001    /**
002     * Copyright (c) 2000-2013 Liferay, Inc. All rights reserved.
003     *
004     * This library is free software; you can redistribute it and/or modify it under
005     * the terms of the GNU Lesser General Public License as published by the Free
006     * Software Foundation; either version 2.1 of the License, or (at your option)
007     * any later version.
008     *
009     * This library is distributed in the hope that it will be useful, but WITHOUT
010     * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
011     * FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
012     * details.
013     */
014    
015    package com.liferay.portal.kernel.util;
016    
017    import java.net.MalformedURLException;
018    import java.net.URI;
019    import java.net.URISyntaxException;
020    import java.net.URL;
021    
022    import java.util.Arrays;
023    import java.util.regex.Matcher;
024    import java.util.regex.Pattern;
025    
026    /**
027     * Provides utility methods related to data validation and format checking.
028     *
029     * @author Brian Wing Shun Chan
030     * @author Alysa Carver
031     */
032    public class Validator {
033    
034            /**
035             * Returns <code>true</code> if the booleans are equal.
036             *
037             * @param  boolean1 the first boolean
038             * @param  boolean2 the second boolean
039             * @return <code>true</code> if the booleans are equal; <code>false</code>
040             *         otherwise
041             */
042            public static boolean equals(boolean boolean1, boolean boolean2) {
043                    if (boolean1 == boolean2) {
044                            return true;
045                    }
046                    else {
047                            return false;
048                    }
049            }
050    
051            /**
052             * Returns <code>true</code> if the bytes are equal.
053             *
054             * @param  byte1 the first byte
055             * @param  byte2 the second byte
056             * @return <code>true</code> if the bytes are equal; <code>false</code>
057             *         otherwise
058             */
059            public static boolean equals(byte byte1, byte byte2) {
060                    if (byte1 == byte2) {
061                            return true;
062                    }
063                    else {
064                            return false;
065                    }
066            }
067    
068            /**
069             * Returns <code>true</code> if the characters are equal.
070             *
071             * @param  char1 the first character
072             * @param  char2 the second character
073             * @return <code>true</code> if the characters are equal; <code>false</code>
074             *         otherwise
075             */
076            public static boolean equals(char char1, char char2) {
077                    if (char1 == char2) {
078                            return true;
079                    }
080                    else {
081                            return false;
082                    }
083            }
084    
085            /**
086             * Returns <code>true</code> if the doubles are equal.
087             *
088             * @param  double1 the first double
089             * @param  double2 the second double
090             * @return <code>true</code> if the doubles are equal; <code>false</code>
091             *         otherwise
092             */
093            public static boolean equals(double double1, double double2) {
094                    if (Double.compare(double1, double2) == 0) {
095                            return true;
096                    }
097                    else {
098                            return false;
099                    }
100            }
101    
102            /**
103             * Returns <code>true</code> if the floats are equal.
104             *
105             * @param  float1 the first float
106             * @param  float2 the second float
107             * @return <code>true</code> if the floats are equal; <code>false</code>
108             *         otherwise
109             */
110            public static boolean equals(float float1, float float2) {
111                    if (Float.compare(float1, float2) == 0) {
112                            return true;
113                    }
114                    else {
115                            return false;
116                    }
117            }
118    
119            /**
120             * Returns <code>true</code> if the integers are equal.
121             *
122             * @param  int1 the first integer
123             * @param  int2 the second integer
124             * @return <code>true</code> if the integers are equal; <code>false</code>
125             *         otherwise
126             */
127            public static boolean equals(int int1, int int2) {
128                    if (int1 == int2) {
129                            return true;
130                    }
131                    else {
132                            return false;
133                    }
134            }
135    
136            /**
137             * Returns <code>true</code> if the long integers are equal.
138             *
139             * @param  long1 the first long integer
140             * @param  long2 the second long integer
141             * @return <code>true</code> if the long integers are equal;
142             *         <code>false</code> otherwise
143             */
144            public static boolean equals(long long1, long long2) {
145                    if (long1 == long2) {
146                            return true;
147                    }
148                    else {
149                            return false;
150                    }
151            }
152    
153            /**
154             * Returns <code>true</code> if the objects are either equal, the same
155             * instance, or both <code>null</code>.
156             *
157             * @param  obj1 the first object
158             * @param  obj2 the second object
159             * @return <code>true</code> if the objects are either equal, the same
160             *         instance, or both <code>null</code>; <code>false</code> otherwise
161             */
162            public static boolean equals(Object obj1, Object obj2) {
163                    if ((obj1 == null) && (obj2 == null)) {
164                            return true;
165                    }
166                    else if ((obj1 == null) || (obj2 == null)) {
167                            return false;
168                    }
169                    else {
170                            return obj1.equals(obj2);
171                    }
172            }
173    
174            /**
175             * Returns <code>true</code> if the short integers are equal.
176             *
177             * @param  short1 the first short integer
178             * @param  short2 the second short integer
179             * @return <code>true</code> if the short integers are equal;
180             *         <code>false</code> otherwise
181             */
182            public static boolean equals(short short1, short short2) {
183                    if (short1 == short2) {
184                            return true;
185                    }
186                    else {
187                            return false;
188                    }
189            }
190    
191            /**
192             * Returns <code>true</code> if the boolean arrays are equal.
