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 */
017 package org.apache.commons.lang3;
018
019 import java.lang.reflect.Method;
020 import java.lang.reflect.Modifier;
021 import java.util.ArrayList;
022 import java.util.HashMap;
023 import java.util.HashSet;
024 import java.util.LinkedHashSet;
025 import java.util.List;
026 import java.util.Map;
027
028
029 /**
030 * <p>Operates on classes without using reflection.</p>
031 *
032 * <p>This class handles invalid {@code null} inputs as best it can.
033 * Each method documents its behaviour in more detail.</p>
034 *
035 * <p>The notion of a {@code canonical name} includes the human
036 * readable name for the type, for example {@code int[]}. The
037 * non-canonical method variants work with the JVM names, such as
038 * {@code [I}. </p>
039 *
040 * @since 2.0
041 * @version $Id: ClassUtils.java 1199894 2011-11-09 17:53:59Z ggregory $
042 */
043 public class ClassUtils {
044
045 /**
046 * <p>The package separator character: <code>'.' == {@value}</code>.</p>
047 */
048 public static final char PACKAGE_SEPARATOR_CHAR = '.';
049
050 /**
051 * <p>The package separator String: {@code "."}.</p>
052 */
053 public static final String PACKAGE_SEPARATOR = String.valueOf(PACKAGE_SEPARATOR_CHAR);
054
055 /**
056 * <p>The inner class separator character: <code>'$' == {@value}</code>.</p>
057 */
058 public static final char INNER_CLASS_SEPARATOR_CHAR = '$';
059
060 /**
061 * <p>The inner class separator String: {@code "$"}.</p>
062 */
063 public static final String INNER_CLASS_SEPARATOR = String.valueOf(INNER_CLASS_SEPARATOR_CHAR);
064
065 /**
066 * Maps primitive {@code Class}es to their corresponding wrapper {@code Class}.
067 */
068 private static final Map<Class<?>, Class<?>> primitiveWrapperMap = new HashMap<Class<?>, Class<?>>();
069 static {
070 primitiveWrapperMap.put(Boolean.TYPE, Boolean.class);
071 primitiveWrapperMap.put(Byte.TYPE, Byte.class);
072 primitiveWrapperMap.put(Character.TYPE, Character.class);
073 primitiveWrapperMap.put(Short.TYPE, Short.class);
074 primitiveWrapperMap.put(Integer.TYPE, Integer.class);
075 primitiveWrapperMap.put(Long.TYPE, Long.class);
076 primitiveWrapperMap.put(Double.TYPE, Double.class);
077 primitiveWrapperMap.put(Float.TYPE, Float.class);
078 primitiveWrapperMap.put(Void.TYPE, Void.TYPE);
079 }
080
081 /**
082 * Maps wrapper {@code Class}es to their corresponding primitive types.
083 */
084 private static final Map<Class<?>, Class<?>> wrapperPrimitiveMap = new HashMap<Class<?>, Class<?>>();
085 static {
086 for (Class<?> primitiveClass : primitiveWrapperMap.keySet()) {
087 Class<?> wrapperClass = primitiveWrapperMap.get(primitiveClass);
088 if (!primitiveClass.equals(wrapperClass)) {
089 wrapperPrimitiveMap.put(wrapperClass, primitiveClass);
090 }
091 }
092 }
093
094 /**
095 * Maps a primitive class name to its corresponding abbreviation used in array class names.
096 */
097 private static final Map<String, String> abbreviationMap = new HashMap<String, String>();
098
099 /**
100 * Maps an abbreviation used in array class names to corresponding primitive class name.
101 */
102 private static final Map<String, String> reverseAbbreviationMap = new HashMap<String, String>();
103
104 /**
105 * Add primitive type abbreviation to maps of abbreviations.
106 *
107 * @param primitive Canonical name of primitive type
108 * @param abbreviation Corresponding abbreviation of primitive type
109 */
110 private static void addAbbreviation(String primitive, String abbreviation) {
111 abbreviationMap.put(primitive, abbreviation);
112 reverseAbbreviationMap.put(abbreviation, primitive);
113 }
114
115 /**
116 * Feed abbreviation maps
117 */
118 static {
119 addAbbreviation("int", "I");
120 addAbbreviation("boolean", "Z");
121 addAbbreviation("float", "F");
122 addAbbreviation("long", "J");
123 addAbbreviation("short", "S");
124 addAbbreviation("byte", "B");
125 addAbbreviation("double", "D");
126 addAbbreviation("char", "C");
127 }
128
129 /**
130 * <p>ClassUtils instances should NOT be constructed in standard programming.
131 * Instead, the class should be used as
132 * {@code ClassUtils.getShortClassName(cls)}.</p>
133 *
134 * <p>This constructor is public to permit tools that require a JavaBean
135 * instance to operate.</p>
136 */
137 public ClassUtils() {
138 super();
139 }
140
141 // Short class name
142 // ----------------------------------------------------------------------
143 /**
144 * <p>Gets the class name minus the package name for an {@code Object}.</p>
145 *
146 * @param object the class to get the short name for, may be null
147 * @param valueIfNull the value to return if null
148 * @return the class name of the object without the package name, or the null value
149 */
150 public static String getShortClassName(Object object, String valueIfNull) {
151 if (object == null) {
152 return valueIfNull;
153 }
154 return getShortClassName(object.getClass());
155 }
156
157 /**
158 * <p>Gets the class name minus the package name from a {@code Class}.</p>
159 *
160 * <p>Consider using the Java 5 API {@link Class#getSimpleName()} instead.
