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}