001    package cpw.mods.fml.common.versioning;
002    /*
003     * Modifications by cpw under LGPL 2.1 or later
004     */
005    
006    /*
007     * Licensed to the Apache Software Foundation (ASF) under one
008     * or more contributor license agreements.  See the NOTICE file
009     * distributed with this work for additional information
010     * regarding copyright ownership.  The ASF licenses this file
011     * to you under the Apache License, Version 2.0 (the
012     * "License"); you may not use this file except in compliance
013     * with the License.  You may obtain a copy of the License at
014     *
015     *  http://www.apache.org/licenses/LICENSE-2.0
016     *
017     * Unless required by applicable law or agreed to in writing,
018     * software distributed under the License is distributed on an
019     * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
020     * KIND, either express or implied.  See the License for the
021     * specific language governing permissions and limitations
022     * under the License.
023     */
024    
025    import java.util.ArrayList;
026    import java.util.Collections;
027    import java.util.Iterator;
028    import java.util.List;
029    
030    import com.google.common.base.Joiner;
031    
032    /**
033     * Construct a version range from a specification.
034     *
035     * @author <a href="mailto:brett@apache.org">Brett Porter</a>
036     */
037    public class VersionRange
038    {
039        private final ArtifactVersion recommendedVersion;
040    
041        private final List<Restriction> restrictions;
042    
043        private VersionRange( ArtifactVersion recommendedVersion,
044                              List<Restriction> restrictions )
045        {
046            this.recommendedVersion = recommendedVersion;
047            this.restrictions = restrictions;
048        }
049    
050        public ArtifactVersion getRecommendedVersion()
051        {
052            return recommendedVersion;
053        }
054    
055        public List<Restriction> getRestrictions()
056        {
057            return restrictions;
058        }
059    
060        public VersionRange cloneOf()
061        {
062            List<Restriction> copiedRestrictions = null;
063    
064            if ( restrictions != null )
065            {
066                copiedRestrictions = new ArrayList<Restriction>();
067    
068                if ( !restrictions.isEmpty() )
069                {
070                    copiedRestrictions.addAll( restrictions );
071                }
072            }
073    
074            return new VersionRange( recommendedVersion, copiedRestrictions );
075        }
076    
077        /**
078         * Create a version range from a string representation
079         * <p/>
080         * Some spec examples are
081         * <ul>
082         * <li><code>1.0</code> Version 1.0</li>
083         * <li><code>[1.0,2.0)</code> Versions 1.0 (included) to 2.0 (not included)</li>
084         * <li><code>[1.0,2.0]</code> Versions 1.0 to 2.0 (both included)</li>
085         * <li><code>[1.5,)</code> Versions 1.5 and higher</li>
086         * <li><code>(,1.0],[1.2,)</code> Versions up to 1.0 (included) and 1.2 or higher</li>
087         * </ul>
088         *
089         * @param spec string representation of a version or version range
090         * @return a new {@link VersionRange} object that represents the spec
091         * @throws InvalidVersionSpecificationException
092         *
093         */
094        public static VersionRange createFromVersionSpec( String spec )
095            throws InvalidVersionSpecificationException
096        {
097            if ( spec == null )
098            {
099                return null;
100            }
101    
102            List<Restriction> restrictions = new ArrayList<Restriction>();
103            String process = spec;
104            ArtifactVersion version = null;
105            ArtifactVersion upperBound = null;
106            ArtifactVersion lowerBound = null;
107    
108            while ( process.startsWith( "[" ) || process.startsWith( "(" ) )
109            {
110                int index1 = process.indexOf( ")" );
111                int index2 = process.indexOf( "]" );
112    
113                int index = index2;
114                if ( index2 < 0 || index1 < index2 )
115                {
116                    if ( index1 >= 0 )
117                    {
118                        index = index1;
119                    }
120                }
121    
122                if ( index < 0 )
123                {
124                    throw new InvalidVersionSpecificationException( "Unbounded range: " + spec );
125                }
126    
127                Restriction restriction = parseRestriction( process.substring( 0, index + 1 ) );
128                if ( lowerBound == null )
129                {
130                    lowerBound = restriction.getLowerBound();
131                }
132                if ( upperBound != null )
133                {
134                    if ( restriction.getLowerBound() == null || restriction.getLowerBound().compareTo( upperBound ) < 0 )
135                    {
136                        throw new InvalidVersionSpecificationException( "Ranges overlap: " + spec );
137                    }
138                }
139                restrictions.add( restriction );
140                upperBound = restriction.getUpperBound();
