| /* |
| * 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.cassandra.utils; |
| |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| /** |
| * Utility method to retrieve information about the JRE. |
| */ |
| public final class JavaUtils |
| { |
| private static final Logger logger = LoggerFactory.getLogger(JavaUtils.class); |
| |
| /** |
| * Checks if the specified JRE support ExitOnOutOfMemory and CrashOnOutOfMemory. |
| * @param jreVersion the JRE version |
| * @return {@code true} if the running JRE support ExitOnOutOfMemory and CrashOnOutOfMemory or if the exact version |
| * cannot be determined, {@code false} otherwise. |
| */ |
| public static boolean supportExitOnOutOfMemory(String jreVersion) |
| { |
| try |
| { |
| int version = parseJavaVersion(jreVersion); |
| |
| if (version > 8) |
| return true; |
| |
| int update = parseUpdateForPre9Versions(jreVersion); |
| // The ExitOnOutOfMemory and CrashOnOutOfMemory are supported since the version 7u101 and 8u92 |
| return (version == 7 && update >= 101) || (version == 8 && update >= 92); |
| } |
| catch (Exception e) |
| { |
| logger.error("Some JRE information could not be retrieved for the JRE version: " + jreVersion, e); |
| // We will continue assuming that the version supports ExitOnOutOfMemory and CrashOnOutOfMemory. |
| return true; |
| } |
| } |
| |
| /** |
| * Parses an Oracle JRE Version to extract the java version number. |
| * <p> The parsing rules are based on the following |
| * <a href='http://www.oracle.com/technetwork/java/javase/versioning-naming-139433.html'>String Naming Convention</a> and |
| * <a href='http://openjdk.java.net/jeps/223'>JEP 223: New Version-String Scheme</a>.</p> |
| * @param jreVersion the Oracle JRE Version |
| * @return the java version number |
| * @throws NumberFormatException if the version cannot be retrieved |
| */ |
| private static int parseJavaVersion(String jreVersion) |
| { |
| String version; |
| if (jreVersion.startsWith("1.")) |
| { |
| version = jreVersion.substring(2, 3); // Pre 9 version |
| } |
| else |
| { |
| // Version > = 9 |
| int index = jreVersion.indexOf('.'); |
| |
| if (index < 0) |
| { |
| // Does not have a minor version so we need to check for EA release |
| index = jreVersion.indexOf('-'); |
| if (index < 0) |
| index = jreVersion.length(); |
| } |
| version = jreVersion.substring(0, index); |
| } |
| return Integer.parseInt(version); |
| } |
| |
| /** |
| * Parses an Oracle JRE Version < 9 to extract the update version. |
| * <p> The parsing rules are based on the following |
| * <a href='http://www.oracle.com/technetwork/java/javase/versioning-naming-139433.html'>String Naming Convention</a>.</p> |
| * @param jreVersion the Oracle JRE Version |
| * @return the update version |
| * @throws NumberFormatException if the update cannot be retrieved |
| */ |
| private static int parseUpdateForPre9Versions(String jreVersion) |
| { |
| // Handle non GA versions |
| int dashSeparatorIndex = jreVersion.indexOf('-'); |
| if (dashSeparatorIndex > 0) |
| jreVersion = jreVersion.substring(0, dashSeparatorIndex); |
| |
| int updateSeparatorIndex = jreVersion.indexOf('_'); |
| if (updateSeparatorIndex < 0) |
| return 0; // Initial release |
| |
| return Integer.parseInt(jreVersion.substring(updateSeparatorIndex + 1)); |
| } |
| |
| private JavaUtils() |
| { |
| } |
| } |