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 java.util.HashMap;
020import java.util.Map;
021import java.util.stream.Stream;
022
023import org.apache.commons.lang3.arch.Processor;
024
025/**
026 * An utility class for the os.arch System Property. The class defines methods for
027 * identifying the architecture of the current JVM.
028 * <p>
029 * Important: The os.arch System Property returns the architecture used by the JVM
030 * not of the operating system.
031 * </p>
032 * @since 3.6
033 */
034public class ArchUtils {
035
036    private static final Map<String, Processor> ARCH_TO_PROCESSOR;
037
038    static {
039        ARCH_TO_PROCESSOR = new HashMap<>();
040        init();
041    }
042
043    private static void init() {
044        init_X86_32Bit();
045        init_X86_64Bit();
046        init_IA64_32Bit();
047        init_IA64_64Bit();
048        init_PPC_32Bit();
049        init_PPC_64Bit();
050    }
051
052    private static void init_X86_32Bit() {
053        final Processor processor = new Processor(Processor.Arch.BIT_32, Processor.Type.X86);
054        addProcessors(processor, "x86", "i386", "i486", "i586", "i686", "pentium");
055    }
056
057    private static void init_X86_64Bit() {
058        final Processor processor = new Processor(Processor.Arch.BIT_64, Processor.Type.X86);
059        addProcessors(processor, "x86_64", "amd64", "em64t", "universal");
060    }
061
062    private static void init_IA64_32Bit() {
063        final Processor processor = new Processor(Processor.Arch.BIT_32, Processor.Type.IA_64);
064        addProcessors(processor, "ia64_32", "ia64n");
065    }
066
067    private static void init_IA64_64Bit() {
068        final Processor processor = new Processor(Processor.Arch.BIT_64, Processor.Type.IA_64);
069        addProcessors(processor, "ia64", "ia64w");
070    }
071
072    private static void init_PPC_32Bit() {
073        final Processor processor = new Processor(Processor.Arch.BIT_32, Processor.Type.PPC);
074        addProcessors(processor, "ppc", "power", "powerpc", "power_pc", "power_rs");
075    }
076
077    private static void init_PPC_64Bit() {
078        final Processor processor = new Processor(Processor.Arch.BIT_64, Processor.Type.PPC);
079        addProcessors(processor, "ppc64", "power64", "powerpc64", "power_pc64", "power_rs64");
080    }
081
082    /**
083     * Adds the given {@link Processor} with the given key {@link String} to the map.
084     *
085     * @param key The key as {@link String}.
086     * @param processor The {@link Processor} to add.
087     * @throws IllegalStateException If the key already exists.
088     */
089    private static void addProcessor(final String key, final Processor processor) {
090        if (ARCH_TO_PROCESSOR.containsKey(key)) {
091            throw new IllegalStateException("Key " + key + " already exists in processor map");
092        }
093        ARCH_TO_PROCESSOR.put(key, processor);
094    }
095
096    /**
097     * Adds the given {@link Processor} with the given keys to the map.
098     *
099     * @param keys The keys.
100     * @param processor The {@link Processor} to add.
101     * @throws IllegalStateException If the key already exists.
102     */
103    private static void addProcessors(final Processor processor, final String... keys) {
104        Stream.of(keys).forEach(e -> addProcessor(e, processor));
105    }
106
107    /**
108     * Returns a {@link Processor} object of the current JVM.
109     *
110     * <p>
111     * Important: The os.arch System Property returns the architecture used by the JVM
112     * not of the operating system.
113     * </p>
114     *
115     * @return A {@link Processor} when supported, else {@code null}.
116     */
117    public static Processor getProcessor() {
118        return getProcessor(SystemUtils.OS_ARCH);
119    }
120
121    /**
122     * Returns a {@link Processor} object the given value {@link String}. The {@link String} must be
123     * like a value returned by the os.arch System Property.
124     *
125     * @param value A {@link String} like a value returned by the os.arch System Property.
126     * @return A {@link Processor} when it exists, else {@code null}.
127     */
128    public static Processor getProcessor(final String value) {
129        return ARCH_TO_PROCESSOR.get(value);
130    }
131
132}