141    
142                process = process.substring( index + 1 ).trim();
143    
144                if ( process.length() > 0 && process.startsWith( "," ) )
145                {
146                    process = process.substring( 1 ).trim();
147                }
148            }
149    
150            if ( process.length() > 0 )
151            {
152                if ( restrictions.size() > 0 )
153                {
154                    throw new InvalidVersionSpecificationException(
155                        "Only fully-qualified sets allowed in multiple set scenario: " + spec );
156                }
157                else
158                {
159                    version = new DefaultArtifactVersion( process );
160                    restrictions.add( Restriction.EVERYTHING );
161                }
162            }
163    
164            return new VersionRange( version, restrictions );
165        }
166    
167        private static Restriction parseRestriction( String spec )
168            throws InvalidVersionSpecificationException
169        {
170            boolean lowerBoundInclusive = spec.startsWith( "[" );
171            boolean upperBoundInclusive = spec.endsWith( "]" );
172    
173            String process = spec.substring( 1, spec.length() - 1 ).trim();
174    
175            Restriction restriction;
176    
177            int index = process.indexOf( "," );
178    
179            if ( index < 0 )
180            {
181                if ( !lowerBoundInclusive || !upperBoundInclusive )
182                {
183                    throw new InvalidVersionSpecificationException( "Single version must be surrounded by []: " + spec );
184                }
185    
186                ArtifactVersion version = new DefaultArtifactVersion( process );
187    
188                restriction = new Restriction( version, lowerBoundInclusive, version, upperBoundInclusive );
189            }
190            else
191            {
192                String lowerBound = process.substring( 0, index ).trim();
193                String upperBound = process.substring( index + 1 ).trim();
194                if ( lowerBound.equals( upperBound ) )
195                {
196                    throw new InvalidVersionSpecificationException( "Range cannot have identical boundaries: " + spec );
197                }
198    
199                ArtifactVersion lowerVersion = null;
200                if ( lowerBound.length() > 0 )
201                {
202                    lowerVersion = new DefaultArtifactVersion( lowerBound );
203                }
204                ArtifactVersion upperVersion = null;
205                if ( upperBound.length() > 0 )
206                {
207                    upperVersion = new DefaultArtifactVersion( upperBound );
208                }
209    
210                if ( upperVersion != null && lowerVersion != null && upperVersion.compareTo( lowerVersion ) < 0 )
211                {
212                    throw new InvalidVersionSpecificationException( "Range defies version ordering: " + spec );
213                }
214    
215                restriction = new Restriction( lowerVersion, lowerBoundInclusive, upperVersion, upperBoundInclusive );
216            }
217    
218            return restriction;
219        }
220    
221        public static VersionRange createFromVersion( String version , ArtifactVersion existing)
222        {
223            List<Restriction> restrictions = Collections.emptyList();
224            if (existing == null)
225            {
226                existing = new DefaultArtifactVersion( version );
227            }
228            return new VersionRange(existing , restrictions );
229        }
230    
231        /**
232         * Creates and returns a new <code>VersionRange</code> that is a restriction of this
233         * version range and the specified version range.
234         * <p>
235         * Note: Precedence is given to the recommended version from this version range over the
236         * recommended version from the specified version range.
237         * </p>
238         *
239         * @param restriction the <code>VersionRange</code> that will be used to restrict this version
240         *                    range.
241         * @return the <code>VersionRange</code> that is a restriction of this version range and the
242         *         specified version range.
243         *         <p>
244         *         The restrictions of the returned version range will be an intersection of the restrictions
245         *         of this version range and the specified version range if both version ranges have
246         *         restrictions. Otherwise, the restrictions on the returned range will be empty.
247         *         </p>
248         *         <p>
249         *         The recommended version of the returned version range will be the recommended version of
250         *         this version range, provided that ranges falls within the intersected restrictions. If
251         *         the restrictions are empty, this version range's recommended version is used if it is not
252         *         <code>null</code>. If it is <code>null</code>, the specified version range's recommended
253         *         version is used (provided it is non-<code>null</code>). If no recommended version can be
254         *         obtained, the returned version range's recommended version is set to <code>null</code>.