193             *
194             * @param  booleanArray1 the first boolean array
195             * @param  booleanArray2 the second boolean array
196             * @return <code>true</code> if the booleans arrays are equal; <code>false
197             *         </code>otherwise
198             */
199            public static boolean equalsSorted(
200                    boolean[] booleanArray1, boolean[] booleanArray2) {
201    
202                    Boolean[] booleanObjArray1 = ArrayUtil.toArray(booleanArray1);
203    
204                    Arrays.sort(booleanObjArray1);
205    
206                    Boolean[] booleanObjArray2 = ArrayUtil.toArray(booleanArray2);
207    
208                    Arrays.sort(booleanObjArray2);
209    
210                    return Arrays.equals(booleanObjArray1, booleanObjArray2);
211            }
212    
213            /**
214             * Returns <code>true</code> if the byte arrays are equal.
215             *
216             * @param  byteArray1 the first byte array
217             * @param  byteArray2 the second byte array
218             * @return <code>true</code> if the byte arrays are equal; <code>false
219             *         </code>otherwise
220             */
221            public static boolean equalsSorted(byte[] byteArray1, byte[] byteArray2) {
222                    byteArray1 = ArrayUtil.clone(byteArray1);
223    
224                    Arrays.sort(byteArray1);
225    
226                    byteArray2 = ArrayUtil.clone(byteArray2);
227    
228                    Arrays.sort(byteArray2);
229    
230                    return Arrays.equals(byteArray1, byteArray2);
231            }
232    
233            /**
234             * Returns <code>true</code> if the char arrays are equal.
235             *
236             * @param  charArray1 the first char array
237             * @param  charArray2 the second char array
238             * @return <code>true</code> if the char arrays are equal; <code>false
239             *         </code>otherwise
240             */
241            public static boolean equalsSorted(char[] charArray1, char[] charArray2) {
242                    charArray1 = ArrayUtil.clone(charArray1);
243    
244                    Arrays.sort(charArray1);
245    
246                    charArray2 = ArrayUtil.clone(charArray2);
247    
248                    Arrays.sort(charArray2);
249    
250                    return Arrays.equals(charArray1, charArray2);
251            }
252    
253            /**
254             * Returns <code>true</code> if the double arrays are equal.
255             *
256             * @param  doubleArray1 the first double array
257             * @param  doubleArray2 the second double array
258             * @return <code>true</code> if the double arrays are equal; <code>false
259             *         </code>otherwise
260             */
261            public static boolean equalsSorted(
262                    double[] doubleArray1, double[] doubleArray2) {
263    
264                    doubleArray1 = ArrayUtil.clone(doubleArray1);
265    
266                    Arrays.sort(doubleArray1);
267    
268                    doubleArray2 = ArrayUtil.clone(doubleArray2);
269    
270                    Arrays.sort(doubleArray2);
271    
272                    return Arrays.equals(doubleArray1, doubleArray2);
273            }
274    
275            /**
276             * Returns <code>true</code> if the float arrays are equal.
277             *
278             * @param  floatArray1 the first float array
279             * @param  floatArray2 the second char array
280             * @return <code>true</code> if the float arrays are equal; <code>false
281             *         </code>otherwise
282             */
283            public static boolean equalsSorted(
284                    float[] floatArray1, float[] floatArray2) {
285    
286                    floatArray1 = ArrayUtil.clone(floatArray1);
287    
288                    Arrays.sort(floatArray1);
289    
290                    floatArray2 = ArrayUtil.clone(floatArray2);
291    
292                    Arrays.sort(floatArray2);
293    
294                    return Arrays.equals(floatArray1, floatArray2);
295            }
296    
297            /**
298             * Returns <code>true</code> if the int arrays are equal.
299             *
300             * @param  intArray1 the first int array
301             * @param  intArray2 the second int array
302             * @return <code>true</code> if the int arrays are equal; <code>false</code>
303             *         otherwise
304             */
305            public static boolean equalsSorted(int[] intArray1, int[] intArray2) {
306                    intArray1 = ArrayUtil.clone(intArray1);
307    
308                    Arrays.sort(intArray1);
309    
310                    intArray2 = ArrayUtil.clone(intArray2);
311    
312                    Arrays.sort(intArray2);
313    
314                    return Arrays.equals(intArray1, intArray2);
315            }
316    
317            /**
318             * Returns <code>true</code> if the long arrays are equal.
319             *
320             * @param  longArray1 the first long array
321             * @param  longArray2 the second long array
322             * @return <code>true</code> if the long arrays are equal; <code>false
323             *         </code>otherwise
324             */
325            public static boolean equalsSorted(long[] longArray1, long[] longArray2) {
326                    longArray1 = ArrayUtil.clone(longArray1);
327    
328                    Arrays.sort(longArray1);
329    
330                    longArray2 = ArrayUtil.clone(longArray2);
331    
332                    Arrays.sort(longArray2);
333    
334                    return Arrays.equals(longArray1, longArray2);
335            }
336    
337            /**
338             * Returns <code>true</code> if the object arrays are equal.
339             *
340             * @param  objArray1 the first object array
341             * @param  objArray2 the second object array
342             * @return <code>true</code> if the object arrays are equal; <code>false
343             *         </code>otherwise
344             */
345            public static boolean equalsSorted(Object[] objArray1, Object[] objArray2) {
346                    objArray1 = ArrayUtil.clone(objArray1);
347    
348                    Arrays.sort(objArray1);
349    
350                    objArray2 = ArrayUtil.clone(objArray2);
351    
352                    Arrays.sort(objArray2);
353    
354                    return Arrays.equals(objArray1, objArray2);
355            }
356    
357            /**
358             * Returns <code>true</code> if the short arrays are equal.
