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1 /*
2  * Javassist, a Java-bytecode translator toolkit.
3  * Copyright (C) 1999- Shigeru Chiba. All Rights Reserved.
4  *
5  * The contents of this file are subject to the Mozilla Public License Version
6  * 1.1 (the "License"); you may not use this file except in compliance with
7  * the License.  Alternatively, the contents of this file may be used under
8  * the terms of the GNU Lesser General Public License Version 2.1 or later,
9  * or the Apache License Version 2.0.
10  *
11  * Software distributed under the License is distributed on an "AS IS" basis,
12  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
13  * for the specific language governing rights and limitations under the
14  * License.
15  */
16 
17 package javassist;
18 
19 import java.io.BufferedOutputStream;
20 import java.io.ByteArrayOutputStream;
21 import java.io.DataOutputStream;
22 import java.io.File;
23 import java.io.FileOutputStream;
24 import java.io.IOException;
25 import java.io.OutputStream;
26 import java.net.URL;
27 import java.security.ProtectionDomain;
28 import java.util.Collection;
29 
30 import javassist.bytecode.ClassFile;
31 import javassist.bytecode.Descriptor;
32 import javassist.bytecode.Opcode;
33 import javassist.expr.ExprEditor;
34 
35 /* Note:
36  *
37  * This class is an abstract class and several methods just return null
38  * or throw an exception.  Those methods are overridden in subclasses
39  * of this class.  Read the source code of CtClassType if you are
40  * interested in the implementation of Javassist.
41  *
42  * Subclasses of CtClass are CtClassType, CtPrimitiveType, and CtArray.
43  */
44 
45 /**
46  * An instance of <code>CtClass</code> represents a class.
47  * It is obtained from <code>ClassPool</code>.
48  *
49  * @see ClassPool#get(String)
50  */
51 public abstract class CtClass {
52     protected String qualifiedName;
53 
54     /**
55      * If the value of this field is not null, then all class
56      * files modified by Javassist are saved under the directory
57      * specified by this variable.  For example, if the value is
58      * <code>"./debug"</code>, then all class files are saved
59      * there.  The directory name must not end with a directory
60      * separator such as <code>/</code>.
61      *
62      * <p>The default value is null.
63      *
64      * @see #debugWriteFile(String)
65      * @since 3.16
66      */
67     public static String debugDump = null;
68 
69     /**
70      * The version number of this release.
71      */
72     public static final String version = "3.24.1-GA";
73 
74     /**
75      * Prints the version number and the copyright notice.
76      *
77      * <p>The following command invokes this method:
78      *
79      * <pre>java -jar javassist.jar</pre>
80      */
main(String[] args)81     public static void main(String[] args) {
82         System.out.println("Javassist version " + CtClass.version);
83         System.out.println("Copyright (C) 1999-2018 Shigeru Chiba."
84                            + " All Rights Reserved.");
85     }
86 
87     static final String javaLangObject = "java.lang.Object";
88 
89     /**
90      * The <code>CtClass</code> object representing
91      * the <code>boolean</code> type.
92      */
93     public static CtClass booleanType;
94 
95     /**
96      * The <code>CtClass</code> object representing
97      * the <code>char</code> type.
98      */
99     public static CtClass charType;
100 
101     /**
102      * The <code>CtClass</code> object representing
103      * the <code>byte</code> type.
104      */
105     public static CtClass byteType;
106 
107     /**
108      * The <code>CtClass</code> object representing
109      * the <code>short</code> type.
110      */
111     public static CtClass shortType;
112 
113     /**
114      * The <code>CtClass</code> object representing
115      * the <code>int</code> type.
116      */
117     public static CtClass intType;
118 
119     /**
120      * The <code>CtClass</code> object representing
121      * the <code>long</code> type.
122      */
123     public static CtClass longType;
124 
125     /**
126      * The <code>CtClass</code> object representing
127      * the <code>float</code> type.
128      */
129     public static CtClass floatType;
130 
131     /**
132      * The <code>CtClass</code> object representing
133      * the <code>double</code> type.
134      */
135     public static CtClass doubleType;
136 
137     /**
138      * The <code>CtClass</code> object representing
139      * the <code>void</code> type.
140      */
141     public static CtClass voidType;
142 
143     static CtClass[] primitiveTypes;
144 
145     static {
146         primitiveTypes = new CtClass[9];
147 
148         booleanType =
149             new CtPrimitiveType("boolean", 'Z', "java.lang.Boolean",
150                                 "booleanValue", "()Z", Opcode.IRETURN,
151                                 Opcode.T_BOOLEAN, 1);
152         primitiveTypes[0] = booleanType;
153 
154         charType = new CtPrimitiveType("char", 'C', "java.lang.Character",
155                                        "charValue", "()C", Opcode.IRETURN,
156                                        Opcode.T_CHAR, 1);
157         primitiveTypes[1] = charType;
158 
159         byteType = new CtPrimitiveType("byte", 'B', "java.lang.Byte",
160                                        "byteValue", "()B", Opcode.IRETURN,
161                                        Opcode.T_BYTE, 1);
162         primitiveTypes[2] = byteType;
163 
164         shortType = new CtPrimitiveType("short", 'S', "java.lang.Short",
165                                         "shortValue", "()S", Opcode.IRETURN,
166                                         Opcode.T_SHORT, 1);
167         primitiveTypes[3] = shortType;
168 
169         intType = new CtPrimitiveType("int", 'I', "java.lang.Integer",
170                                       "intValue", "()I", Opcode.IRETURN,
171                                       Opcode.T_INT, 1);
172         primitiveTypes[4] = intType;
173 
174         longType = new CtPrimitiveType("long", 'J', "java.lang.Long",
175                                        "longValue", "()J", Opcode.LRETURN,
176                                        Opcode.T_LONG, 2);
177         primitiveTypes[5] = longType;
178 
179         floatType = new CtPrimitiveType("float", 'F', "java.lang.Float",
180                                         "floatValue", "()F", Opcode.FRETURN,
181                                         Opcode.T_FLOAT, 1);
182         primitiveTypes[6] = floatType;
183 
184         doubleType = new CtPrimitiveType("double", 'D', "java.lang.Double",
185                                          "doubleValue", "()D", Opcode.DRETURN,
186                                          Opcode.T_DOUBLE, 2);
187         primitiveTypes[7] = doubleType;
188 
189         voidType = new CtPrimitiveType("void", 'V', "java.lang.Void",
190                                        null, null, Opcode.RETURN, 0, 0);
191         primitiveTypes[8] = voidType;
192     }
193 
CtClass(String name)194     protected CtClass(String name) {
195         qualifiedName = name;
196     }
197 
198     /**
199      * Converts the object to a string.