255         *         </p>
256         * @throws NullPointerException if the specified <code>VersionRange</code> is
257         *                              <code>null</code>.
258         */
259        public VersionRange restrict( VersionRange restriction )
260        {
261            List<Restriction> r1 = this.restrictions;
262            List<Restriction> r2 = restriction.restrictions;
263            List<Restriction> restrictions;
264    
265            if ( r1.isEmpty() || r2.isEmpty() )
266            {
267                restrictions = Collections.emptyList();
268            }
269            else
270            {
271                restrictions = intersection( r1, r2 );
272            }
273    
274            ArtifactVersion version = null;
275            if ( restrictions.size() > 0 )
276            {
277                for ( Restriction r : restrictions )
278                {
279                    if ( recommendedVersion != null && r.containsVersion( recommendedVersion ) )
280                    {
281                        // if we find the original, use that
282                        version = recommendedVersion;
283                        break;
284                    }
285                    else if ( version == null && restriction.getRecommendedVersion() != null
286                        && r.containsVersion( restriction.getRecommendedVersion() ) )
287                    {
288                        // use this if we can, but prefer the original if possible
289                        version = restriction.getRecommendedVersion();
290                    }
291                }
292            }
293            // Either the original or the specified version ranges have no restrictions
294            else if ( recommendedVersion != null )
295            {
296                // Use the original recommended version since it exists
297                version = recommendedVersion;
298            }
299            else if ( restriction.recommendedVersion != null )
300            {
301                // Use the recommended version from the specified VersionRange since there is no
302                // original recommended version
303                version = restriction.recommendedVersion;
304            }
305    /* TODO: should throw this immediately, but need artifact
306            else
307            {
308                throw new OverConstrainedVersionException( "Restricting incompatible version ranges" );
309            }
310    */
311    
312            return new VersionRange( version, restrictions );
313        }
314    
315        private List<Restriction> intersection( List<Restriction> r1, List<Restriction> r2 )
316        {
317            List<Restriction> restrictions = new ArrayList<Restriction>( r1.size() + r2.size() );
318            Iterator<Restriction> i1 = r1.iterator();
319            Iterator<Restriction> i2 = r2.iterator();
320            Restriction res1 = i1.next();
321            Restriction res2 = i2.next();
322    
323            boolean done = false;
324            while ( !done )
325            {
326                if ( res1.getLowerBound() == null || res2.getUpperBound() == null
327                    || res1.getLowerBound().compareTo( res2.getUpperBound() ) <= 0 )
328                {
329                    if ( res1.getUpperBound() == null || res2.getLowerBound() == null
330                        || res1.getUpperBound().compareTo( res2.getLowerBound() ) >= 0 )
331                    {
332                        ArtifactVersion lower;
333                        ArtifactVersion upper;
334                        boolean lowerInclusive;
335                        boolean upperInclusive;
336    
337                        // overlaps
338                        if ( res1.getLowerBound() == null )
339                        {
340                            lower = res2.getLowerBound();
341                            lowerInclusive = res2.isLowerBoundInclusive();
342                        }
343                        else if ( res2.getLowerBound() == null )
344                        {
345                            lower = res1.getLowerBound();
346                            lowerInclusive = res1.isLowerBoundInclusive();
347                        }
348                        else
349                        {
350                            int comparison = res1.getLowerBound().compareTo( res2.getLowerBound() );
351                            if ( comparison < 0 )
352                            {
353                                lower = res2.getLowerBound();
354                                lowerInclusive = res2.isLowerBoundInclusive();
355                            }
356                            else if ( comparison == 0 )
357                            {
358                                lower = res1.getLowerBound();
359                                lowerInclusive = res1.isLowerBoundInclusive() && res2.isLowerBoundInclusive();
360                            }
361                            else
362                            {
363                                lower = res1.getLowerBound();
364                                lowerInclusive = res1.isLowerBoundInclusive();
365                            }
366                        }
367    
368                        if ( res1.getUpperBound() == null )
369                        {
370                            upper = res2.getUpperBound();
371                            upperInclusive = res2.isUpperBoundInclusive();
372                        }
373                        else if ( res2.getUpperBound() == null )
374                        {
375                            upper = res1.getUpperBound();
376                            upperInclusive = res1.isUpperBoundInclusive();
377                        }
378                        else
379                        {
380                            int comparison = res1.getUpperBound().compareTo( res2.getUpperBound() );
381                            if ( comparison < 0 )
382                            {