359             *
360             * @param  shortArray1 the first short array
361             * @param  shortArray2 the second short array
362             * @return <code>true</code> if the short arrays are equal; <code>false
363             *         </code>otherwise
364             */
365            public static boolean equalsSorted(
366                    short[] shortArray1, short[] shortArray2) {
367    
368                    shortArray1 = ArrayUtil.clone(shortArray1);
369    
370                    Arrays.sort(shortArray1);
371    
372                    shortArray2 = ArrayUtil.clone(shortArray2);
373    
374                    Arrays.sort(shortArray2);
375    
376                    return Arrays.equals(shortArray1, shortArray2);
377            }
378    
379            /**
380             * Returns <code>true</code> if the string is an email address. The only
381             * requirements are that the string consist of two parts separated by an @
382             * symbol, and that it contain no whitespace.
383             *
384             * @param  address the string to check
385             * @return <code>true</code> if the string is an email address;
386             *         <code>false</code> otherwise
387             */
388            public static boolean isAddress(String address) {
389                    if (isNull(address)) {
390                            return false;
391                    }
392    
393                    String[] tokens = address.split(StringPool.AT);
394    
395                    if (tokens.length != 2) {
396                            return false;
397                    }
398    
399                    for (String token : tokens) {
400                            for (char c : token.toCharArray()) {
401                                    if (Character.isWhitespace(c)) {
402                                            return false;
403                                    }
404                            }
405                    }
406    
407                    return true;
408            }
409    
410            /**
411             * Returns <code>true</code> if the string is an alphanumeric name, meaning
412             * it contains nothing but English letters, numbers, and spaces.
413             *
414             * @param  name the string to check
415             * @return <code>true</code> if the string is an Alphanumeric name;
416             *         <code>false</code> otherwise
417             */
418            public static boolean isAlphanumericName(String name) {
419                    if (isNull(name)) {
420                            return false;
421                    }
422    
423                    for (char c : name.trim().toCharArray()) {
424                            if (!isChar(c) && !isDigit(c) && !Character.isWhitespace(c)) {
425                                    return false;
426                            }
427                    }
428    
429                    return true;
430            }
431    
432            /**
433             * Returns <code>true</code> if the character is in the ASCII character set.
434             * This includes characters with integer values between 32 and 126
435             * (inclusive).
436             *
437             * @param  c the character to check
438             * @return <code>true</code> if the character is in the ASCII character set;
439             *         <code>false</code> otherwise
440             */
441            public static boolean isAscii(char c) {
442                    int i = c;
443    
444                    if ((i >= 32) && (i <= 126)) {
445                            return true;
446                    }
447                    else {
448                            return false;
449                    }
450            }
451    
452            public static boolean isBlank(String s) {
453                    if (s == null) {
454                            return true;
455                    }
456    
457                    if (s.length() == 0) {
458                            return true;
459                    }
460    
461                    return false;
462            }
463    
464            /**
465             * Returns <code>true</code> if the character is an upper or lower case
466             * English letter.
467             *
468             * @param  c the character to check
469             * @return <code>true</code> if the character is an upper or lower case
470             *         English letter; <code>false</code> otherwise
471             */
472            public static boolean isChar(char c) {
473                    int x = c;
474    
475                    if (((x >= _CHAR_LOWER_CASE_BEGIN) && (x <= _CHAR_LOWER_CASE_END)) ||
476                            ((x >= _CHAR_UPPER_CASE_BEGIN) && (x <= _CHAR_UPPER_CASE_END))) {
477    
478                            return true;
479                    }
480    
481                    return false;
482            }
483    
484            /**
485             * Returns <code>true</code> if string consists only of upper and lower case
486             * English letters.
487             *
488             * @param  s the string to check
489             * @return <code>true</code> if the string consists only of upper and lower
490             *         case English letters
491             */
492            public static boolean isChar(String s) {
493                    if (isNull(s)) {
494                            return false;
495                    }
496    
497                    for (char c : s.toCharArray()) {
498                            if (!isChar(c)) {
499                                    return false;
500                            }
501                    }
502    
503                    return true;
504            }
505    
506            /**
507             * Returns <code>true</code> if the date is valid in the Gregorian calendar.
508             *
509             * @param  month the month to check
510             * @param  day the day to check
511             * @param  year the year to check
512             * @return <code>true</code> if the date is valid in the Gregorian calendar;
513             *         <code>false</code> otherwise
514             */
515            public static boolean isDate(int month, int day, int year) {
516                    return isGregorianDate(month, day, year);
517            }
518    
519            /**
520             * Returns <code>true</code> if the character is a digit between 0 and 9
521             * (inclusive).
522             *
523             * @param  c the character to check
524             * @return <code>true</code> if the character is a digit between 0 and 9
525             *         (inclusive); <code>false</code> otherwise
526             */
527            public static boolean isDigit(char c) {
528                    int x = c;
529    
530                    if ((x >= _DIGIT_BEGIN) && (x <= _DIGIT_END)) {
531                            return true;
532                    }
533    
534                    return false;
535            }
536    
537            /**
538             * Returns <code>true</code> if the string consists of only digits between 0
539             * and 9 (inclusive).
540             *
541             * @param  s the string to check
542             * @return <code>true</code> if the string consists of only digits between 0
543             *         and 9 (inclusive); <code>false</code> otherwise
544             */
545            public static boolean isDigit(String s) {
546                    if (isNull(s)) {
547                            return false;
548                    }
549    
550                    for (char c : s.toCharArray()) {
551                            if (!isDigit(c)) {
552                                    return false;
553                            }
554                    }
555    
556                    return true;
557            }
558    
559            /**
560             * Returns <code>true</code> if the string is a valid domain name. See
561             * RFC-1034 (section 3), RFC-1123 (section 2.1), and RFC-952 (section B.
562             * Lexical grammar).