200      */
201     @Override
toString()202     public String toString() {
203         StringBuffer buf = new StringBuffer(getClass().getName());
204         buf.append("@");
205         buf.append(Integer.toHexString(hashCode()));
206         buf.append("[");
207         extendToString(buf);
208         buf.append("]");
209         return buf.toString();
210     }
211 
212     /**
213      * Implemented in subclasses to add to the {@link #toString()} result.
214      * Subclasses should put a space before each token added to the buffer.
215      */
extendToString(StringBuffer buffer)216     protected void extendToString(StringBuffer buffer) {
217         buffer.append(getName());
218     }
219 
220     /**
221      * Returns a <code>ClassPool</code> for this class.
222      */
getClassPool()223     public ClassPool getClassPool() { return null; }
224 
225     /**
226      * Returns a class file for this class.
227      *
228      * <p>This method is not available if <code>isFrozen()</code>
229      * is true.
230      */
getClassFile()231     public ClassFile getClassFile() {
232         checkModify();
233         return getClassFile2();
234     }
235 
236     /**
237      * Returns a class file for this class (read only).
238      * Normal applications do not need calling this method.  Use
239      * <code>getClassFile()</code>.
240      *
241      * <p>The <code>ClassFile</code> object obtained by this method
242      * is read only.  Changes to this object might not be reflected
243      * on a class file generated by <code>toBytecode()</code>,
244      * <code>toClass()</code>, etc.
245      *
246      * <p>This method is available even if <code>isFrozen()</code>
247      * is true.  However, if the class is frozen, it might be also
248      * pruned.
249      *
250      * @see CtClass#getClassFile()
251      * @see CtClass#isFrozen()
252      * @see CtClass#prune()
253      */
getClassFile2()254     public ClassFile getClassFile2() { return null; }
255 
256     /**
257      * Undocumented method.  Do not use; internal-use only.
258      */
getAccessorMaker()259     public javassist.compiler.AccessorMaker getAccessorMaker() {
260         return null;
261     }
262 
263     /**
264      * Returns the uniform resource locator (URL) of the class file.
265      */
getURL()266     public URL getURL() throws NotFoundException {
267         throw new NotFoundException(getName());
268     }
269 
270     /**
271      * Returns true if the definition of the class has been modified.
272      */
isModified()273     public boolean isModified() { return false; }
274 
275     /**
276      * Returns true if the class has been loaded or written out
277      * and thus it cannot be modified any more.
278      *
279      * @see #defrost()
280      * @see #detach()
281      */
isFrozen()282     public boolean isFrozen() { return true; }
283 
284     /**
285      * Makes the class frozen.
286      *
287      * @see #isFrozen()
288      * @see #defrost()
289      * @since 3.6
290      */
freeze()291     public void freeze() {}
292 
293     /* Note: this method is overridden by CtClassType
294      */
checkModify()295     void checkModify() throws RuntimeException {
296         if (isFrozen())
297             throw new RuntimeException(getName() + " class is frozen");
298 
299         // isModified() must return true after this method is invoked.
300     }
301 
302     /**
303      * Defrosts the class so that the class can be modified again.
304      *
305      * <p>To avoid changes that will be never reflected,
306      * the class is frozen to be unmodifiable if it is loaded or
307      * written out.  This method should be called only in a case
308      * that the class will be reloaded or written out later again.
309      *
310      * <p>If <code>defrost()</code> will be called later, pruning
311      * must be disallowed in advance.
312      *
313      * @see #isFrozen()
314      * @see #stopPruning(boolean)
315      * @see #detach()
316      */
defrost()317     public void defrost() {
318         throw new RuntimeException("cannot defrost " + getName());
319     }
320 
321     /**
322      * Returns <code>true</code> if this object represents a primitive
323      * Java type: boolean, byte, char, short, int, long, float, double,
324      * or void.
325      */
isPrimitive()326     public boolean isPrimitive() { return false; }
327 
328     /**
329      * Returns <code>true</code> if this object represents an array type.
330      */
isArray()331     public boolean isArray() {
332         return false;
333     }
334 
335     /**
336      * If this object represents an array, this method returns the component
337      * type of the array.  Otherwise, it returns <code>null</code>.
338      */
getComponentType()339     public CtClass getComponentType() throws NotFoundException {
340         return null;
341     }
342 
343     /**
344      * Returns <code>true</code> if this class extends or implements
345      * <code>clazz</code>.  It also returns <code>true</code> if
346      * this class is the same as <code>clazz</code>.
347      */
subtypeOf(CtClass clazz)348     public boolean subtypeOf(CtClass clazz) throws NotFoundException {
349         return this == clazz || getName().equals(clazz.getName());
350     }
351 
352     /**
353      * Obtains the fully-qualified name of the class.
354      */
getName()355     public String getName() { return qualifiedName; }
356 
357     /**
358      * Obtains the not-qualified class name.
359      */
getSimpleName()360     public final String getSimpleName() {
361         String qname = qualifiedName;
362         int index = qname.lastIndexOf('.');
363         if (index < 0)
364             return qname;
365         return qname.substring(index + 1);
366     }
367 
368     /**
369      * Obtains the package name.  It may be <code>null</code>.
370      */
getPackageName()371     public final String getPackageName() {
372         String qname = qualifiedName;
373         int index = qname.lastIndexOf('.');
374         if (index < 0)
375             return null;
376         return qname.substring(0, index);
377     }
378 
379     /**
380      * Sets the class name
381      *
382      * @param name      fully-qualified name
383      */
setName(String name)384     public void setName(String name) {
385         checkModify();
386         if (name != null)
387             qualifiedName = name;
388     }
389 
390     /**
391      * Returns the generic signature of the class.
392      *
393      * <p>The generics of Java is implemented by the erasure technique.
394      * After compilation, all type parameters are dropped off from the
395      * main part of a class file.  However, for reflection, the type
396      * parameters are encoded into generic signatures and attached
397      * to a class file.
398      *
399      * @return null if the generic signature is not included.
400      * @see javassist.bytecode.SignatureAttribute#toClassSignature(String)
401      * @see CtMember#getGenericSignature()
402      * @since 3.17
403      */
getGenericSignature()404     public String getGenericSignature() { return null; }
405 
406     /**
407      * Sets the generic signature of the class.
408      *
409      * <p>The generics of Java is implemented by the erasure technique.