161 * The one known difference is that this code will return {@code "Map.Entry"} while
162 * the {@code java.lang.Class} variant will simply return {@code "Entry"}. </p>
163 *
164 * @param cls the class to get the short name for.
165 * @return the class name without the package name or an empty string
166 */
167 public static String getShortClassName(Class<?> cls) {
168 if (cls == null) {
169 return StringUtils.EMPTY;
170 }
171 return getShortClassName(cls.getName());
172 }
173
174 /**
175 * <p>Gets the class name minus the package name from a String.</p>
176 *
177 * <p>The string passed in is assumed to be a class name - it is not checked.</p>
178
179 * <p>Note that this method differs from Class.getSimpleName() in that this will
180 * return {@code "Map.Entry"} whilst the {@code java.lang.Class} variant will simply
181 * return {@code "Entry"}. </p>
182 *
183 * @param className the className to get the short name for
184 * @return the class name of the class without the package name or an empty string
185 */
186 public static String getShortClassName(String className) {
187 if (className == null) {
188 return StringUtils.EMPTY;
189 }
190 if (className.length() == 0) {
191 return StringUtils.EMPTY;
192 }
193
194 StringBuilder arrayPrefix = new StringBuilder();
195
196 // Handle array encoding
197 if (className.startsWith("[")) {
198 while (className.charAt(0) == '[') {
199 className = className.substring(1);
200 arrayPrefix.append("[]");
201 }
202 // Strip Object type encoding
203 if (className.charAt(0) == 'L' && className.charAt(className.length() - 1) == ';') {
204 className = className.substring(1, className.length() - 1);
205 }
206 }
207
208 if (reverseAbbreviationMap.containsKey(className)) {
209 className = reverseAbbreviationMap.get(className);
210 }
211
212 int lastDotIdx = className.lastIndexOf(PACKAGE_SEPARATOR_CHAR);
213 int innerIdx = className.indexOf(
214 INNER_CLASS_SEPARATOR_CHAR, lastDotIdx == -1 ? 0 : lastDotIdx + 1);
215 String out = className.substring(lastDotIdx + 1);
216 if (innerIdx != -1) {
217 out = out.replace(INNER_CLASS_SEPARATOR_CHAR, PACKAGE_SEPARATOR_CHAR);
218 }
219 return out + arrayPrefix;
220 }
221
222 /**
223 * <p>Null-safe version of <code>aClass.getSimpleName()</code></p>
224 *
225 * @param cls the class for which to get the simple name.
226 * @return the simple class name.
227 * @since 3.0
228 * @see Class#getSimpleName()
229 */
230 public static String getSimpleName(Class<?> cls) {
231 if (cls == null) {
232 return StringUtils.EMPTY;
233 }
234 return cls.getSimpleName();
235 }
236
237 /**
238 * <p>Null-safe version of <code>aClass.getSimpleName()</code></p>
239 *
240 * @param object the object for which to get the simple class name.
241 * @param valueIfNull the value to return if <code>object</code> is <code>null</code>
242 * @return the simple class name.
243 * @since 3.0
244 * @see Class#getSimpleName()
245 */
246 public static String getSimpleName(Object object, String valueIfNull) {
247 if (object == null) {
248 return valueIfNull;
249 }
250 return getSimpleName(object.getClass());
251 }
252
253 // Package name
254 // ----------------------------------------------------------------------
255 /**
256 * <p>Gets the package name of an {@code Object}.</p>
257 *
258 * @param object the class to get the package name for, may be null
259 * @param valueIfNull the value to return if null
260 * @return the package name of the object, or the null value
261 */
262 public static String getPackageName(Object object, String valueIfNull) {
263 if (object == null) {
264 return valueIfNull;
265 }
266 return getPackageName(object.getClass());
267 }
268
269 /**
270 * <p>Gets the package name of a {@code Class}.</p>
271 *
272 * @param cls the class to get the package name for, may be {@code null}.