563             *
564             * @param  domainName the string to check
565             * @return <code>true</code> if the string is a valid domain name;
566             *         <code>false</code> otherwise
567             */
568            public static boolean isDomain(String domainName) {
569    
570                    // See RFC-1034 (section 3), RFC-1123 (section 2.1), and RFC-952
571                    // (section B. Lexical grammar)
572    
573                    if (isNull(domainName)) {
574                            return false;
575                    }
576    
577                    if (domainName.length() > 255) {
578                            return false;
579                    }
580    
581                    if (domainName.startsWith(StringPool.PERIOD)) {
582                            return false;
583                    }
584    
585                    String[] domainNameArray = StringUtil.split(
586                            domainName, CharPool.PERIOD);
587    
588                    for (String domainNamePart : domainNameArray) {
589                            char[] domainNamePartCharArray = domainNamePart.toCharArray();
590    
591                            for (int i = 0; i < domainNamePartCharArray.length; i++) {
592                                    char c = domainNamePartCharArray[i];
593    
594                                    if ((i == 0) && (c == CharPool.DASH)) {
595                                            return false;
596                                    }
597    
598                                    if ((i == (domainNamePartCharArray.length - 1)) &&
599                                            (c == CharPool.DASH)) {
600    
601                                            return false;
602                                    }
603    
604                                    if (!isChar(c) && !isDigit(c) && (c != CharPool.DASH)) {
605                                            return false;
606                                    }
607                            }
608                    }
609    
610                    return true;
611            }
612    
613            /**
614             * Returns <code>true</code> if the string is a valid email address.
615             *
616             * @param  emailAddress the string to check
617             * @return <code>true</code> if the string is a valid email address;
618             *         <code>false</code> otherwise
619             */
620            public static boolean isEmailAddress(String emailAddress) {
621                    Matcher matcher = _emailAddressPattern.matcher(emailAddress);
622    
623                    return matcher.matches();
624            }
625    
626            /**
627             * Returns <code>true</code> if the character is a special character in an
628             * email address.
629             *
630             * @param  c the character to check
631             * @return <code>true</code> if the character is a special character in an
632             *         email address; <code>false</code> otherwise
633             */
634            public static boolean isEmailAddressSpecialChar(char c) {
635    
636                    // LEP-1445
637    
638                    for (char specialChar : _EMAIL_ADDRESS_SPECIAL_CHAR) {
639                            if (c == specialChar) {
640                                    return true;
641                            }
642                    }
643    
644                    return false;
645            }
646    
647            /**
648             * Returns <code>true</code> if the file extension is valid.
649             *
650             * @param  fileExtension string to check
651             * @return <code>true</code> if the extension is valid; <code>false</code>
652             *         otherwise
653             */
654            public static boolean isFileExtension(String fileExtension) {
655                    if (isNull(fileExtension) ||
656                            fileExtension.contains(StringPool.BACK_SLASH) ||
657                            fileExtension.contains(StringPool.NULL_CHAR) ||
658                            fileExtension.contains(StringPool.SLASH)) {
659    
660                            return false;
661                    }
662    
663                    return true;
664            }
665    
666            public static boolean isFileName(String name) {
667                    if (isNull(name) || name.equals(StringPool.PERIOD) ||
668                            name.equals(StringPool.DOUBLE_PERIOD) ||
669                            name.contains(StringPool.BACK_SLASH) ||
670                            name.contains(StringPool.NULL_CHAR) ||
671                            name.contains(StringPool.SLASH)) {
672    
673                            return false;
674                    }
675    
676                    return true;
677            }
678    
679            public static boolean isFilePath(String path, boolean isParentDirAllowed) {
680                    if (isNull(path)) {
681                            return false;
682                    }
683    
684                    if (path.contains(StringPool.NULL_CHAR)) {
685                            return false;
686                    }
687    
688                    if (isParentDirAllowed) {
689                            return true;
690                    }
691    
692                    if (path.equals(StringPool.DOUBLE_PERIOD)) {
693                            return false;
694                    }
695    
696                    String normalizedPath = path.replace(
697                            CharPool.BACK_SLASH, CharPool.SLASH);
698    
699                    if (normalizedPath.startsWith(
700                                    StringPool.DOUBLE_PERIOD.concat(StringPool.SLASH))) {
701    
702                            return false;
703                    }
704    
705                    if (normalizedPath.endsWith(
706                                    StringPool.SLASH.concat(StringPool.DOUBLE_PERIOD))) {
707    
708                            return false;
709                    }
710    
711                    if (normalizedPath.contains(
712                                    StringPool.SLASH.concat(
713                                            StringPool.DOUBLE_PERIOD).concat(StringPool.SLASH))) {
714    
715                            return false;
716                    }
717    
718                    return true;
719            }
720    
721            /**
722             * Returns <code>true</code> if the date is valid in the Gregorian calendar.
723             *
724             * @param  month the month (0-based, meaning 0 for January)
725             * @param  day the day of the month
726             * @param  year the year
727             * @return <code>true</code> if the date is valid; <code>false</code>
728             *         otherwise
729             */
730            public static boolean isGregorianDate(int month, int day, int year) {
731                    if ((month < 0) || (month > 11)) {
732                            return false;
733                    }
734    
735                    int[] months = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
736    
737                    if (month == 1) {
738                            int febMax = 28;
739    
740                            if (((year % 4) == 0) && ((year % 100) != 0) ||
741                                    ((year % 400) == 0)) {
742    
743                                    febMax = 29;
744                            }
745    
746                            if ((day < 1) || (day > febMax)) {
747                                    return false;
748                            }
749                    }
750                    else if ((day < 1) || (day > months[month])) {
751                            return false;
752                    }
753    
754                    return true;
755            }
756    
757            /**
758             * Returns <code>true</code> if the string is a hexidecimal number. At
759             * present the only requirement is that the string is not <code>null</code>;
760             * it does not actually check the format of the string.