383                                upper = res1.getUpperBound();
384                                upperInclusive = res1.isUpperBoundInclusive();
385                            }
386                            else if ( comparison == 0 )
387                            {
388                                upper = res1.getUpperBound();
389                                upperInclusive = res1.isUpperBoundInclusive() && res2.isUpperBoundInclusive();
390                            }
391                            else
392                            {
393                                upper = res2.getUpperBound();
394                                upperInclusive = res2.isUpperBoundInclusive();
395                            }
396                        }
397    
398                        // don't add if they are equal and one is not inclusive
399                        if ( lower == null || upper == null || lower.compareTo( upper ) != 0 )
400                        {
401                            restrictions.add( new Restriction( lower, lowerInclusive, upper, upperInclusive ) );
402                        }
403                        else if ( lowerInclusive && upperInclusive )
404                        {
405                            restrictions.add( new Restriction( lower, lowerInclusive, upper, upperInclusive ) );
406                        }
407    
408                        //noinspection ObjectEquality
409                        if ( upper == res2.getUpperBound() )
410                        {
411                            // advance res2
412                            if ( i2.hasNext() )
413                            {
414                                res2 = i2.next();
415                            }
416                            else
417                            {
418                                done = true;
419                            }
420                        }
421                        else
422                        {
423                            // advance res1
424                            if ( i1.hasNext() )
425                            {
426                                res1 = i1.next();
427                            }
428                            else
429                            {
430                                done = true;
431                            }
432                        }
433                    }
434                    else
435                    {
436                        // move on to next in r1
437                        if ( i1.hasNext() )
438                        {
439                            res1 = i1.next();
440                        }
441                        else
442                        {
443                            done = true;
444                        }
445                    }
446                }
447                else
448                {
449                    // move on to next in r2
450                    if ( i2.hasNext() )
451                    {
452                        res2 = i2.next();
453                    }
454                    else
455                    {
456                        done = true;
457                    }
458                }
459            }
460    
461            return restrictions;
462        }
463    
464        public String toString()
465        {
466            if ( recommendedVersion != null )
467            {
468                return recommendedVersion.toString();
469            }
470            else
471            {
472                return Joiner.on(',').join(restrictions);
473            }
474        }
475    
476        public ArtifactVersion matchVersion( List<ArtifactVersion> versions )
477        {
478            // TODO: could be more efficient by sorting the list and then moving along the restrictions in order?
479    
480            ArtifactVersion matched = null;
481            for ( ArtifactVersion version : versions )
482            {
483                if ( containsVersion( version ) )
484                {
485                    // valid - check if it is greater than the currently matched version
486                    if ( matched == null || version.compareTo( matched ) > 0 )
487                    {
488                        matched = version;
489                    }
490                }
491            }
492            return matched;
493        }
494    
495        public boolean containsVersion( ArtifactVersion version )
496        {
497            for ( Restriction restriction : restrictions )
498            {
499                if ( restriction.containsVersion( version ) )
500                {
501                    return true;
502                }
503            }
504            return false;
505        }
506    
507        public boolean hasRestrictions()
508        {
509            return !restrictions.isEmpty() && recommendedVersion == null;
510        }
511    
512        public boolean equals( Object obj )
513        {
514            if ( this == obj )
515            {
516                return true;
517            }
518            if ( !( obj instanceof VersionRange ) )
519            {
520                return false;
521            }
522            VersionRange other = (VersionRange) obj;
523    
524            boolean equals =
525                recommendedVersion == other.recommendedVersion
526                    || ( ( recommendedVersion != null ) && recommendedVersion.equals( other.recommendedVersion ) );
527            equals &=
528                restrictions == other.restrictions
529                    || ( ( restrictions != null ) && restrictions.equals( other.restrictions ) );
530            return equals;
531        }
532    
533        public int hashCode()
534        {
535            int hash = 7;
536            hash = 31 * hash + ( recommendedVersion == null ? 0 : recommendedVersion.hashCode() );
537            hash = 31 * hash + ( restrictions == null ? 0 : restrictions.hashCode() );
538            return hash;
539        }
540    }