/*
* Copyright (c) 2008-2017, Hazelcast, Inc. All Rights Reserved.
*
* 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 com.hazelcast.internal.util;
/**
* Utility for checking runtime Java version.
*
*/
public enum JavaVersion {
UNKNOWN,
JAVA_1_6,
JAVA_1_7,
JAVA_1_8,
JAVA_1_9;
private static final JavaVersion CURRENT_VERSION = detectCurrentVersion();
/**
* Check if the current runtime version is at least the given version.
*
* @param version version to be compared against the current runtime version
* @return Return true if current runtime version of Java is the same or greater than given version.
* When the passed version is {@link #UNKNOWN} then it always returns true.
*/
public static boolean isAtLeast(JavaVersion version) {
return isAtLeast(CURRENT_VERSION, version);
}
private static JavaVersion detectCurrentVersion() {
String version = System.getProperty("java.version");
return parseVersion(version);
}
static JavaVersion parseVersion(String version) {
if (version == null) {
// this should not happen but it's better to stay on the safe side
return UNKNOWN;
}
if (version.startsWith("1.")) {
String withoutMajor = version.substring(2, version.length());
if (withoutMajor.startsWith("6")) {
return JAVA_1_6;
} else if (withoutMajor.startsWith("7")) {
return JAVA_1_7;
} else if (withoutMajor.startsWith("8")) {
return JAVA_1_8;
}
return UNKNOWN;
} else if (version.startsWith("9")) {
// from version 9 the string does not start with "1."
return JAVA_1_9;
}
return UNKNOWN;
}
static boolean isAtLeast(JavaVersion currentVersion, JavaVersion minVersion) {
return currentVersion.ordinal() >= minVersion.ordinal();
}
}