761             *
762             * @param  s the string to check
763             * @return <code>true</code> if the string is a hexidecimal number;
764             *         <code>false</code> otherwise
765             * @see    #isNull(String)
766             */
767            public static boolean isHex(String s) {
768                    if (isNull(s)) {
769                            return false;
770                    }
771    
772                    return true;
773            }
774    
775            /**
776             * Returns <code>true</code> if the string is a valid host name.
777             *
778             * @param  name the string to check
779             * @return <code>true</code> if the string is a valid host name;
780             *         <code>false</code> otherwise
781             */
782            public static boolean isHostName(String name) {
783                    if (isNull(name)) {
784                            return false;
785                    }
786    
787                    char[] nameCharArray = name.toCharArray();
788    
789                    if ((nameCharArray[0] == CharPool.DASH) ||
790                            (nameCharArray[0] == CharPool.PERIOD) ||
791                            (nameCharArray[nameCharArray.length - 1] == CharPool.DASH)) {
792    
793                            return false;
794                    }
795    
796                    for (char c : nameCharArray) {
797                            if (!isChar(c) && !isDigit(c) && (c != CharPool.CLOSE_BRACKET) &&
798                                    (c != CharPool.COLON) && (c != CharPool.DASH) &&
799                                    (c != CharPool.OPEN_BRACKET) && (c != CharPool.PERIOD)) {
800    
801                                    return false;
802                            }
803                    }
804    
805                    return true;
806            }
807    
808            /**
809             * Returns <code>true</code> if the string is an HTML document. The only
810             * requirement is that it contain the opening and closing html tags.
811             *
812             * @param  s the string to check
813             * @return <code>true</code> if the string is an HTML document;
814             *         <code>false</code> otherwise
815             */
816            public static boolean isHTML(String s) {
817                    if (isNull(s)) {
818                            return false;
819                    }
820    
821                    if ((s.contains("<html>") || s.contains("<HTML>")) &&
822                            (s.contains("</html>") || s.contains("</HTML>"))) {
823    
824                            return true;
825                    }
826    
827                    return false;
828            }
829    
830            /**
831             * Returns <code>true</code> if the string is a valid IPv4 or IPv6 IP
832             * address.
833             *
834             * @param  ipAddress the string to check
835             * @return <code>true</code> if the string is a valid IPv4 or IPv6 IP
836             *         address; <code>false</code> otherwise
837             */
838            public static boolean isIPAddress(String ipAddress) {
839                    if (isIPv4Address(ipAddress) || isIPv6Address(ipAddress)) {
840                            return true;
841                    }
842    
843                    return false;
844            }
845    
846            /**
847             * Returns <code>true</code> if the string is a valid IPv4 IP address.
848             *
849             * @param  ipAddress the string to check
850             * @return <code>true</code> if the string is a valid IPv4 IP address;
851             *         <code>false</code> otherwise
852             */
853            public static boolean isIPv4Address(String ipAddress) {
854                    Matcher matcher = _ipv4AddressPattern.matcher(ipAddress);
855    
856                    return matcher.matches();
857            }
858    
859            /**
860             * Returns <code>true</code> if the string is a valid IPv6 IP address.
861             *
862             * @param  ipAddress the string to check
863             * @return <code>true</code> if the string is a valid IPv6 IP address;
864             *         <code>false</code> otherwise
865             */
866            public static boolean isIPv6Address(String ipAddress) {
867                    if (isNull(ipAddress)) {
868                            return false;
869                    }
870    
871                    if (StringUtil.startsWith(ipAddress, CharPool.OPEN_BRACKET) &&
872                            StringUtil.endsWith(ipAddress, CharPool.CLOSE_BRACKET)) {
873    
874                            ipAddress = ipAddress.substring(1, ipAddress.length() - 1);
875                    }
876    
877                    Matcher matcher = _ipv6AddressPattern.matcher(ipAddress);
878    
879                    return matcher.matches();
880            }
881    
882            /**
883             * Returns <code>true</code> if the date is valid in the Julian calendar.
884             *
885             * @param  month the month (0-based, meaning 0 for January)
886             * @param  day the day of the month
887             * @param  year the year
888             * @return <code>true</code> if the date is valid in the Julian calendar;
889             *         <code>false</code> otherwise
890             */
891            public static boolean isJulianDate(int month, int day, int year) {
892                    if ((month < 0) || (month > 11)) {
893                            return false;
894                    }
895    
896                    int[] months = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
897    
898                    if (month == 1) {
899                            int febMax = 28;
900    
901                            if ((year % 4) == 0) {
902                                    febMax = 29;
903                            }
904    
905                            if ((day < 1) || (day > febMax)) {
906                                    return false;
907                            }
908                    }
909                    else if ((day < 1) || (day > months[month])) {
910                            return false;
911                    }
912    
913                    return true;
914            }
915    
916            /**
917             * Returns <code>true</code> if the string contains a valid number according
918             * to the Luhn algorithm, commonly used to validate credit card numbers.
