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 * 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.
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     * Java 18.
148     *
149     * @since 3.13.0
150     */
151    JAVA_18(18.0f, "18"),
152
153    /**
154     * Java 19.
155     *
156     * @since 3.13.0
157     */
158    JAVA_19(19.0f, "19"),
159
160    /**
161     * Java 20.
162     *
163     * @since 3.13.0
164     */
165    JAVA_20(20, "20"),
166
167    /**
168     * Java 21.
169     *
170     * @since 3.13.0
171     */
172    JAVA_21(21, "21"),
173
174    /**
175     * Java 22.
176     *
177     * @since 3.15.0
178     */
179    JAVA_22(22, "22"),
180
181    /**
182     * The most recent Java version. Mainly introduced to avoid to break when a new version of Java is used.
183     */
184    JAVA_RECENT(maxVersion(), Float.toString(maxVersion()));
185
186    /**
187     * The regex to split version strings.
188     */
189    private static final String VERSION_SPLIT_REGEX = "\\.";
190
191    /**
192     * Transforms the given string with a Java version number to the
193     * corresponding constant of this enumeration class. This method is used
194     * internally.
195     *
196     * @param versionStr the Java version as string
197     * @return the corresponding enumeration constant or <b>null</b> if the
198     * version is unknown
199     */
200    static JavaVersion get(final String versionStr) {
201        if (versionStr == null) {
202            return null;
203        }
204        switch (versionStr) {
205        case "0.9":
206            return JAVA_0_9;
207        case "1.1":
208            return JAVA_1_1;
209        case "1.2":
210            return JAVA_1_2;
211        case "1.3":
212            return JAVA_1_3;
213        case "1.4":
214            return JAVA_1_4;
215        case "1.5":
216            return JAVA_1_5;
217        case "1.6":
218            return JAVA_1_6;
219        case "1.7":
220            return JAVA_1_7;
221        case "1.8":
222            return JAVA_1_8;
223        case "9":
224            return JAVA_9;
225        case "10":
226            return JAVA_10;
227        case "11":
228            return JAVA_11;
229        case "12":
230            return JAVA_12;
231        case "13":
232            return JAVA_13;
233        case "14":
234            return JAVA_14;
235        case "15":
236            return JAVA_15;
237        case "16":
238            return JAVA_16;
239        case "17":
240            return JAVA_17;
241        case "18":
242            return JAVA_18;
243        case "19":
244            return JAVA_19;
245        case "20":
246            return JAVA_20;
247        case "21":
248            return JAVA_21;
249        case "22":
250            return JAVA_22;
251        default:
252            final float v = toFloatVersion(versionStr);
253            if (v - 1. < 1.) { // then we need to check decimals > .9
254                final int firstComma = Math.max(versionStr.indexOf('.'), versionStr.indexOf(','));
255                final int end = Math.max(versionStr.length(), versionStr.indexOf(',', firstComma));
256                if (Float.parseFloat(versionStr.substring(firstComma + 1, end)) > .9f) {
257                    return JAVA_RECENT;
258                }
259            } else if (v > 10) {
260                return JAVA_RECENT;
261            }
262            return null;
263        }
264    }
265
266    /**
267     * Transforms the given string with a Java version number to the
268     * corresponding constant of this enumeration class. This method is used
269     * internally.
270     *
271     * @param versionStr the Java version as string
272     * @return the corresponding enumeration constant or <b>null</b> if the
273     * version is unknown
274     */
275    static JavaVersion getJavaVersion(final String versionStr) {
276        return get(versionStr);
277    }
278
279    /**
280     * Gets the Java Version from the system or 99.0 if the {@code java.specification.version} system property is not set.
281     *
282     * @return the value of {@code java.specification.version} system property or 99.0 if it is not set.
283     */
284    private static float maxVersion() {
285        final float v = toFloatVersion(SystemProperties.getJavaSpecificationVersion("99.0"));
286        return v > 0 ? v : 99f;
287    }
288
289    static String[] split(final String value) {
290        return value.split(VERSION_SPLIT_REGEX);
291    }
292
293    /**
294     * Parses a float value from a String.
295     *
296     * @param value the String to parse.
297     * @return the float value represented by the string or -1 if the given String can not be parsed.
298     */
299    private static float toFloatVersion(final String value) {
300        final int defaultReturnValue = -1;
301        if (!value.contains(".")) {
302            return NumberUtils.toFloat(value, defaultReturnValue);
303        }
304        final String[] toParse = split(value);
305        if (toParse.length >= 2) {
306            return NumberUtils.toFloat(toParse[0] + '.' + toParse[1], defaultReturnValue);
307        }
308        return defaultReturnValue;
309    }
310
311    /**
312     * The float value.
313     */
314    private final float value;
315
316    /**
317     * The standard name.
318     */
319    private final String name;
320
321    /**
322     * Constructs a new instance.
323     *
324     * @param value  the float value
325     * @param name  the standard name, not null
326     */
327    JavaVersion(final float value, final String name) {
328        this.value = value;
329        this.name = name;
330    }
331
332    /**
333     * Tests whether this version of Java is at least the version of Java passed in.
334     *
335     * <p>For example:<br>
336     *  {@code myVersion.atLeast(JavaVersion.JAVA_1_4)}</p>
337     *
338     * @param requiredVersion  the version to check against, not null
339     * @return true if this version is equal to or greater than the specified version
340     */
341    public boolean atLeast(final JavaVersion requiredVersion) {
342        return this.value >= requiredVersion.value;
343    }
344
345    /**
346     * Tests whether this version of Java is at most the version of Java passed in.
347     *
348     * <p>For example:<br>
349     *  {@code myVersion.atMost(JavaVersion.JAVA_1_4)}</p>
350     *
351     * @param requiredVersion  the version to check against, not null
352     * @return true if this version is equal to or greater than the specified version
353     * @since 3.9
354     */
355    public boolean atMost(final JavaVersion requiredVersion) {
356        return this.value <= requiredVersion.value;
357    }
358
359    /**
360     * The string value is overridden to return the standard name.
361     *
362     * <p>For example, {@code "1.5"}.</p>
363     *
364     * @return the name, not null
365     */
366    @Override
367    public String toString() {
368        return name;
369    }
370}