410      * After compilation, all type parameters are dropped off from the
411      * main part of a class file.  However, for reflection, the type
412      * parameters must be encoded into generic signatures and attached
413      * to a class file.
414      *
415      * <p>For example,
416      *
417      * <pre>class List&lt;T&gt; {
418      *     T value;
419      *     T get() { return value; }
420      *     void set(T v) { value = v; }
421      * }
422      * </pre>
423      *
424      * <p>this class is generated by the following code:
425      *
426      * <pre>
427      * ClassPool pool = ClassPool.getDefault();
428      * CtClass cc = pool.makeClass("List");
429      * CtClass objectClass = pool.get(CtClass.javaLangObject);
430      * ClassSignature cs = new ClassSignature(
431      *                         new TypeParameter[] { new TypeParameter("T") });
432      * cc.setGenericSignature(cs.encode());    // &lt;T:Ljava/lang/Object;&gt;Ljava/lang/Object;
433      *
434      * CtField f = new CtField(objClass, "value", cc);
435      * TypeVariable tvar = new TypeVariable("T");
436      * f.setGenericSignature(tvar.encode());   // TT;
437      * cc.addField(f);
438      *
439      * CtMethod m = CtNewMethod.make("public Object get(){return value;}", cc);
440      * MethodSignature ms = new MethodSignature(null, null, tvar, null);
441      * m.setGenericSignature(ms.encode());     // ()TT;
442      * cc.addMethod(m);
443      *
444      * CtMethod m2 = CtNewMethod.make("public void set(Object v){value = v;}", cc);
445      * MethodSignature ms2 = new MethodSignature(null, new Type[] { tvar },
446      *                                           new BaseType("void"), null);
447      * m2.setGenericSignature(ms2.encode());   // (TT;)V;
448      * cc.addMethod(m2);
449      *
450      * cc.writeFile();
451      * </pre>
452      *
453      * <p>The generated class file is equivalent to the following:
454      *
455      * <pre>class List {
456      *     Object value;
457      *     Object get() { return value; }
458      *     void set(Object v) { value = v; }
459      * }</pre>
460      *
461      * <p>but it includes generic signatures for the class, the field,
462      * and the methods so that the type variable <code>T</code> can be
463      * accessible through reflection.
464      *
465      * <p><code>MethodSignature</code> is a utility class.  You can directly
466      * pass the signature string to the <code>setGenericSignature</code> method.
467      * For the specification of the signatures, see Section 4.7.9.1 <i>Signatures</i>
468      * of The Java Virtual Machine Specification (Java SE 8).
469      *
470      * @param sig       a generic signature.
471      * @see javassist.bytecode.SignatureAttribute.ClassSignature#encode()
472      * @see javassist.bytecode.SignatureAttribute.MethodSignature#encode()
473      * @see CtMember#setGenericSignature(String)
474      * @since 3.17
475      */
setGenericSignature(String sig)476     public void setGenericSignature(String sig) { checkModify(); }
477 
478     /**
479      * Substitutes <code>newName</code> for all occurrences of a class
480      * name <code>oldName</code> in the class file.
481      *
482      * @param oldName           replaced class name
483      * @param newName           substituted class name
484      */
replaceClassName(String oldName, String newName)485     public void replaceClassName(String oldName, String newName) {
486         checkModify();
487     }
488 
489     /**
490      * Changes class names appearing in the class file according to the
491      * given <code>map</code>.
492      *
493      * <p>All the class names appearing in the class file are tested
494      * with <code>map</code> to determine whether each class name is
495      * replaced or not.  Thus this method can be used for collecting
496      * all the class names in the class file.  To do that, first define
497      * a subclass of <code>ClassMap</code> so that <code>get()</code>
498      * records all the given parameters.  Then, make an instance of
499      * that subclass as an empty hash-table.  Finally, pass that instance
500      * to this method.  After this method finishes, that instance would
501      * contain all the class names appearing in the class file.
502      *
503      * @param map       the hashtable associating replaced class names
504      *                  with substituted names.
505      */
replaceClassName(ClassMap map)506     public void replaceClassName(ClassMap map) {
507         checkModify();
508     }
509 
510     /**
511      * Returns a collection of the names of all the classes
512      * referenced in this class.
513      * That collection includes the name of this class.
514      *
515      * <p>This method may return <code>null</code>.
516      *
517      * @return a <code>Collection&lt;String&gt;</code> object.
518      */
getRefClasses()519     public synchronized Collection<String> getRefClasses() {
520         ClassFile cf = getClassFile2();
521         if (cf != null) {
522             ClassMap cm = new ClassMap() {
523                 /** default serialVersionUID */
524                 private static final long serialVersionUID = 1L;
525                 @Override
526                 public String put(String oldname, String newname) {
527                     return put0(oldname, newname);
528                 }
529                 @Override
530                 public String get(Object jvmClassName) {
531                     String n = toJavaName((String)jvmClassName);
532                     put0(n, n);
533                     return null;
534                 }
535 
536                 @Override
537                 public void fix(String name) {}
538             };
539             cf.getRefClasses(cm);
540             return cm.values();
541         }
542         return null;
543     }
544 
545     /**
546      * Determines whether this object represents a class or an interface.
547      * It returns <code>true</code> if this object represents an interface.
548      */
isInterface()549     public boolean isInterface() {
550         return false;
551     }
552 
553     /**
554      * Determines whether this object represents an annotation type.
555      * It returns <code>true</code> if this object represents an annotation type.
556      *
557      * @since 3.2
558      */
isAnnotation()559     public boolean isAnnotation() {
560         return false;
561     }
562 
563     /**
564      * Determines whether this object represents an enum.
565      * It returns <code>true</code> if this object represents an enum.
566      *
567      * @since 3.2
568      */
isEnum()569     public boolean isEnum() {
570         return false;
571     }
572 
573     /**
574      * Returns the modifiers for this class, encoded in an integer.
575      * For decoding, use <code>javassist.Modifier</code>.
576      *
577      * <p>If the class is a static nested class (a.k.a. static inner class),
578      * the returned modifiers include <code>Modifier.STATIC</code>.
579      *
580      * @see Modifier
581      */
getModifiers()582     public int getModifiers() {
583         return 0;
584     }
585 
586     /**
587      * Returns true if the class has the specified annotation type.
588      *
589      * @param annotationType the annotation type.
590      * @return <code>true</code> if the annotation is found, otherwise <code>false</code>.