919             *
920             * @param  number the string to check
921             * @return <code>true</code> if the string contains a valid number according
922             *         to the Luhn algorithm; <code>false</code> otherwise
923             */
924            public static boolean isLUHN(String number) {
925                    if (number == null) {
926                            return false;
927                    }
928    
929                    number = StringUtil.reverse(number);
930    
931                    int total = 0;
932    
933                    for (int i = 0; i < number.length(); i++) {
934                            int x = 0;
935    
936                            if (((i + 1) % 2) == 0) {
937                                    x = GetterUtil.getInteger(number.substring(i, i + 1)) * 2;
938    
939                                    if (x >= 10) {
940                                            String s = String.valueOf(x);
941    
942                                            x =
943                                                    GetterUtil.getInteger(s.substring(0, 1)) +
944                                                            GetterUtil.getInteger(s.substring(1, 2));
945                                    }
946                            }
947                            else {
948                                    x = GetterUtil.getInteger(number.substring(i, i + 1));
949                            }
950    
951                            total = total + x;
952                    }
953    
954                    if ((total % 10) == 0) {
955                            return true;
956                    }
957                    else {
958                            return false;
959                    }
960            }
961    
962            /**
963             * Returns <code>true</code> if the string is a name, meaning it contains
964             * nothing but English letters and spaces.
965             *
966             * @param  name the string to check
967             * @return <code>true</code> if the string is a name; <code>false</code>
968             *         otherwise
969             */
970            public static boolean isName(String name) {
971                    if (isNull(name)) {
972                            return false;
973                    }
974    
975                    for (char c : name.trim().toCharArray()) {
976                            if (!isChar(c) && !Character.isWhitespace(c)) {
977                                    return false;
978                            }
979                    }
980    
981                    return true;
982            }
983    
984            /**
985             * Returns <code>true</code> if the long number object is not
986             * <code>null</code>, meaning it is neither a <code>null</code> reference or
987             * zero.
988             *
989             * @param  l the long number object to check
990             * @return <code>true</code> if the long number object is not
991             *         <code>null</code>; <code>false</code> otherwise
992             */
993            public static boolean isNotNull(Long l) {
994                    return !isNull(l);
995            }
996    
997            /**
998             * Returns <code>true</code> if the object is not <code>null</code>, using
999             * the rules from {@link #isNotNull(Long)} or {@link #isNotNull(String)} if
1000             * the object is one of these types.
1001             *
1002             * @param  obj the object to check
1003             * @return <code>true</code> if the object is not <code>null</code>;
1004             *         <code>false</code> otherwise
1005             */
1006            public static boolean isNotNull(Object obj) {
1007                    return !isNull(obj);
1008            }
1009    
1010            /**
1011             * Returns <code>true</code> if the array is not <code>null</code>, meaning
1012             * it is neither a <code>null</code> reference or empty.
1013             *
1014             * @param  array the array to check
1015             * @return <code>true</code> if the array is not <code>null</code>;
1016             *         <code>false</code> otherwise
1017             */
1018            public static boolean isNotNull(Object[] array) {
1019                    return !isNull(array);
1020            }
1021    
1022            /**
1023             * Returns <code>true</code> if the string is not <code>null</code>, meaning
1024             * it is not a <code>null</code> reference, nothing but spaces, or the
1025             * string "<code>null</code>".
1026             *
1027             * @param  s the string to check
1028             * @return <code>true</code> if the string is not <code>null</code>;
1029             *         <code>false</code> otherwise
1030             */
1031            public static boolean isNotNull(String s) {
1032                    return !isNull(s);
1033            }
1034    
1035            /**
1036             * Returns <code>true</code> if the long number object is <code>null</code>,
1037             * meaning it is either a <code>null</code> reference or zero.
1038             *
1039             * @param  l the long number object to check
1040             * @return <code>true</code> if the long number object is <code>null</code>;
1041             *         <code>false</code> otherwise
1042             */
1043            public static boolean isNull(Long l) {
1044                    if ((l == null) || (l.longValue() == 0)) {
1045                            return true;
1046                    }
1047                    else {
1048                            return false;
1049                    }
1050            }
1051    
1052            /**
1053             * Returns <code>true</code> if the object is <code>null</code>, using the
1054             * rules from {@link #isNull(Long)} or {@link #isNull(String)} if the object
1055             * is one of these types.
1056             *
1057             * @param  obj the object to check
1058             * @return <code>true</code> if the object is <code>null</code>;
1059             *         <code>false</code> otherwise
1060             */
1061            public static boolean isNull(Object obj) {
1062                    if (obj instanceof Long) {
1063                            return isNull((Long)obj);
1064                    }
1065                    else if (obj instanceof String) {
1066                            return isNull((String)obj);
1067                    }
1068                    else if (obj == null) {
1069                            return true;
1070                    }
1071                    else {
1072                            return false;
1073                    }
1074            }
1075    
1076            /**
1077             * Returns <code>true</code> if the array is <code>null</code>, meaning it
1078             * is either a <code>null</code> reference or empty.
1079             *
1080             * @param  array the array to check
1081             * @return <code>true</code> if the array is <code>null</code>;
1082             *         <code>false</code> otherwise
1083             */
1084            public static boolean isNull(Object[] array) {
1085                    if ((array == null) || (array.length == 0)) {
1086                            return true;
1087                    }
1088                    else {
1089                            return false;
1090                    }
1091            }
1092    
1093            /**
1094             * Returns <code>true</code> if the string is <code>null</code>, meaning it
1095             * is a <code>null</code> reference, nothing but spaces, or the string
1096             * "<code>null</code>".
