001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.apache.commons.lang3;
018
019import org.apache.commons.lang3.arch.Processor;
020
021import java.util.HashMap;
022import java.util.Map;
023
024/**
025 * An utility class for the os.arch System Property. The class defines methods for
026 * identifying the architecture of the current JVM.
027 * <p>
028 * Important: The os.arch System Property returns the architecture used by the JVM
029 * not of the operating system.
030 * </p>
031 * @since 3.6
032 */
033public class ArchUtils {
034
035    private static final Map<String, Processor> ARCH_TO_PROCESSOR;
036
037    static {
038        ARCH_TO_PROCESSOR = new HashMap<>();
039        init();
040    }
041
042    private static void init() {
043        init_X86_32Bit();
044        init_X86_64Bit();
045        init_IA64_32Bit();
046        init_IA64_64Bit();
047        init_PPC_32Bit();
048        init_PPC_64Bit();
049    }
050
051    private static void init_X86_32Bit() {
052        Processor processor = new Processor(Processor.Arch.BIT_32, Processor.Type.X86);
053        addProcessors(processor, "x86", "i386", "i486", "i586", "i686", "pentium");
054    }
055
056    private static void init_X86_64Bit() {
057        Processor processor = new Processor(Processor.Arch.BIT_64, Processor.Type.X86);
058        addProcessors(processor, "x86_64", "amd64", "em64t", "universal");
059    }
060
061    private static void init_IA64_32Bit() {
062        Processor processor = new Processor(Processor.Arch.BIT_32, Processor.Type.IA_64);
063        addProcessors(processor, "ia64_32", "ia64n");
064    }
065
066    private static void init_IA64_64Bit() {
067        Processor processor = new Processor(Processor.Arch.BIT_64, Processor.Type.IA_64);
068        addProcessors(processor, "ia64", "ia64w");
069    }
070
071    private static void init_PPC_32Bit() {
072        Processor processor = new Processor(Processor.Arch.BIT_32, Processor.Type.PPC);
073        addProcessors(processor, "ppc", "power", "powerpc", "power_pc", "power_rs");
074    }
075
076    private static void init_PPC_64Bit() {
077        Processor processor = new Processor(Processor.Arch.BIT_64, Processor.Type.PPC);
078        addProcessors(processor, "ppc64", "power64", "powerpc64", "power_pc64", "power_rs64");
079    }
080
081    /**
082     * Adds the given {@link Processor} with the given key {@link String} to the map.
083     *
084     * @param key The key as {@link String}.
085     * @param processor The {@link Processor} to add.
086     * @throws IllegalStateException If the key already exists.
087     */
088    private static void addProcessor(String key, Processor processor) throws IllegalStateException {
089        if (!ARCH_TO_PROCESSOR.containsKey(key)) {
090            ARCH_TO_PROCESSOR.put(key, processor);
091        } else {
092            String msg = "Key " + key + " already exists in processor map";
093            throw new IllegalStateException(msg);
094        }
095    }
096
097    /**
098     * Adds the given {@link Processor} with the given keys to the map.
099     *
100     * @param keys The keys.
101     * @param processor The {@link Processor} to add.
102     * @throws IllegalStateException If the key already exists.
103     */
104    private static void addProcessors(Processor processor, String... keys) throws IllegalStateException {
105        for (String key : keys) {
106            addProcessor(key, processor);
107        }
108    }
109
110    /**
111     * Returns a {@link Processor} object of the current JVM.
112     *
113     * <p>
114     * Important: The os.arch System Property returns the architecture used by the JVM
115     * not of the operating system.
116     * </p>
117     *
118     * @return A {@link Processor} when supported, else <code>null</code>.
119     */
120    public static Processor getProcessor() {
121        return getProcessor(SystemUtils.OS_ARCH);
122    }
123
124    /**
125     * Returns a {@link Processor} object the given value {@link String}. The {@link String} must be
126     * like a value returned by the os.arch System Property.
127     *
128     * @param value A {@link String} like a value returned by the os.arch System Property.
129     * @return A {@link Processor} when it exists, else <code>null</code>.
130     */
131    public static Processor getProcessor(String value) {
132        return ARCH_TO_PROCESSOR.get(value);
133    }
134
135}