273 * @return the package name or an empty string
274 */
275 public static String getPackageName(Class<?> cls) {
276 if (cls == null) {
277 return StringUtils.EMPTY;
278 }
279 return getPackageName(cls.getName());
280 }
281
282 /**
283 * <p>Gets the package name from a {@code String}.</p>
284 *
285 * <p>The string passed in is assumed to be a class name - it is not checked.</p>
286 * <p>If the class is unpackaged, return an empty string.</p>
287 *
288 * @param className the className to get the package name for, may be {@code null}
289 * @return the package name or an empty string
290 */
291 public static String getPackageName(String className) {
292 if (className == null || className.length() == 0) {
293 return StringUtils.EMPTY;
294 }
295
296 // Strip array encoding
297 while (className.charAt(0) == '[') {
298 className = className.substring(1);
299 }
300 // Strip Object type encoding
301 if (className.charAt(0) == 'L' && className.charAt(className.length() - 1) == ';') {
302 className = className.substring(1);
303 }
304
305 int i = className.lastIndexOf(PACKAGE_SEPARATOR_CHAR);
306 if (i == -1) {
307 return StringUtils.EMPTY;
308 }
309 return className.substring(0, i);
310 }
311
312 // Superclasses/Superinterfaces
313 // ----------------------------------------------------------------------
314 /**
315 * <p>Gets a {@code List} of superclasses for the given class.</p>
316 *
317 * @param cls the class to look up, may be {@code null}
318 * @return the {@code List} of superclasses in order going up from this one
319 * {@code null} if null input
320 */
321 public static List<Class<?>> getAllSuperclasses(Class<?> cls) {
322 if (cls == null) {
323 return null;
324 }
325 List<Class<?>> classes = new ArrayList<Class<?>>();
326 Class<?> superclass = cls.getSuperclass();
327 while (superclass != null) {
328 classes.add(superclass);
329 superclass = superclass.getSuperclass();
330 }
331 return classes;
332 }
333
334 /**
335 * <p>Gets a {@code List} of all interfaces implemented by the given
336 * class and its superclasses.</p>
337 *
338 * <p>The order is determined by looking through each interface in turn as
339 * declared in the source file and following its hierarchy up. Then each
340 * superclass is considered in the same way. Later duplicates are ignored,
341 * so the order is maintained.</p>
342 *
343 * @param cls the class to look up, may be {@code null}
344 * @return the {@code List} of interfaces in order,
345 * {@code null} if null input
346 */
347 public static List<Class<?>> getAllInterfaces(Class<?> cls) {
348 if (cls == null) {
349 return null;
350 }
351
352 LinkedHashSet<Class<?>> interfacesFound = new LinkedHashSet<Class<?>>();
353 getAllInterfaces(cls, interfacesFound);
354
355 return new ArrayList<Class<?>>(interfacesFound);
356 }
357
358 /**
359 * Get the interfaces for the specified class.
360 *
361 * @param cls the class to look up, may be {@code null}
362 * @param interfacesFound the {@code Set} of interfaces for the class
363 */
364 private static void getAllInterfaces(Class<?> cls, HashSet<Class<?>> interfacesFound) {
365 while (cls != null) {
366 Class<?>[] interfaces = cls.getInterfaces();
367
368 for (Class<?> i : interfaces) {
369 if (interfacesFound.add(i)) {
370 getAllInterfaces(i, interfacesFound);
371 }
372 }
373
374 cls = cls.getSuperclass();
375 }
376 }
377
378 // Convert list
379 // ----------------------------------------------------------------------
380 /**
381 * <p>Given a {@code List} of class names, this method converts them into classes.</p>
382 *
383 * <p>A new {@code List} is returned. If the class name cannot be found, {@code null}
384 * is stored in the {@code List}. If the class name in the {@code List} is
385 * {@code null}, {@code null} is stored in the output {@code List}.</p>
386 *
387 * @param classNames the classNames to change
388 * @return a {@code List} of Class objects corresponding to the class names,
389 * {@code null} if null input
390 * @throws ClassCastException if classNames contains a non String entry
391 */
392 public static List<Class<?>> convertClassNamesToClasses(List<String> classNames) {
393 if (classNames == null) {
394 return null;
395 }
396 List<Class<?>> classes = new ArrayList<Class<?>>(classNames.size());
397 for (String className : classNames) {
398 try {
399 classes.add(Class.forName(className));
400 } catch (Exception ex) {
401 classes.add(null);
402 }
403 }
404 return classes;
405 }
406
407 /**
408 * <p>Given a {@code List} of {@code Class} objects, this method converts
409 * them into class names.</p>
410 *
411 * <p>A new {@code List} is returned. {@code null} objects will be copied into
412 * the returned list as {@code null}.</p>
413 *
414 * @param classes the classes to change
415 * @return a {@code List} of class names corresponding to the Class objects,
416 * {@code null} if null input
417 * @throws ClassCastException if {@code classes} contains a non-{@code Class} entry
418 */
419 public static List<String> convertClassesToClassNames(List<Class<?>> classes) {
420 if (classes == null) {
421 return null;
422 }
423 List<String> classNames = new ArrayList<String>(classes.size());
424 for (Class<?> cls : classes) {
425 if (cls == null) {
426 classNames.add(null);
427 } else {
428 classNames.add(cls.getName());
429 }
430 }
431 return classNames;
432 }
433
434 // Is assignable
435 // ----------------------------------------------------------------------
436 /**
437 * <p>Checks if an array of Classes can be assigned to another array of Classes.</p>