1097             *
1098             * @param  s the string to check
1099             * @return <code>true</code> if the string is <code>null</code>;
1100             *         <code>false</code> otherwise
1101             */
1102            public static boolean isNull(String s) {
1103                    if (s == null) {
1104                            return true;
1105                    }
1106    
1107                    int counter = 0;
1108    
1109                    for (int i = 0; i < s.length(); i++) {
1110                            char c = s.charAt(i);
1111    
1112                            if (c == CharPool.SPACE) {
1113                                    continue;
1114                            }
1115                            else if (counter > 3) {
1116                                    return false;
1117                            }
1118    
1119                            if (counter == 0) {
1120                                    if (c != CharPool.LOWER_CASE_N) {
1121                                            return false;
1122                                    }
1123                            }
1124                            else if (counter == 1) {
1125                                    if (c != CharPool.LOWER_CASE_U) {
1126                                            return false;
1127                                    }
1128                            }
1129                            else if ((counter == 2) || (counter == 3)) {
1130                                    if (c != CharPool.LOWER_CASE_L) {
1131                                            return false;
1132                                    }
1133                            }
1134    
1135                            counter++;
1136                    }
1137    
1138                    if ((counter == 0) || (counter == 4)) {
1139                            return true;
1140                    }
1141    
1142                    return false;
1143            }
1144    
1145            /**
1146             * Returns <code>true</code> if the string is a decimal integer number,
1147             * meaning it contains nothing but decimal digits.
1148             *
1149             * @param  number the string to check
1150             * @return <code>true</code> if the string is a decimal integer number;
1151             *         <code>false</code> otherwise
1152             */
1153            public static boolean isNumber(String number) {
1154                    if (isNull(number)) {
1155                            return false;
1156                    }
1157    
1158                    for (char c : number.toCharArray()) {
1159                            if (!isDigit(c)) {
1160                                    return false;
1161                            }
1162                    }
1163    
1164                    return true;
1165            }
1166    
1167            /**
1168             * Returns <code>true</code> if the string is a valid password, meaning it
1169             * is at least four characters long and contains only letters and decimal
1170             * digits.
1171             *
1172             * @param  password the string to check
1173             * @return <code>true</code> if the string is a valid password;
1174             *         <code>false</code> otherwise
1175             */
1176            public static boolean isPassword(String password) {
1177                    if (isNull(password)) {
1178                            return false;
1179                    }
1180    
1181                    if (password.length() < 4) {
1182                            return false;
1183                    }
1184    
1185                    for (char c : password.toCharArray()) {
1186                            if (!isChar(c) && !isDigit(c)) {
1187                                    return false;
1188                            }
1189                    }
1190    
1191                    return true;
1192            }
1193    
1194            /**
1195             * Returns <code>true</code> if the string is a valid phone number. The only
1196             * requirement is that there are decimal digits in the string; length and
1197             * format are not checked.
1198             *
1199             * @param  phoneNumber the string to check
1200             * @return <code>true</code> if the string is a valid phone number;
1201             *         <code>false</code> otherwise
1202             */
1203            public static boolean isPhoneNumber(String phoneNumber) {
1204                    return isNumber(StringUtil.extractDigits(phoneNumber));
1205            }
1206    
1207            public static boolean isUri(String uri) {
1208                    if (isNotNull(uri)) {
1209                            try {
1210                                    new URI(uri);
1211    
1212                                    return true;
1213                            }
1214                            catch (URISyntaxException urise) {
1215                            }
1216                    }
1217    
1218                    return false;
1219            }
1220    
1221            /**
1222             * Returns <code>true</code> if the string is a valid URL based on the rules
1223             * in {@link java.net.URL}.
1224             *
1225             * @param  url the string to check
1226             * @return <code>true</code> if the string is a valid URL;
1227             *         <code>false</code> otherwise
1228             */
1229            public static boolean isUrl(String url) {
1230                    if (isNotNull(url)) {
1231                            if (url.indexOf(CharPool.COLON) == -1) {
1232                                    return false;
1233                            }
1234    
1235                            try {
1236                                    new URL(url);
1237    
1238                                    return true;
1239                            }
1240                            catch (MalformedURLException murle) {
1241                            }
1242                    }
1243    
1244                    return false;
1245            }
1246    
1247            /**
1248             * Returns <code>true</code> if the string is a valid variable name in Java.
1249             *
1250             * @param  variableName the string to check
1251             * @return <code>true</code> if the string is a valid variable name in Java;
1252             *         <code>false</code> otherwise
1253             */
1254            public static boolean isVariableName(String variableName) {
1255                    if (isNull(variableName)) {
1256                            return false;
1257                    }
1258    
1259                    Matcher matcher = _variableNamePattern.matcher(variableName);
1260    
1261                    if (matcher.matches()) {
1262                            return true;
1263                    }
1264                    else {
1265                            return false;
1266                    }
1267            }
1268    
1269            /**
1270             * Returns <code>true</code> if the string is a valid variable term, meaning
1271             * it begins with "[$" and ends with "$]".
1272             *
1273             * @param  s the string to check
1274             * @return <code>true</code> if the string is a valid variable term;
1275             *         <code>false</code> otherwise
1276             */
1277            public static boolean isVariableTerm(String s) {
1278                    if (s.startsWith(_VARIABLE_TERM_BEGIN) &&
1279                            s.endsWith(_VARIABLE_TERM_END)) {
1280    
1281                            return true;
1282                    }
1283                    else {
1284                            return false;
1285                    }
1286            }
1287    
1288            /**
1289             * Returns <code>true</code> if the character is whitespace, meaning it is
1290             * either the <code>null</code> character '0' or whitespace according to
1291             * {@link java.lang.Character#isWhitespace(char)}.
1292             *
1293             * @param  c the character to check
1294             * @return <code>true</code> if the character is whitespace;
1295             *         <code>false</code> otherwise
1296             */
1297            public static boolean isWhitespace(char c) {
1298                    int i = c;
1299    
1300                    if ((i == 0) || Character.isWhitespace(c)) {
1301                            return true;
1302                    }
1303                    else {
1304                            return false;
1305                    }
1306            }
1307    
1308            /**
1309             * Returns <code>true</code> if the string is an XML document. The only
1310             * requirement is that it contain either the xml start tag "<?xml" or the
1311             * empty document tag "<root />".