591      * @since 3.11
592      */
hasAnnotation(Class<?> annotationType)593     public boolean hasAnnotation(Class<?> annotationType) {
594         return hasAnnotation(annotationType.getName());
595     }
596 
597     /**
598      * Returns true if the class has the specified annotation type.
599      *
600      * @param annotationTypeName the name of annotation type.
601      * @return <code>true</code> if the annotation is found, otherwise <code>false</code>.
602      * @since 3.21
603      */
hasAnnotation(String annotationTypeName)604     public boolean hasAnnotation(String annotationTypeName) {
605         return false;
606     }
607 
608     /**
609      * Returns the annotation if the class has the specified annotation type.
610      * For example, if an annotation <code>@Author</code> is associated
611      * with this class, an <code>Author</code> object is returned.
612      * The member values can be obtained by calling methods on
613      * the <code>Author</code> object.
614      *
615      * @param clz the annotation type.
616      * @return the annotation if found, otherwise <code>null</code>.
617      * @since 3.11
618      */
getAnnotation(Class<?> clz)619     public Object getAnnotation(Class<?> clz) throws ClassNotFoundException {
620         return null;
621     }
622 
623     /**
624      * Returns the annotations associated with this class.
625      * For example, if an annotation <code>@Author</code> is associated
626      * with this class, the returned array contains an <code>Author</code>
627      * object.  The member values can be obtained by calling methods on
628      * the <code>Author</code> object.
629      *
630      * @return an array of annotation-type objects.
631      * @see CtMember#getAnnotations()
632      * @since 3.1
633      */
getAnnotations()634     public Object[] getAnnotations() throws ClassNotFoundException {
635         return new Object[0];
636     }
637 
638     /**
639      * Returns the annotations associated with this class.
640      * This method is equivalent to <code>getAnnotations()</code>
641      * except that, if any annotations are not on the classpath,
642      * they are not included in the returned array.
643      *
644      * @return an array of annotation-type objects.
645      * @see #getAnnotations()
646      * @see CtMember#getAvailableAnnotations()
647      * @since 3.3
648      */
getAvailableAnnotations()649     public Object[] getAvailableAnnotations(){
650        return new Object[0];
651     }
652 
653     /**
654      * Returns an array of nested classes declared in the class.
655      * Nested classes are inner classes, anonymous classes, local classes,
656      * and static nested classes.  This simply calls <code>getNestedClasses()</code>.
657      *
658      * @see #getNestedClasses()
659      * @since 3.15
660      */
getDeclaredClasses()661     public CtClass[] getDeclaredClasses() throws NotFoundException {
662         return getNestedClasses();
663     }
664 
665     /**
666      * Returns an array of nested classes declared in the class.
667      * Nested classes are inner classes, anonymous classes, local classes,
668      * and static nested classes.
669      *
670      * @since 3.2
671      */
getNestedClasses()672     public CtClass[] getNestedClasses() throws NotFoundException {
673         return new CtClass[0];
674     }
675 
676     /**
677      * Sets the modifiers.
678      *
679      * <p>If the class is a nested class, this method also modifies
680      * the class declaring that nested class (i.e. the enclosing
681      * class is modified).
682      *
683      * @param mod       modifiers encoded by
684      *                  <code>javassist.Modifier</code>
685      * @see Modifier
686      */
setModifiers(int mod)687     public void setModifiers(int mod) {
688         checkModify();
689     }
690 
691     /**
692      * Determines whether the class directly or indirectly extends
693      * the given class.  If this class extends a class A and
694      * the class A extends a class B, then subclassof(B) returns true.
695      *
696      * <p>This method returns true if the given class is identical to
697      * the class represented by this object.
698      */
subclassOf(CtClass superclass)699     public boolean subclassOf(CtClass superclass) {
700         return false;
701     }
702 
703     /**
704      * Obtains the class object representing the superclass of the
705      * class.
706      * It returns null if this object represents the
707      * <code>java.lang.Object</code> class and thus it does not have
708      * the super class.
709      *
710      * <p>If this object represents an interface, this method
711      * always returns the <code>java.lang.Object</code> class.
712      * To obtain the super interfaces
713      * extended by that interface, call <code>getInterfaces()</code>.
714      */
getSuperclass()715     public CtClass getSuperclass() throws NotFoundException {
716         return null;
717     }
718 
719     /**
720      * Changes a super class unless this object represents an interface.
721      * The new super class must be compatible with the old one; for example,
722      * it should inherit from the old super class.
723      *
724      * <p>If this object represents an interface, this method is equivalent
725      * to <code>addInterface()</code>; it appends <code>clazz</code> to
726      * the list of the super interfaces extended by that interface.
727      * Note that an interface can extend multiple super interfaces.
728      *
729      * @see #replaceClassName(String, String)
730      * @see #replaceClassName(ClassMap)
731      */
setSuperclass(CtClass clazz)732     public void setSuperclass(CtClass clazz) throws CannotCompileException {
733         checkModify();
734     }
735 
736     /**
737      * Obtains the class objects representing the interfaces implemented
738      * by the class or, if this object represents an interface, the interfaces
739      * extended by that interface.
740      */
getInterfaces()741     public CtClass[] getInterfaces() throws NotFoundException {
742         return new CtClass[0];
743     }
744 
745     /**
746      * Sets implemented interfaces.  If this object represents an interface,
747      * this method sets the interfaces extended by that interface.
748      *
749      * @param list              a list of the <code>CtClass</code> objects
750      *                          representing interfaces, or
751      *                          <code>null</code> if the class implements
752      *                          no interfaces.
753      */
setInterfaces(CtClass[] list)754     public void setInterfaces(CtClass[] list) {
755         checkModify();
756     }
757 
758     /**
759      * Adds an interface.
760      *
761      * @param anInterface       the added interface.
762      */
addInterface(CtClass anInterface)763     public void addInterface(CtClass anInterface) {
764         checkModify();
765     }
766 
767     /**
768      * If this class is a member class or interface of another class,
769      * then the class enclosing this class is returned.
770      *
771      * @return null if this class is a top-level class or an anonymous class.
772      */
getDeclaringClass()773     public CtClass getDeclaringClass() throws NotFoundException {
774         return null;
775     }
776 
777     /**
778      * Returns the immediately enclosing method of this class.
779      * This method works only with JDK 1.5 or later.
780      *
781      * @return null if this class is not a local class or an anonymous
782      * class.
783      * @deprecated The enclosing method might be a constructor.
784      *             Use {@link #getEnclosingBehavior()}.