438 *
439 * <p>This method calls {@link #isAssignable(Class, Class) isAssignable} for each
440 * Class pair in the input arrays. It can be used to check if a set of arguments
441 * (the first parameter) are suitably compatible with a set of method parameter types
442 * (the second parameter).</p>
443 *
444 * <p>Unlike the {@link Class#isAssignableFrom(java.lang.Class)} method, this
445 * method takes into account widenings of primitive classes and
446 * {@code null}s.</p>
447 *
448 * <p>Primitive widenings allow an int to be assigned to a {@code long},
449 * {@code float} or {@code double}. This method returns the correct
450 * result for these cases.</p>
451 *
452 * <p>{@code Null} may be assigned to any reference type. This method will
453 * return {@code true} if {@code null} is passed in and the toClass is
454 * non-primitive.</p>
455 *
456 * <p>Specifically, this method tests whether the type represented by the
457 * specified {@code Class} parameter can be converted to the type
458 * represented by this {@code Class} object via an identity conversion
459 * widening primitive or widening reference conversion. See
460 * <em><a href="http://java.sun.com/docs/books/jls/">The Java Language Specification</a></em>,
461 * sections 5.1.1, 5.1.2 and 5.1.4 for details.</p>
462 *
463 * <p><strong>Since Lang 3.0,</strong> this method will default behavior for
464 * calculating assignability between primitive and wrapper types <em>corresponding
465 * to the running Java version</em>; i.e. autoboxing will be the default
466 * behavior in VMs running Java versions >= 1.5.</p>
467 *
468 * @param classArray the array of Classes to check, may be {@code null}
469 * @param toClassArray the array of Classes to try to assign into, may be {@code null}
470 * @return {@code true} if assignment possible
471 */
472 public static boolean isAssignable(Class<?>[] classArray, Class<?>... toClassArray) {
473 return isAssignable(classArray, toClassArray, SystemUtils.isJavaVersionAtLeast(JavaVersion.JAVA_1_5));
474 }
475
476 /**
477 * <p>Checks if an array of Classes can be assigned to another array of Classes.</p>
478 *
479 * <p>This method calls {@link #isAssignable(Class, Class) isAssignable} for each
480 * Class pair in the input arrays. It can be used to check if a set of arguments
481 * (the first parameter) are suitably compatible with a set of method parameter types
482 * (the second parameter).</p>
483 *
484 * <p>Unlike the {@link Class#isAssignableFrom(java.lang.Class)} method, this
485 * method takes into account widenings of primitive classes and
486 * {@code null}s.</p>
487 *
488 * <p>Primitive widenings allow an int to be assigned to a {@code long},
489 * {@code float} or {@code double}. This method returns the correct
490 * result for these cases.</p>
491 *
492 * <p>{@code Null} may be assigned to any reference type. This method will
493 * return {@code true} if {@code null} is passed in and the toClass is
494 * non-primitive.</p>
495 *
496 * <p>Specifically, this method tests whether the type represented by the
497 * specified {@code Class} parameter can be converted to the type
498 * represented by this {@code Class} object via an identity conversion
499 * widening primitive or widening reference conversion. See
500 * <em><a href="http://java.sun.com/docs/books/jls/">The Java Language Specification</a></em>,
501 * sections 5.1.1, 5.1.2 and 5.1.4 for details.</p>
502 *
503 * @param classArray the array of Classes to check, may be {@code null}
504 * @param toClassArray the array of Classes to try to assign into, may be {@code null}
505 * @param autoboxing whether to use implicit autoboxing/unboxing between primitives and wrappers
506 * @return {@code true} if assignment possible
507 */
508 public static boolean isAssignable(Class<?>[] classArray, Class<?>[] toClassArray, boolean autoboxing) {
509 if (ArrayUtils.isSameLength(classArray, toClassArray) == false) {
510 return false;
511 }
512 if (classArray == null) {
513 classArray = ArrayUtils.EMPTY_CLASS_ARRAY;
514 }
515 if (toClassArray == null) {
516 toClassArray = ArrayUtils.EMPTY_CLASS_ARRAY;
517 }
518 for (int i = 0; i < classArray.length; i++) {
519 if (isAssignable(classArray[i], toClassArray[i], autoboxing) == false) {
520 return false;
521 }
522 }
523 return true;
524 }
525
526 /**
527 * Returns whether the given {@code type} is a primitive or primitive wrapper ({@link Boolean}, {@link Byte}, {@link Character},
528 * {@link Short}, {@link Integer}, {@link Long}, {@link Double}, {@link Float}).
529 *
530 * @param type
531 * The class to query or null.
532 * @return true if the given {@code type} is a primitive or primitive wrapper ({@link Boolean}, {@link Byte}, {@link Character},
533 * {@link Short}, {@link Integer}, {@link Long}, {@link Double}, {@link Float}).
534 * @since 3.1
535 */
536 public static boolean isPrimitiveOrWrapper(Class<?> type) {
537 if (type == null) {
538 return false;
539 }
540 return type.isPrimitive() || isPrimitiveWrapper(type);
541 }
542
543 /**
544 * Returns whether the given {@code type} is a primitive wrapper ({@link Boolean}, {@link Byte}, {@link Character}, {@link Short},
545 * {@link Integer}, {@link Long}, {@link Double}, {@link Float}).
546 *
547 * @param type
548 * The class to query or null.
549 * @return true if the given {@code type} is a primitive wrapper ({@link Boolean}, {@link Byte}, {@link Character}, {@link Short},
550 * {@link Integer}, {@link Long}, {@link Double}, {@link Float}).
