    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.math.NumberUtils;
    020
    021/**
    022 * <p>An enum representing all the versions of the Java specification.
    023 * This is intended to mirror available values from the
    024 * <em>java.specification.version</em> System property. </p>
    025 *
    026 * @since 3.0
    027 */
    028public enum JavaVersion {
    029
    030    /**
    031     * The Java version reported by Android. This is not an official Java version number.
    032     */
    033    JAVA_0_9(1.5f, "0.9"),
    034
    035    /**
    036     * Java 1.1.
    037     */
    038    JAVA_1_1(1.1f, "1.1"),
    039
    040    /**
    041     * Java 1.2.
    042     */
    043    JAVA_1_2(1.2f, "1.2"),
    044
    045    /**
    046     * Java 1.3.
    047     */
    048    JAVA_1_3(1.3f, "1.3"),
    049
    050    /**
    051     * Java 1.4.
    052     */
    053    JAVA_1_4(1.4f, "1.4"),
    054
    055    /**
    056     * Java 1.5.
    057     */
    058    JAVA_1_5(1.5f, "1.5"),
    059
    060    /**
    061     * Java 1.6.
    062     */
    063    JAVA_1_6(1.6f, "1.6"),
    064
    065    /**
    066     * Java 1.7.
    067     */
    068    JAVA_1_7(1.7f, "1.7"),
    069
    070    /**
    071     * Java 1.8.
    072     */
    073    JAVA_1_8(1.8f, "1.8"),
    074
    075    /**
    076     * Java 1.9.
    077     *
    078     * @deprecated As of release 3.5, replaced by {@link #JAVA_9}
    079     */
    080    @Deprecated
    081    JAVA_1_9(9.0f, "9"),
    082
    083    /**
    084     * Java 9.
    085     *
    086     * @since 3.5
    087     */
    088    JAVA_9(9.0f, "9"),
    089
    090    /**
    091     * Java 10.
    092     *
    093     * @since 3.7
    094     */
    095    JAVA_10(10.0f, "10"),
    096
    097    /**
    098     * Java 11.
    099     *
    100     * @since 3.8
    101     */
    102    JAVA_11(11.0f, "11"),
    103
    104    /**
    105     * Java 12.
    106     *
    107     * @since 3.9
    108     */
    109    JAVA_12(12.0f, "12"),
    110
    111    /**
    112     * Java 13.
    113     *
    114     * @since 3.9
    115     */
    116    JAVA_13(13.0f, "13"),
    117
    118    /**
    119     * Java 14.
    120     *
    121     * @since 3.11
    122     */
    123    JAVA_14(14.0f, "14"),
    124
    125    /**
    126     * Java 15.
    127     *
    128     * @since 3.11
    129     */
    130    JAVA_15(15.0f, "15"),
    131
    132    /**
    133     * Java 16.
    134     *
    135     * @since 3.11
    136     */
    137    JAVA_16(16.0f, "16"),
    138
    139    /**
    140     * Java 17.
    141     *
    142     * @since 3.12.0
    143     */
    144    JAVA_17(17.0f, "17"),
    145
    146    /**
    147     * The most recent java version. Mainly introduced to avoid to break when a new version of Java is used.
    148     */
    149    JAVA_RECENT(maxVersion(), Float.toString(maxVersion()));
    150
    151    /**
    152     * The float value.
    153     */
    154    private final float value;
    155
    156    /**
    157     * The standard name.
    158     */
    159    private final String name;
    160
    161    /**
    162     * Constructor.
    163     *
    164     * @param value  the float value
    165     * @param name  the standard name, not null
    166     */
    167    JavaVersion(final float value, final String name) {
    168        this.value = value;
    169        this.name = name;
    170    }
    171
    172    //-----------------------------------------------------------------------
    173    /**
    174     * <p>Whether this version of Java is at least the version of Java passed in.</p>
    175     *
    176     * <p>For example:<br>
    177     *  {@code myVersion.atLeast(JavaVersion.JAVA_1_4)}<p>
    178     *
    179     * @param requiredVersion  the version to check against, not null
    180     * @return true if this version is equal to or greater than the specified version
    181     */
    182    public boolean atLeast(final JavaVersion requiredVersion) {
    183        return this.value >= requiredVersion.value;
    184    }
    185
    186    //-----------------------------------------------------------------------
    187    /**
    188     * <p>Whether this version of Java is at most the version of Java passed in.</p>
    189     *
    190     * <p>For example:<br>
    191     *  {@code myVersion.atMost(JavaVersion.JAVA_1_4)}<p>
    192     *
    193     * @param requiredVersion  the version to check against, not null
    194     * @return true if this version is equal to or greater than the specified version
    195     * @since 3.9
    196     */
    197    public boolean atMost(final JavaVersion requiredVersion) {
    198        return this.value <= requiredVersion.value;
    199    }
    200
    201    /**
    202     * Transforms the given string with a Java version number to the
    203     * corresponding constant of this enumeration class. This method is used
    204     * internally.