785      * @see #getEnclosingBehavior()
786      */
787     @Deprecated
getEnclosingMethod()788     public final CtMethod getEnclosingMethod() throws NotFoundException {
789         CtBehavior b = getEnclosingBehavior();
790         if (b == null)
791             return null;
792         else if (b instanceof CtMethod)
793             return (CtMethod)b;
794         else
795             throw new NotFoundException(b.getLongName() + " is enclosing " + getName());
796     }
797 
798     /**
799      * Returns the immediately enclosing method of this class.
800      * It might be not a method but a constructor.
801      * This method works only with JDK 1.5 or later.
802      *
803      * @return null if this class is not a local class or an anonymous
804      * class.
805      */
getEnclosingBehavior()806     public CtBehavior getEnclosingBehavior() throws NotFoundException {
807         return null;
808     }
809 
810     /**
811      * Makes a new public nested class.  If this method is called,
812      * the <code>CtClass</code>, which encloses the nested class, is modified
813      * since a class file includes a list of nested classes.
814      *
815      * <p>The current implementation only supports a static nested class.
816      * <code>isStatic</code> must be true.
817      *
818      * @param name          the simple name of the nested class.
819      * @param isStatic      true if the nested class is static.
820      */
makeNestedClass(String name, boolean isStatic)821     public CtClass makeNestedClass(String name, boolean isStatic) {
822         throw new RuntimeException(getName() + " is not a class");
823     }
824 
825     /**
826      * Returns an array containing <code>CtField</code> objects
827      * representing all the non-private fields of the class.
828      * That array includes non-private fields inherited from the
829      * superclasses.
830      */
getFields()831     public CtField[] getFields() { return new CtField[0]; }
832 
833     /**
834      * Returns the field with the specified name.  The returned field
835      * may be a private field declared in a super class or interface.
836      */
getField(String name)837     public CtField getField(String name) throws NotFoundException {
838         return getField(name, null);
839     }
840 
841     /**
842      * Returns the field with the specified name and type.  The returned field
843      * may be a private field declared in a super class or interface.
844      * Unlike Java, the JVM allows a class to have
845      * multiple fields with the same name but different types.
846      *
847      * @param name      the field name.
848      * @param desc      the type descriptor of the field.  It is available by
849      *                  {@link CtField#getSignature()}.
850      * @see CtField#getSignature()
851      */
getField(String name, String desc)852     public CtField getField(String name, String desc) throws NotFoundException {
853         throw new NotFoundException(name);
854     }
855 
856     /**
857      * @return null     if the specified field is not found.
858      */
getField2(String name, String desc)859     CtField getField2(String name, String desc) { return null; }
860 
861     /**
862      * Gets all the fields declared in the class.  The inherited fields
863      * are not included.
864      *
865      * <p>Note: the result does not include inherited fields.
866      */
getDeclaredFields()867     public CtField[] getDeclaredFields() { return new CtField[0]; }
868 
869     /**
870      * Retrieves the field with the specified name among the fields
871      * declared in the class.
872      *
873      * <p>Note: this method does not search the super classes.
874      */
getDeclaredField(String name)875     public CtField getDeclaredField(String name) throws NotFoundException {
876         throw new NotFoundException(name);
877     }
878 
879     /**
880      * Retrieves the field with the specified name and type among the fields
881      * declared in the class.  Unlike Java, the JVM allows a class to have
882      * multiple fields with the same name but different types.
883      *
884      * <p>Note: this method does not search the super classes.
885      *
886      * @param name      the field name.
887      * @param desc      the type descriptor of the field.  It is available by
888      *                  {@link CtField#getSignature()}.
889      * @see CtField#getSignature()
890      */
getDeclaredField(String name, String desc)891     public CtField getDeclaredField(String name, String desc) throws NotFoundException {
892         throw new NotFoundException(name);
893     }
894 
895     /**
896      * Gets all the constructors and methods declared in the class.
897      */
getDeclaredBehaviors()898     public CtBehavior[] getDeclaredBehaviors() {
899         return new CtBehavior[0];
900     }
901 
902     /**
903      * Returns an array containing <code>CtConstructor</code> objects
904      * representing all the non-private constructors of the class.
905      */
getConstructors()906     public CtConstructor[] getConstructors() {
907         return new CtConstructor[0];
908     }
909 
910     /**
911      * Returns the constructor with the given signature,
912      * which is represented by a character string
913      * called method descriptor.
914      * For details of the method descriptor, see the JVM specification
915      * or <code>javassist.bytecode.Descriptor</code>.
916      *
917      * @param desc      method descriptor
918      * @see javassist.bytecode.Descriptor
919      */
getConstructor(String desc)920     public CtConstructor getConstructor(String desc)
921         throws NotFoundException
922     {
923         throw new NotFoundException("no such constructor");
924     }
925 
926     /**
927      * Gets all the constructors declared in the class.
928      *
929      * @see javassist.CtConstructor
930      */
getDeclaredConstructors()931     public CtConstructor[] getDeclaredConstructors() {
932         return new CtConstructor[0];
933     }
934 
935     /**
936      * Returns a constructor receiving the specified parameters.
937      *
938      * @param params    parameter types.
939      */
getDeclaredConstructor(CtClass[] params)940     public CtConstructor getDeclaredConstructor(CtClass[] params)
941         throws NotFoundException
942     {
943         String desc = Descriptor.ofConstructor(params);
944         return getConstructor(desc);
945     }
946 
947     /**
948      * Gets the class initializer (static constructor)
949      * declared in the class.
950      * This method returns <code>null</code> if
951      * no class initializer is not declared.
952      *
953      * @see #makeClassInitializer()
954      * @see javassist.CtConstructor
955      */
getClassInitializer()956     public CtConstructor getClassInitializer() {
957         return null;
958     }
959 
960     /**
961      * Returns an array containing <code>CtMethod</code> objects
962      * representing all the non-private methods of the class.
963      * That array includes non-private methods inherited from the
964      * superclasses.
965      */
getMethods()966     public CtMethod[] getMethods() {
967         return new CtMethod[0];
968     }
969 
970     /**
971      * Returns the method with the given name and signature.
972      * The returned method may be declared in a super class.
973      * The method signature is represented by a character string
974      * called method descriptor,
975      * which is defined in the JVM specification.
976      *
977      * @param name      method name
978      * @param desc      method descriptor
979      * @see CtBehavior#getSignature()
980      * @see javassist.bytecode.Descriptor
981      */
getMethod(String name, String desc)982     public CtMethod getMethod(String name, String desc)
983         throws NotFoundException
984     {
985         throw new NotFoundException(name);
986     }
987 
988     /**
989      * Gets all methods declared in the class.  The inherited methods
990      * are not included.