551 * @since 3.1
552 */
553 public static boolean isPrimitiveWrapper(Class<?> type) {
554 return wrapperPrimitiveMap.containsKey(type);
555 }
556
557 /**
558 * <p>Checks if one {@code Class} can be assigned to a variable of
559 * another {@code Class}.</p>
560 *
561 * <p>Unlike the {@link Class#isAssignableFrom(java.lang.Class)} method,
562 * this method takes into account widenings of primitive classes and
563 * {@code null}s.</p>
564 *
565 * <p>Primitive widenings allow an int to be assigned to a long, float or
566 * double. This method returns the correct result for these cases.</p>
567 *
568 * <p>{@code Null} may be assigned to any reference type. This method
569 * will return {@code true} if {@code null} is passed in and the
570 * toClass is non-primitive.</p>
571 *
572 * <p>Specifically, this method tests whether the type represented by the
573 * specified {@code Class} parameter can be converted to the type
574 * represented by this {@code Class} object via an identity conversion
575 * widening primitive or widening reference conversion. See
576 * <em><a href="http://java.sun.com/docs/books/jls/">The Java Language Specification</a></em>,
577 * sections 5.1.1, 5.1.2 and 5.1.4 for details.</p>
578 *
579 * <p><strong>Since Lang 3.0,</strong> this method will default behavior for
580 * calculating assignability between primitive and wrapper types <em>corresponding
581 * to the running Java version</em>; i.e. autoboxing will be the default
582 * behavior in VMs running Java versions >= 1.5.</p>
583 *
584 * @param cls the Class to check, may be null
585 * @param toClass the Class to try to assign into, returns false if null
586 * @return {@code true} if assignment possible
587 */
588 public static boolean isAssignable(Class<?> cls, Class<?> toClass) {
589 return isAssignable(cls, toClass, SystemUtils.isJavaVersionAtLeast(JavaVersion.JAVA_1_5));
590 }
591
592 /**
593 * <p>Checks if one {@code Class} can be assigned to a variable of
594 * another {@code Class}.</p>
595 *
596 * <p>Unlike the {@link Class#isAssignableFrom(java.lang.Class)} method,
597 * this method takes into account widenings of primitive classes and
598 * {@code null}s.</p>
599 *
600 * <p>Primitive widenings allow an int to be assigned to a long, float or
601 * double. This method returns the correct result for these cases.</p>
602 *
603 * <p>{@code Null} may be assigned to any reference type. This method
604 * will return {@code true} if {@code null} is passed in and the
605 * toClass is non-primitive.</p>
606 *
607 * <p>Specifically, this method tests whether the type represented by the
608 * specified {@code Class} parameter can be converted to the type
609 * represented by this {@code Class} object via an identity conversion
610 * widening primitive or widening reference conversion. See
611 * <em><a href="http://java.sun.com/docs/books/jls/">The Java Language Specification</a></em>,
612 * sections 5.1.1, 5.1.2 and 5.1.4 for details.</p>
613 *
614 * @param cls the Class to check, may be null
615 * @param toClass the Class to try to assign into, returns false if null
616 * @param autoboxing whether to use implicit autoboxing/unboxing between primitives and wrappers
617 * @return {@code true} if assignment possible
618 */
619 public static boolean isAssignable(Class<?> cls, Class<?> toClass, boolean autoboxing) {
620 if (toClass == null) {
621 return false;
622 }
623 // have to check for null, as isAssignableFrom doesn't
624 if (cls == null) {
625 return !toClass.isPrimitive();
626 }
627 //autoboxing:
628 if (autoboxing) {
629 if (cls.isPrimitive() && !toClass.isPrimitive()) {
630 cls = primitiveToWrapper(cls);
631 if (cls == null) {
632 return false;
633 }
634 }
635 if (toClass.isPrimitive() && !cls.isPrimitive()) {
636 cls = wrapperToPrimitive(cls);
637 if (cls == null) {
638 return false;
639 }
640 }
641 }
642 if (cls.equals(toClass)) {
643 return true;
644 }
645 if (cls.isPrimitive()) {
646 if (toClass.isPrimitive() == false) {
647 return false;
648 }
649 if (Integer.TYPE.equals(cls)) {
650 return Long.TYPE.equals(toClass)
651 || Float.TYPE.equals(toClass)
652 || Double.TYPE.equals(toClass);
653 }
654 if (Long.TYPE.equals(cls)) {
655 return Float.TYPE.equals(toClass)
656 || Double.TYPE.equals(toClass);
657 }
658 if (Boolean.TYPE.equals(cls)) {
659 return false;
660 }
661 if (Double.TYPE.equals(cls)) {
662 return false;
663 }
664 if (Float.TYPE.equals(cls)) {
665 return Double.TYPE.equals(toClass);
666 }
667 if (Character.TYPE.equals(cls)) {
668 return Integer.TYPE.equals(toClass)
669 || Long.TYPE.equals(toClass)
670 || Float.TYPE.equals(toClass)
671 || Double.TYPE.equals(toClass);
672 }
673 if (Short.TYPE.equals(cls)) {
674 return Integer.TYPE.equals(toClass)
675 || Long.TYPE.equals(toClass)
676 || Float.TYPE.equals(toClass)
677 || Double.TYPE.equals(toClass);
678 }
679 if (Byte.TYPE.equals(cls)) {
680 return Short.TYPE.equals(toClass)
681 || Integer.TYPE.equals(toClass)
682 || Long.TYPE.equals(toClass)
683 || Float.TYPE.equals(toClass)
684 || Double.TYPE.equals(toClass);
685 }
686 // should never get here
687 return false;
688 }
689 return toClass.isAssignableFrom(cls);
690 }
691
692 /**
693 * <p>Converts the specified primitive Class object to its corresponding
694 * wrapper Class object.</p>
695 *
696 * <p>NOTE: From v2.2, this method handles {@code Void.TYPE},
697 * returning {@code Void.TYPE}.</p>
698 *
699 * @param cls the class to convert, may be null
700 * @return the wrapper class for {@code cls} or {@code cls} if
701 * {@code cls} is not a primitive. {@code null} if null input.
