org.apache.shiro.util.JavaEnvironment Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.apache.shiro.util;
/**
* Internal helper class used to find the Java/JDK version
* that Shiro is operating within, to allow for automatically
* adapting to the present platform's capabilities.
*
* Note that Shiro does not support 1.2 or earlier JVMs - only 1.3 and later.
*
*
This class was borrowed and heavily based upon a nearly identical version found in
* the Spring Framework, with minor modifications.
* The original author names and copyright (Apache 2.0) has been left in place. A special
* thanks to Rod Johnson, Juergen Hoeller, and Rick Evans for making this available.
*
* @since 0.2
*/
public abstract class JavaEnvironment {
/**
* 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.
*/
public static final int JAVA_17 = 4;
/** The virtual machine version, i.e. System.getProperty("java.version");. */
private static final String version;
/**
* The virtual machine major version. For example, with a version of
* 1.5.6_10, this would be 1.5
*/
private static final int majorVersion;
/**
* Static code initialization block that sets the
* version and majorVersion Class constants
* upon initialization.
*/
static {
version = System.getProperty("java.version");
// version String should look like "1.4.2_10"
if (version.indexOf("1.7.") != -1) {
majorVersion = JAVA_17;
} else if (version.indexOf("1.6.") != -1) {
majorVersion = JAVA_16;
} else if (version.indexOf("1.5.") != -1) {
majorVersion = JAVA_15;
} else if (version.indexOf("1.4.") != -1) {
majorVersion = JAVA_14;
} else {
// else leave 1.3 as default (it's either 1.3 or unknown)
majorVersion = JAVA_13;
}
}
/**
* Return the full Java version string, as returned by
* System.getProperty("java.version").
*
* @return the full Java version string
* @see System#getProperty(String)
*/
public static String getVersion() {
return version;
}
/**
* Get the major version code. This means we can do things like
* if (getMajorVersion() < 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 getMajorVersion() {
return majorVersion;
}
/**
* Convenience method to determine if the current JVM is at least Java 1.4.
*
* @return true if the current JVM is at least Java 1.4
* @see #getMajorVersion()
* @see #JAVA_14
* @see #JAVA_15
* @see #JAVA_16
* @see #JAVA_17
*/
public static boolean isAtLeastVersion14() {
return getMajorVersion() >= JAVA_14;
}
/**
* Convenience method to determine if the current JVM is at least
* Java 1.5 (Java 5).
*
* @return true if the current JVM is at least Java 1.5
* @see #getMajorVersion()
* @see #JAVA_15
* @see #JAVA_16
* @see #JAVA_17
*/
public static boolean isAtLeastVersion15() {
return getMajorVersion() >= JAVA_15;
}
/**
* Convenience method to determine if the current JVM is at least
* Java 1.6 (Java 6).
*
* @return true if the current JVM is at least Java 1.6
* @see #getMajorVersion()
* @see #JAVA_15
* @see #JAVA_16
* @see #JAVA_17
*
* @since 1.2
*/
public static boolean isAtLeastVersion16() {
return getMajorVersion() >= JAVA_16;
}
}