991      *
992      * @see javassist.CtMethod
993      */
getDeclaredMethods()994     public CtMethod[] getDeclaredMethods() {
995         return new CtMethod[0];
996     }
997 
998     /**
999      * Retrieves the method with the specified name and parameter types
1000      * among the methods declared in the class.
1001      *
1002      * <p>Note: this method does not search the superclasses.
1003      *
1004      * @param name              method name
1005      * @param params            parameter types
1006      * @see javassist.CtMethod
1007      */
getDeclaredMethod(String name, CtClass[] params)1008     public CtMethod getDeclaredMethod(String name, CtClass[] params)
1009         throws NotFoundException
1010     {
1011         throw new NotFoundException(name);
1012     }
1013 
1014     /**
1015      * Retrieves methods with the specified name among the methods
1016      * declared in the class.  Multiple methods with different parameters
1017      * may be returned.
1018      *
1019      * <p>Note: this method does not search the superclasses.</p>
1020      *
1021      * @param name      method name.
1022      * @since 3.19
1023      */
getDeclaredMethods(String name)1024     public CtMethod[] getDeclaredMethods(String name) throws NotFoundException {
1025         throw new NotFoundException(name);
1026     }
1027 
1028     /**
1029      * Retrieves the method with the specified name among the methods
1030      * declared in the class.  If there are multiple methods with
1031      * the specified name, then this method returns one of them.
1032      *
1033      * <p>Note: this method does not search the superclasses.
1034      *
1035      * @see javassist.CtMethod
1036      */
getDeclaredMethod(String name)1037     public CtMethod getDeclaredMethod(String name) throws NotFoundException {
1038         throw new NotFoundException(name);
1039     }
1040 
1041     /**
1042      * Makes an empty class initializer (static constructor).
1043      * If the class already includes a class initializer,
1044      * this method returns it.
1045      *
1046      * @see #getClassInitializer()
1047      */
makeClassInitializer()1048     public CtConstructor makeClassInitializer()
1049         throws CannotCompileException
1050     {
1051         throw new CannotCompileException("not a class");
1052     }
1053 
1054     /**
1055      * Adds a constructor.  To add a class initializer (static constructor),
1056      * call <code>makeClassInitializer()</code>.
1057      *
1058      * @see #makeClassInitializer()
1059      */
addConstructor(CtConstructor c)1060     public void addConstructor(CtConstructor c)
1061         throws CannotCompileException
1062     {
1063         checkModify();
1064     }
1065 
1066     /**
1067      * Removes a constructor declared in this class.
1068      *
1069      * @param c     removed constructor.
1070      * @throws NotFoundException   if the constructor is not found.
1071      */
removeConstructor(CtConstructor c)1072     public void removeConstructor(CtConstructor c) throws NotFoundException {
1073         checkModify();
1074     }
1075 
1076     /**
1077      * Adds a method.
1078      */
addMethod(CtMethod m)1079     public void addMethod(CtMethod m) throws CannotCompileException {
1080         checkModify();
1081     }
1082 
1083     /**
1084      * Removes a method declared in this class.
1085      *
1086      * @param m     removed method.
1087      * @throws NotFoundException   if the method is not found.
1088      */
removeMethod(CtMethod m)1089     public void removeMethod(CtMethod m) throws NotFoundException {
1090         checkModify();
1091      }
1092 
1093     /**
1094      * Adds a field.
1095      *
1096      * <p>The <code>CtField</code> belonging to another
1097      * <code>CtClass</code> cannot be directly added to this class.
1098      * Only a field created for this class can be added.
1099      *
1100      * @see javassist.CtField#CtField(CtField,CtClass)
1101      */
addField(CtField f)1102     public void addField(CtField f) throws CannotCompileException {
1103         addField(f, (CtField.Initializer)null);
1104     }
1105 
1106     /**
1107      * Adds a field with an initial value.
1108      *
1109      * <p>The <code>CtField</code> belonging to another
1110      * <code>CtClass</code> cannot be directly added to this class.
1111      * Only a field created for this class can be added.
1112      *
1113      * <p>The initial value is given as an expression written in Java.
1114      * Any regular Java expression can be used for specifying the initial
1115      * value.  The followings are examples.
1116      *
1117      * <pre>
1118      * cc.addField(f, "0")               // the initial value is 0.
1119      * cc.addField(f, "i + 1")           // i + 1.
1120      * cc.addField(f, "new Point()");    // a Point object.
1121      * </pre>
1122      *
1123      * <p>Here, the type of variable <code>cc</code> is <code>CtClass</code>.
1124      * The type of <code>f</code> is <code>CtField</code>.
1125      *
1126      * <p>Note: do not change the modifier of the field
1127      * (in particular, do not add or remove <code>static</code>
1128      * to/from the modifier)
1129      * after it is added to the class by <code>addField()</code>.
1130      *
1131      * @param init      an expression for the initial value.
1132      *
1133      * @see javassist.CtField.Initializer#byExpr(String)
1134      * @see javassist.CtField#CtField(CtField,CtClass)
1135      */
addField(CtField f, String init)1136     public void addField(CtField f, String init)
1137         throws CannotCompileException
1138     {
1139         checkModify();
1140     }
1141 
1142     /**
1143      * Adds a field with an initial value.
1144      *
1145      * <p>The <code>CtField</code> belonging to another
1146      * <code>CtClass</code> cannot be directly added to this class.
1147      * Only a field created for this class can be added.
1148      *
1149      * <p>For example,
1150      *
1151      * <pre>
1152      * CtClass cc = ...;
1153      * addField(new CtField(CtClass.intType, "i", cc),
1154      *          CtField.Initializer.constant(1));
1155      * </pre>
1156      *
1157      * <p>This code adds an <code>int</code> field named "i".  The
1158      * initial value of this field is 1.
1159      *
1160      * @param init      specifies the initial value of the field.
1161      *
1162      * @see javassist.CtField#CtField(CtField,CtClass)
1163      */
addField(CtField f, CtField.Initializer init)1164     public void addField(CtField f, CtField.Initializer init)
1165         throws CannotCompileException
1166     {
1167         checkModify();
1168     }
1169 
1170     /**
1171      * Removes a field declared in this class.
1172      *
1173      * @param f     removed field.
1174      * @throws NotFoundException   if the field is not found.
1175      */
removeField(CtField f)1176     public void removeField(CtField f) throws NotFoundException {
1177         checkModify();
1178     }
1179 
1180     /**
1181      * Obtains an attribute with the given name.