702 * @since 2.1
703 */
704 public static Class<?> primitiveToWrapper(Class<?> cls) {
705 Class<?> convertedClass = cls;
706 if (cls != null && cls.isPrimitive()) {
707 convertedClass = primitiveWrapperMap.get(cls);
708 }
709 return convertedClass;
710 }
711
712 /**
713 * <p>Converts the specified array of primitive Class objects to an array of
714 * its corresponding wrapper Class objects.</p>
715 *
716 * @param classes the class array to convert, may be null or empty
717 * @return an array which contains for each given class, the wrapper class or
718 * the original class if class is not a primitive. {@code null} if null input.
719 * Empty array if an empty array passed in.
720 * @since 2.1
721 */
722 public static Class<?>[] primitivesToWrappers(Class<?>... classes) {
723 if (classes == null) {
724 return null;
725 }
726
727 if (classes.length == 0) {
728 return classes;
729 }
730
731 Class<?>[] convertedClasses = new Class[classes.length];
732 for (int i = 0; i < classes.length; i++) {
733 convertedClasses[i] = primitiveToWrapper(classes[i]);
734 }
735 return convertedClasses;
736 }
737
738 /**
739 * <p>Converts the specified wrapper class to its corresponding primitive
740 * class.</p>
741 *
742 * <p>This method is the counter part of {@code primitiveToWrapper()}.
743 * If the passed in class is a wrapper class for a primitive type, this
744 * primitive type will be returned (e.g. {@code Integer.TYPE} for
745 * {@code Integer.class}). For other classes, or if the parameter is
746 * <b>null</b>, the return value is <b>null</b>.</p>
747 *
748 * @param cls the class to convert, may be <b>null</b>
749 * @return the corresponding primitive type if {@code cls} is a
750 * wrapper class, <b>null</b> otherwise
751 * @see #primitiveToWrapper(Class)
752 * @since 2.4
753 */
754 public static Class<?> wrapperToPrimitive(Class<?> cls) {
755 return wrapperPrimitiveMap.get(cls);
756 }
757
758 /**
759 * <p>Converts the specified array of wrapper Class objects to an array of
760 * its corresponding primitive Class objects.</p>
761 *
762 * <p>This method invokes {@code wrapperToPrimitive()} for each element
763 * of the passed in array.</p>
764 *
765 * @param classes the class array to convert, may be null or empty
766 * @return an array which contains for each given class, the primitive class or
767 * <b>null</b> if the original class is not a wrapper class. {@code null} if null input.
768 * Empty array if an empty array passed in.
769 * @see #wrapperToPrimitive(Class)
770 * @since 2.4
771 */
772 public static Class<?>[] wrappersToPrimitives(Class<?>... classes) {
773 if (classes == null) {
774 return null;
775 }
776
777 if (classes.length == 0) {
778 return classes;
779 }
780
781 Class<?>[] convertedClasses = new Class[classes.length];
782 for (int i = 0; i < classes.length; i++) {
783 convertedClasses[i] = wrapperToPrimitive(classes[i]);
784 }
785 return convertedClasses;
786 }
787
788 // Inner class
789 // ----------------------------------------------------------------------
790 /**
791 * <p>Is the specified class an inner class or static nested class.</p>
792 *
793 * @param cls the class to check, may be null
794 * @return {@code true} if the class is an inner or static nested class,
795 * false if not or {@code null}
796 */
797 public static boolean isInnerClass(Class<?> cls) {
798 return cls != null && cls.getEnclosingClass() != null;
799 }
800
801 // Class loading
802 // ----------------------------------------------------------------------
803 /**
804 * Returns the class represented by {@code className} using the
805 * {@code classLoader}. This implementation supports the syntaxes
806 * "{@code java.util.Map.Entry[]}", "{@code java.util.Map$Entry[]}",
807 * "{@code [Ljava.util.Map.Entry;}", and "{@code [Ljava.util.Map$Entry;}".
808 *
809 * @param classLoader the class loader to use to load the class
810 * @param className the class name
811 * @param initialize whether the class must be initialized
812 * @return the class represented by {@code className} using the {@code classLoader}
813 * @throws ClassNotFoundException if the class is not found
814 */
815 public static Class<?> getClass(
816 ClassLoader classLoader, String className, boolean initialize) throws ClassNotFoundException {
817 try {
818 Class<?> clazz;
819 if (abbreviationMap.containsKey(className)) {
820 String clsName = "[" + abbreviationMap.get(className);
821 clazz = Class.forName(clsName, initialize, classLoader).getComponentType();
822 } else {
823 clazz = Class.forName(toCanonicalName(className), initialize, classLoader);
824 }
825 return clazz;
826 } catch (ClassNotFoundException ex) {
827 // allow path separators (.) as inner class name separators
828 int lastDotIndex = className.lastIndexOf(PACKAGE_SEPARATOR_CHAR);
829
830 if (lastDotIndex != -1) {
831 try {
832 return getClass(classLoader, className.substring(0, lastDotIndex) +
833 INNER_CLASS_SEPARATOR_CHAR + className.substring(lastDotIndex + 1),
834 initialize);
835 } catch (ClassNotFoundException ex2) { // NOPMD
836 // ignore exception
837 }
838 }
839
840 throw ex;
841 }
842 }
843
844 /**
845 * Returns the (initialized) class represented by {@code className}
846 * using the {@code classLoader}. This implementation supports
847 * the syntaxes "{@code java.util.Map.Entry[]}",
848 * "{@code java.util.Map$Entry[]}", "{@code [Ljava.util.Map.Entry;}",
849 * and "{@code [Ljava.util.Map$Entry;}".