    205     *
    206     * @param nom the Java version as string
    207     * @return the corresponding enumeration constant or <b>null</b> if the
    208     * version is unknown
    209     */
    210    // helper for static importing
    211    static JavaVersion getJavaVersion(final String nom) {
    212        return get(nom);
    213    }
    214
    215    /**
    216     * Transforms the given string with a Java version number to the
    217     * corresponding constant of this enumeration class. This method is used
    218     * internally.
    219     *
    220     * @param versionStr the Java version as string
    221     * @return the corresponding enumeration constant or <b>null</b> if the
    222     * version is unknown
    223     */
    224    static JavaVersion get(final String versionStr) {
    225        if (versionStr == null) {
    226            return null;
    227        }
    228        switch (versionStr) {
    229        case "0.9":
    230            return JAVA_0_9;
    231        case "1.1":
    232            return JAVA_1_1;
    233        case "1.2":
    234            return JAVA_1_2;
    235        case "1.3":
    236            return JAVA_1_3;
    237        case "1.4":
    238            return JAVA_1_4;
    239        case "1.5":
    240            return JAVA_1_5;
    241        case "1.6":
    242            return JAVA_1_6;
    243        case "1.7":
    244            return JAVA_1_7;
    245        case "1.8":
    246            return JAVA_1_8;
    247        case "9":
    248            return JAVA_9;
    249        case "10":
    250            return JAVA_10;
    251        case "11":
    252            return JAVA_11;
    253        case "12":
    254            return JAVA_12;
    255        case "13":
    256            return JAVA_13;
    257        case "14":
    258            return JAVA_14;
    259        case "15":
    260            return JAVA_15;
    261        case "16":
    262            return JAVA_16;
    263        case "17":
    264            return JAVA_17;
    265        default:
    266            final float v = toFloatVersion(versionStr);
    267            if ((v - 1.) < 1.) { // then we need to check decimals > .9
    268                final int firstComma = Math.max(versionStr.indexOf('.'), versionStr.indexOf(','));
    269                final int end = Math.max(versionStr.length(), versionStr.indexOf(',', firstComma));
    270                if (Float.parseFloat(versionStr.substring(firstComma + 1, end)) > .9f) {
    271                    return JAVA_RECENT;
    272                }
    273            } else if (v > 10) {
    274                return JAVA_RECENT;
    275            }
    276            return null;
    277        }
    278    }
    279
    280    //-----------------------------------------------------------------------
    281    /**
    282     * <p>The string value is overridden to return the standard name.</p>
    283     *
    284     * <p>For example, {@code "1.5"}.</p>
    285     *
    286     * @return the name, not null
    287     */
    288    @Override
    289    public String toString() {
    290        return name;
    291    }
    292
    293    /**
    294     * Gets the Java Version from the system or 99.0 if the {@code java.specification.version} system property is not set.
    295     *
    296     * @return the value of {@code java.specification.version} system property or 99.0 if it is not set.
    297     */
    298    private static float maxVersion() {
    299        final float v = toFloatVersion(System.getProperty("java.specification.version", "99.0"));
    300        if (v > 0) {
    301            return v;
    302        }
    303        return 99f;
    304    }
    305
    306    /**
    307     * Parses a float value from a String.
    308     *
    309     * @param value the String to parse.
    310     * @return the float value represented by the string or -1 if the given String can not be parsed.
    311     */
    312    private static float toFloatVersion(final String value) {
    313        final int defaultReturnValue = -1;
    314        if (value.contains(".")) {
    315            final String[] toParse = value.split("\\.");
    316            if (toParse.length >= 2) {
    317                return NumberUtils.toFloat(toParse[0] + '.' + toParse[1], defaultReturnValue);
    318            }
    319        } else {
    320            return NumberUtils.toFloat(value, defaultReturnValue);
    321        }
    322        return defaultReturnValue;
    323    }
    324}