1312             *
1313             * @param  s the string to check
1314             * @return <code>true</code> if the string is an XML document;
1315             *         <code>false</code> otherwise
1316             */
1317            public static boolean isXml(String s) {
1318                    if (s.startsWith(_XML_BEGIN) || s.startsWith(_XML_EMPTY)) {
1319                            return true;
1320                    }
1321                    else {
1322                            return false;
1323                    }
1324            }
1325    
1326            private static final int _CHAR_LOWER_CASE_BEGIN = 97;
1327    
1328            private static final int _CHAR_LOWER_CASE_END = 122;
1329    
1330            private static final int _CHAR_UPPER_CASE_BEGIN = 65;
1331    
1332            private static final int _CHAR_UPPER_CASE_END = 90;
1333    
1334            private static final int _DIGIT_BEGIN = 48;
1335    
1336            private static final int _DIGIT_END = 57;
1337    
1338            private static final char[] _EMAIL_ADDRESS_SPECIAL_CHAR = new char[] {
1339                    '.', '!', '#', '$', '%', '&', '\'', '*', '+', '-', '/', '=', '?', '^',
1340                    '_', '`', '{', '|', '}', '~'
1341            };
1342    
1343            private static final String _VARIABLE_TERM_BEGIN = "[$";
1344    
1345            private static final String _VARIABLE_TERM_END = "$]";
1346    
1347            private static final String _XML_BEGIN = "<?xml";
1348    
1349            private static final String _XML_EMPTY = "<root />";
1350    
1351            private static Pattern _emailAddressPattern = Pattern.compile(
1352                    "[\\w!#$%&'*+/=?^_`{|}~-]+(?:\\.[\\w!#$%&'*+/=?^_`{|}~-]+)*@" +
1353                    "(?:[\\w](?:[\\w-]*[\\w])?\\.)+[\\w](?:[\\w-]*[\\w])?");
1354            private static Pattern _ipv4AddressPattern = Pattern.compile(
1355                    "^" +
1356                    "(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\\." +
1357                    "(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\\." +
1358                    "(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\\." +
1359                    "(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)" +
1360                    "$");
1361            private static Pattern _ipv6AddressPattern = Pattern.compile(
1362                    "^" +
1363                    "\\s*((([0-9A-Fa-f]{1,4}:){7}([0-9A-Fa-f]{1,4}|:))|" +
1364                    "(([0-9A-Fa-f]{1,4}:){6}(:[0-9A-Fa-f]{1,4}|" +
1365                    "((25[0-5]|2[0-4]\\d|1\\d\\d|[1-9]?\\d)" +
1366                    "(\\.(25[0-5]|2[0-4]\\d|1\\d\\d|[1-9]?\\d)){3})|:))|" +
1367                    "(([0-9A-Fa-f]{1,4}:){5}(((:[0-9A-Fa-f]{1,4}){1,2})|:" +
1368                    "((25[0-5]|2[0-4]\\d|1\\d\\d|[1-9]?\\d)" +
1369                    "(\\.(25[0-5]|2[0-4]\\d|1\\d\\d|[1-9]?\\d)){3})|:))|" +
1370                    "(([0-9A-Fa-f]{1,4}:){4}(((:[0-9A-Fa-f]{1,4}){1,3})|" +
1371                    "((:[0-9A-Fa-f]{1,4})?:((25[0-5]|2[0-4]\\d|1\\d\\d|[1-9]?\\d)" +
1372                    "(\\.(25[0-5]|2[0-4]\\d|1\\d\\d|[1-9]?\\d)){3}))|:))|" +
1373                    "(([0-9A-Fa-f]{1,4}:){3}(((:[0-9A-Fa-f]{1,4}){1,4})|" +
1374                    "((:[0-9A-Fa-f]{1,4}){0,2}:((25[0-5]|2[0-4]\\d|1\\d\\d|[1-9]?\\d)" +
1375                    "(\\.(25[0-5]|2[0-4]\\d|1\\d\\d|[1-9]?\\d)){3}))|:))|" +
1376                    "(([0-9A-Fa-f]{1,4}:){2}(((:[0-9A-Fa-f]{1,4}){1,5})|" +
1377                    "((:[0-9A-Fa-f]{1,4}){0,3}:((25[0-5]|2[0-4]\\d|1\\d\\d|[1-9]?\\d)" +
1378                    "(\\.(25[0-5]|2[0-4]\\d|1\\d\\d|[1-9]?\\d)){3}))|:))|" +
1379                    "(([0-9A-Fa-f]{1,4}:){1}(((:[0-9A-Fa-f]{1,4}){1,6})|" +
1380                    "((:[0-9A-Fa-f]{1,4}){0,4}:((25[0-5]|2[0-4]\\d|1\\d\\d|[1-9]?\\d)" +
1381                    "(\\.(25[0-5]|2[0-4]\\d|1\\d\\d|[1-9]?\\d)){3}))|:))|" +
1382                    "(:(((:[0-9A-Fa-f]{1,4}){1,7})|((:[0-9A-Fa-f]{1,4}){0,5}:" +
1383                    "((25[0-5]|2[0-4]\\d|1\\d\\d|[1-9]?\\d)(\\." +
1384                    "(25[0-5]|2[0-4]\\d|1\\d\\d|[1-9]?\\d)){3}))|:)))(%.+)?\\s*" +
1385                    "$");
1386            private static Pattern _variableNamePattern = Pattern.compile(
1387                    "[_a-zA-Z]+[_a-zA-Z0-9]*");
1388    
1389    }