850 *
851 * @param classLoader the class loader to use to load the class
852 * @param className the class name
853 * @return the class represented by {@code className} using the {@code classLoader}
854 * @throws ClassNotFoundException if the class is not found
855 */
856 public static Class<?> getClass(ClassLoader classLoader, String className) throws ClassNotFoundException {
857 return getClass(classLoader, className, true);
858 }
859
860 /**
861 * Returns the (initialized) class represented by {@code className}
862 * using the current thread's context class loader. This implementation
863 * supports the syntaxes "{@code java.util.Map.Entry[]}",
864 * "{@code java.util.Map$Entry[]}", "{@code [Ljava.util.Map.Entry;}",
865 * and "{@code [Ljava.util.Map$Entry;}".
866 *
867 * @param className the class name
868 * @return the class represented by {@code className} using the current thread's context class loader
869 * @throws ClassNotFoundException if the class is not found
870 */
871 public static Class<?> getClass(String className) throws ClassNotFoundException {
872 return getClass(className, true);
873 }
874
875 /**
876 * Returns the class represented by {@code className} using the
877 * current thread's context class loader. This implementation supports the
878 * syntaxes "{@code java.util.Map.Entry[]}", "{@code java.util.Map$Entry[]}",
879 * "{@code [Ljava.util.Map.Entry;}", and "{@code [Ljava.util.Map$Entry;}".
880 *
881 * @param className the class name
882 * @param initialize whether the class must be initialized
883 * @return the class represented by {@code className} using the current thread's context class loader
884 * @throws ClassNotFoundException if the class is not found
885 */
886 public static Class<?> getClass(String className, boolean initialize) throws ClassNotFoundException {
887 ClassLoader contextCL = Thread.currentThread().getContextClassLoader();
888 ClassLoader loader = contextCL == null ? ClassUtils.class.getClassLoader() : contextCL;
889 return getClass(loader, className, initialize);
890 }
891
892 // Public method
893 // ----------------------------------------------------------------------
894 /**
895 * <p>Returns the desired Method much like {@code Class.getMethod}, however
896 * it ensures that the returned Method is from a public class or interface and not
897 * from an anonymous inner class. This means that the Method is invokable and
898 * doesn't fall foul of Java bug
899 * <a href="http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4071957">4071957</a>).
900 *
901 * <code><pre>Set set = Collections.unmodifiableSet(...);
902 * Method method = ClassUtils.getPublicMethod(set.getClass(), "isEmpty", new Class[0]);
903 * Object result = method.invoke(set, new Object[]);</pre></code>
904 * </p>
905 *
906 * @param cls the class to check, not null
907 * @param methodName the name of the method
908 * @param parameterTypes the list of parameters
909 * @return the method
910 * @throws NullPointerException if the class is null
911 * @throws SecurityException if a a security violation occured
912 * @throws NoSuchMethodException if the method is not found in the given class
913 * or if the metothod doen't conform with the requirements
914 */
915 public static Method getPublicMethod(Class<?> cls, String methodName, Class<?>... parameterTypes)
916 throws SecurityException, NoSuchMethodException {
917
918 Method declaredMethod = cls.getMethod(methodName, parameterTypes);
919 if (Modifier.isPublic(declaredMethod.getDeclaringClass().getModifiers())) {
920 return declaredMethod;
921 }
922
923 List<Class<?>> candidateClasses = new ArrayList<Class<?>>();
924 candidateClasses.addAll(getAllInterfaces(cls));
925 candidateClasses.addAll(getAllSuperclasses(cls));
926
927 for (Class<?> candidateClass : candidateClasses) {
928 if (!Modifier.isPublic(candidateClass.getModifiers())) {
929 continue;
930 }
931 Method candidateMethod;
932 try {
933 candidateMethod = candidateClass.getMethod(methodName, parameterTypes);
934 } catch (NoSuchMethodException ex) {
935 continue;
936 }
937 if (Modifier.isPublic(candidateMethod.getDeclaringClass().getModifiers())) {
938 return candidateMethod;
939 }
940 }
941
942 throw new NoSuchMethodException("Can't find a public method for " +
943 methodName + " " + ArrayUtils.toString(parameterTypes));
944 }
945
946 // ----------------------------------------------------------------------
947 /**
948 * Converts a class name to a JLS style class name.
949 *
950 * @param className the class name
951 * @return the converted name
952 */
953 private static String toCanonicalName(String className) {
954 className = StringUtils.deleteWhitespace(className);
955 if (className == null) {
956 throw new NullPointerException("className must not be null.");
957 } else if (className.endsWith("[]")) {
958 StringBuilder classNameBuffer = new StringBuilder();
959 while (className.endsWith("[]")) {
960 className = className.substring(0, className.length() - 2);
961 classNameBuffer.append("[");
962 }
963 String abbreviation = abbreviationMap.get(className);
964 if (abbreviation != null) {
965 classNameBuffer.append(abbreviation);
966 } else {
967 classNameBuffer.append("L").append(className).append(";");
968 }
969 className = classNameBuffer.toString();
970 }
971 return className;
972 }
973
974 /**
975 * <p>Converts an array of {@code Object} in to an array of {@code Class} objects.
