.6
	 * @see #getMajorJavaVersion()
	 * @see #JAVA_16
	 * @see #JAVA_17
	 */
	public static boolean isAtLeastJava16() {
		return getMajorJavaVersion() >= JAVA_16;
	}

}