1182      * If that attribute is not found in the class file, this
1183      * method returns null.
1184      *
1185      * <p>This is a convenient method mainly for obtaining
1186      * a user-defined attribute.  For dealing with attributes, see the
1187      * <code>javassist.bytecode</code> package.  For example, the following
1188      * expression returns all the attributes of a class file.
1189      *
1190      * <pre>
1191      * getClassFile().getAttributes()
1192      * </pre>
1193      *
1194      * @param name              attribute name
1195      * @see javassist.bytecode.AttributeInfo
1196      */
getAttribute(String name)1197     public byte[] getAttribute(String name) {
1198         return null;
1199     }
1200 
1201     /**
1202      * Adds a named attribute.
1203      * An arbitrary data (smaller than 64Kb) can be saved in the class
1204      * file.  Some attribute name are reserved by the JVM.
1205      * The attributes with the non-reserved names are ignored when a
1206      * class file is loaded into the JVM.
1207      * If there is already an attribute with
1208      * the same name, this method substitutes the new one for it.
1209      *
1210      * <p>This is a convenient method mainly for adding
1211      * a user-defined attribute.  For dealing with attributes, see the
1212      * <code>javassist.bytecode</code> package.  For example, the following
1213      * expression adds an attribute <code>info</code> to a class file.
1214      *
1215      * <pre>
1216      * getClassFile().addAttribute(info)
1217      * </pre>
1218      *
1219      * @param name      attribute name
1220      * @param data      attribute value
1221      * @see javassist.bytecode.AttributeInfo
1222      */
setAttribute(String name, byte[] data)1223     public void setAttribute(String name, byte[] data) {
1224         checkModify();
1225     }
1226 
1227     /**
1228      * Applies the given converter to all methods and constructors
1229      * declared in the class.  This method calls <code>instrument()</code>
1230      * on every <code>CtMethod</code> and <code>CtConstructor</code> object
1231      * in the class.
1232      *
1233      * @param converter         specifies how to modify.
1234      */
instrument(CodeConverter converter)1235     public void instrument(CodeConverter converter)
1236         throws CannotCompileException
1237     {
1238         checkModify();
1239     }
1240 
1241     /**
1242      * Modifies the bodies of all methods and constructors
1243      * declared in the class.  This method calls <code>instrument()</code>
1244      * on every <code>CtMethod</code> and <code>CtConstructor</code> object
1245      * in the class.
1246      *
1247      * @param editor            specifies how to modify.
1248      */
instrument(ExprEditor editor)1249     public void instrument(ExprEditor editor)
1250         throws CannotCompileException
1251     {
1252         checkModify();
1253     }
1254 
1255     /**
1256      * Converts this class to a <code>java.lang.Class</code> object.
1257      * Once this method is called, further modifications are not
1258      * allowed any more.
1259      * To load the class, this method uses the context class loader
1260      * of the current thread.  If the program is running on some application
1261      * server, the context class loader might be inappropriate to load the
1262      * class.
1263      *
1264      * <p><b>Warning:</b> In Java 11 or later, the call to this method will
1265      * print a warning message:</p>
1266      * <blockquote><pre>
1267      * WARNING: An illegal reflective access operation has occurred
1268      * WARNING: Illegal reflective access by javassist.util.proxy.SecurityActions$3 ...
1269      * WARNING: Please consider reporting this to the maintainers of javassist.util.proxy.SecurityActions$3
1270      * WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations
1271      * WARNING: All illegal access operations will be denied in a future release
1272      * </pre></blockquote>
1273      * <p>To avoid this message, use {@link #toClass(Class)}
1274      * or {@link #toClass(java.lang.invoke.MethodHandles.Lookup)}.
1275      * {@link #toClass()} will be unavailable in a future release.
1276      * </p>
1277      *
1278      * <p><b>Warning:</b> A Class object returned by this method may not
1279      * work with a security manager or a signed jar file because a
1280      * protection domain is not specified.</p>
1281      *
1282      * <p>Note: this method calls <code>toClass()</code>
1283      * in <code>ClassPool</code>.</p>
1284      *
1285      * @see #toClass(java.lang.invoke.MethodHandles.Lookup)
1286      * @see #toClass(Class)
1287      * @see ClassPool#toClass(CtClass)
1288      */
toClass()1289     public Class<?> toClass() throws CannotCompileException {
1290         return getClassPool().toClass(this);
1291     }
1292 
1293     /**
1294      * Converts this class to a <code>java.lang.Class</code> object.
1295      * Once this method is called, further modifications are not
1296      * allowed any more.
1297      *
1298      * <p>This method is provided for convenience.  You should use
1299      * {@code toClass(Lookup)} for better compatibility with the
1300      * module system.
1301      *
1302      * <p>Note: this method calls <code>toClass()</code>
1303      * in <code>ClassPool</code>.
1304      *
1305      * <p><b>Warning:</b> A Class object returned by this method may not
1306      * work with a security manager or a signed jar file because a
1307      * protection domain is not specified.
1308      *
1309      * @param neighbor    A class belonging to the same package that this
1310      *                    class belongs to.  It is used to load the class.
1311      * @see ClassPool#toClass(CtClass,Class)
1312      * @see #toClass(java.lang.invoke.MethodHandles.Lookup)
1313      * @since 3.24
1314      */
toClass(Class<?> neighbor)1315     public Class<?> toClass(Class<?> neighbor) throws CannotCompileException
1316     {
1317         return getClassPool().toClass(this, neighbor);
1318     }
1319 
1320     /**
1321      * Converts this class to a <code>java.lang.Class</code> object.
1322      * Once this method is called, further modifications are not
1323      * allowed any more.
1324      *
1325      * <p>This method is provided for convenience.  If you need more
1326      * complex functionality, you should write your own class loader.
1327      *
1328      * <p>Note: this method calls <code>toClass()</code>
1329      * in <code>ClassPool</code>.
1330      *
1331      * <p><b>Warning:</b> A Class object returned by this method may not
1332      * work with a security manager or a signed jar file because a
1333      * protection domain is not specified.
1334      *
1335      * @param lookup    used when loading the class.  It has to have
1336      *                  an access right to define a new class.
1337      * @see ClassPool#toClass(CtClass,java.lang.invoke.MethodHandles.Lookup)
1338      * @since 3.24
1339      */
toClass(java.lang.invoke.MethodHandles.Lookup lookup)1340     public Class<?> toClass(java.lang.invoke.MethodHandles.Lookup lookup)
1341         throws CannotCompileException
1342     {
1343         return getClassPool().toClass(this, lookup);
1344     }
1345 
1346     /**
1347      * Converts this class to a <code>java.lang.Class</code> object.