976 * If any of these objects is null, a null element will be inserted into the array.</p>
977 *
978 * <p>This method returns {@code null} for a {@code null} input array.</p>
979 *
980 * @param array an {@code Object} array
981 * @return a {@code Class} array, {@code null} if null array input
982 * @since 2.4
983 */
984 public static Class<?>[] toClass(Object... array) {
985 if (array == null) {
986 return null;
987 } else if (array.length == 0) {
988 return ArrayUtils.EMPTY_CLASS_ARRAY;
989 }
990 Class<?>[] classes = new Class[array.length];
991 for (int i = 0; i < array.length; i++) {
992 classes[i] = array[i] == null ? null : array[i].getClass();
993 }
994 return classes;
995 }
996
997 // Short canonical name
998 // ----------------------------------------------------------------------
999 /**
1000 * <p>Gets the canonical name minus the package name for an {@code Object}.</p>
1001 *
1002 * @param object the class to get the short name for, may be null
1003 * @param valueIfNull the value to return if null
1004 * @return the canonical name of the object without the package name, or the null value
1005 * @since 2.4
1006 */
1007 public static String getShortCanonicalName(Object object, String valueIfNull) {
1008 if (object == null) {
1009 return valueIfNull;
1010 }
1011 return getShortCanonicalName(object.getClass().getName());
1012 }
1013
1014 /**
1015 * <p>Gets the canonical name minus the package name from a {@code Class}.</p>
1016 *
1017 * @param cls the class to get the short name for.
1018 * @return the canonical name without the package name or an empty string
1019 * @since 2.4
1020 */
1021 public static String getShortCanonicalName(Class<?> cls) {
1022 if (cls == null) {
1023 return StringUtils.EMPTY;
1024 }
1025 return getShortCanonicalName(cls.getName());
1026 }
1027
1028 /**
1029 * <p>Gets the canonical name minus the package name from a String.</p>
1030 *
1031 * <p>The string passed in is assumed to be a canonical name - it is not checked.</p>
1032 *
1033 * @param canonicalName the class name to get the short name for
1034 * @return the canonical name of the class without the package name or an empty string
1035 * @since 2.4
1036 */
1037 public static String getShortCanonicalName(String canonicalName) {
1038 return ClassUtils.getShortClassName(getCanonicalName(canonicalName));
1039 }
1040
1041 // Package name
1042 // ----------------------------------------------------------------------
1043 /**
1044 * <p>Gets the package name from the canonical name of an {@code Object}.</p>
1045 *
1046 * @param object the class to get the package name for, may be null
1047 * @param valueIfNull the value to return if null
1048 * @return the package name of the object, or the null value
1049 * @since 2.4
1050 */
1051 public static String getPackageCanonicalName(Object object, String valueIfNull) {
1052 if (object == null) {
1053 return valueIfNull;
1054 }
1055 return getPackageCanonicalName(object.getClass().getName());
1056 }
1057
1058 /**
1059 * <p>Gets the package name from the canonical name of a {@code Class}.</p>
1060 *
1061 * @param cls the class to get the package name for, may be {@code null}.
1062 * @return the package name or an empty string
1063 * @since 2.4
1064 */
1065 public static String getPackageCanonicalName(Class<?> cls) {
1066 if (cls == null) {
1067 return StringUtils.EMPTY;
1068 }
1069 return getPackageCanonicalName(cls.getName());
1070 }
1071
1072 /**
1073 * <p>Gets the package name from the canonical name. </p>
1074 *
1075 * <p>The string passed in is assumed to be a canonical name - it is not checked.</p>
1076 * <p>If the class is unpackaged, return an empty string.</p>
1077 *
1078 * @param canonicalName the canonical name to get the package name for, may be {@code null}
1079 * @return the package name or an empty string
1080 * @since 2.4
1081 */
1082 public static String getPackageCanonicalName(String canonicalName) {
1083 return ClassUtils.getPackageName(getCanonicalName(canonicalName));
1084 }
1085
1086 /**
1087 * <p>Converts a given name of class into canonical format.
1088 * If name of class is not a name of array class it returns
1089 * unchanged name.</p>
1090 * <p>Example:
1091 * <ul>
1092 * <li>{@code getCanonicalName("[I") = "int[]"}</li>
1093 * <li>{@code getCanonicalName("[Ljava.lang.String;") = "java.lang.String[]"}</li>
1094 * <li>{@code getCanonicalName("java.lang.String") = "java.lang.String"}</li>
1095 * </ul>
1096 * </p>
1097 *
1098 * @param className the name of class
1099 * @return canonical form of class name
1100 * @since 2.4
1101 */
1102 private static String getCanonicalName(String className) {
1103 className = StringUtils.deleteWhitespace(className);
1104 if (className == null) {
1105 return null;
1106 } else {
1107 int dim = 0;
1108 while (className.startsWith("[")) {
1109 dim++;
1110 className = className.substring(1);
1111 }
1112 if (dim < 1) {
1113 return className;
1114 } else {
1115 if (className.startsWith("L")) {
1116 className = className.substring(
1117 1,
1118 className.endsWith(";")
1119 ? className.length() - 1
1120 : className.length());
1121 } else {
1122 if (className.length() > 0) {
1123 className = reverseAbbreviationMap.get(className.substring(0, 1));
1124 }
1125 }
1126 StringBuilder canonicalClassNameBuffer = new StringBuilder(className);
1127 for (int i = 0; i < dim; i++) {
1128 canonicalClassNameBuffer.append("[]");
1129 }
1130 return canonicalClassNameBuffer.toString();
1131 }
1132 }
1133 }
1134
1135 }