1348      * Once this method is called, further modifications are not allowed
1349      * any more.
1350      *
1351      * <p>The class file represented by this <code>CtClass</code> is
1352      * loaded by the given class loader to construct a
1353      * <code>java.lang.Class</code> object.  Since a private method
1354      * on the class loader is invoked through the reflection API,
1355      * the caller must have permissions to do that.
1356      *
1357      * <p>An easy way to obtain <code>ProtectionDomain</code> object is
1358      * to call <code>getProtectionDomain()</code>
1359      * in <code>java.lang.Class</code>.  It returns the domain that
1360      * the class belongs to.
1361      *
1362      * <p>This method is provided for convenience.  If you need more
1363      * complex functionality, you should write your own class loader.
1364      *
1365      * <p>Note: this method calls <code>toClass()</code>
1366      * in <code>ClassPool</code>.
1367      *
1368      * @param loader        the class loader used to load this class.
1369      *                      If it is null, the class loader returned by
1370      *                      {@link ClassPool#getClassLoader()} is used.
1371      * @param domain        the protection domain that the class belongs to.
1372      *                      If it is null, the default domain created
1373      *                      by <code>java.lang.ClassLoader</code> is used.
1374      * @see ClassPool#toClass(CtClass,java.lang.ClassLoader)
1375      * @since 3.3
1376      */
toClass(ClassLoader loader, ProtectionDomain domain)1377     public Class<?> toClass(ClassLoader loader, ProtectionDomain domain)
1378         throws CannotCompileException
1379     {
1380         ClassPool cp = getClassPool();
1381         if (loader == null)
1382             loader = cp.getClassLoader();
1383 
1384         return cp.toClass(this, null, loader, domain);
1385     }
1386 
1387     /**
1388      * Converts this class to a <code>java.lang.Class</code> object.
1389      *
1390      * <p><b>Warning:</b> A Class object returned by this method may not
1391      * work with a security manager or a signed jar file because a
1392      * protection domain is not specified.
1393      *
1394      * @deprecated      Replaced by {@link #toClass(ClassLoader,ProtectionDomain)}
1395      */
1396     @Deprecated
toClass(ClassLoader loader)1397     public final Class<?> toClass(ClassLoader loader)
1398         throws CannotCompileException
1399     {
1400         return getClassPool().toClass(this, null, loader, null);
1401     }
1402 
1403     /**
1404      * Removes this <code>CtClass</code> object from the
1405      * <code>ClassPool</code>.
1406      * After this method is called, any method cannot be called on the
1407      * removed <code>CtClass</code> object.
1408      *
1409      * <p>If <code>get()</code> in <code>ClassPool</code> is called
1410      * with the name of the removed method,
1411      * the <code>ClassPool</code> will read the class file again
1412      * and constructs another <code>CtClass</code> object representing
1413      * the same class.
1414      */
detach()1415     public void detach() {
1416         ClassPool cp = getClassPool();
1417         CtClass obj = cp.removeCached(getName());
1418         if (obj != this)
1419             cp.cacheCtClass(getName(), obj, false);
1420     }
1421 
1422     /**
1423      * Disallows (or allows) automatically pruning this <code>CtClass</code>
1424      * object.
1425      *
1426      * <p>
1427      * Javassist can automatically prune a <code>CtClass</code> object
1428      * when <code>toBytecode()</code> (or <code>toClass()</code>,
1429      * <code>writeFile()</code>) is called.
1430      * Since a <code>ClassPool</code> holds all instances of <code>CtClass</code>
1431      * even after <code>toBytecode()</code> (or <code>toClass()</code>,
1432      * <code>writeFile()</code>) is called, pruning may significantly
1433      * save memory consumption.
1434      *
1435      * <p>If <code>ClassPool.doPruning</code> is true, the automatic pruning
1436      * is on by default.  Otherwise, it is off.  The default value of
1437      * <code>ClassPool.doPruning</code> is false.
1438      *
1439      * @param stop      disallow pruning if true.  Otherwise, allow.
1440      * @return the previous status of pruning.  true if pruning is already stopped.
1441      *
1442      * @see #detach()
1443      * @see #prune()
1444      * @see ClassPool#doPruning
1445      */
stopPruning(boolean stop)1446     public boolean stopPruning(boolean stop) { return true; }
1447 
1448     /**
1449      * Discards unnecessary attributes, in particular,
1450      * <code>CodeAttribute</code>s (method bodies) of the class,
1451      * to minimize the memory footprint.
1452      * After calling this method, the class is read only.
1453      * It cannot be modified any more.
1454      * Furthermore, <code>toBytecode()</code>,
1455      * <code>writeFile()</code>, <code>toClass()</code>,
1456      * or <code>instrument()</code> cannot be called.
1457      * However, the method names and signatures in the class etc.
1458      * are still accessible.
1459      *
1460      * <p><code>toBytecode()</code>, <code>writeFile()</code>, and
1461      * <code>toClass()</code> internally call this method if
1462      * automatic pruning is on.
1463      *
1464      * <p>According to some experiments, pruning does not really reduce
1465      * memory consumption.  Only about 20%.  Since pruning takes time,
1466      * it might not pay off.  So the automatic pruning is off by default.
1467      *
1468      * @see #stopPruning(boolean)
1469      * @see #detach()
1470      * @see ClassPool#doPruning
1471      *
1472      * @see #toBytecode()
1473      * @see #toClass(Class)
1474      * @see #writeFile()
1475      * @see #instrument(CodeConverter)
1476      * @see #instrument(ExprEditor)
1477      */
prune()1478     public void prune() {}
1479 
1480     /* Called by get() in ClassPool.
1481      * CtClassType overrides this method.
1482      */
incGetCounter()1483     void incGetCounter() {}
1484 
1485     /**
1486      * If this method is called, the class file will be
1487      * rebuilt when it is finally generated by
1488      * <code>toBytecode()</code> and <code>writeFile()</code>.
1489      * For a performance reason, the symbol table of the
1490      * class file may contain unused entries, for example,
1491      * after a method or a filed is deleted.
1492      * This method
1493      * removes those unused entries.  This removal will
1494      * minimize the size of the class file.
1495      *
1496      * @since 3.8.1
1497      */
rebuildClassFile()1498     public void rebuildClassFile() {}
1499 
1500     /**
1501      * Converts this class to a class file.
1502      * Once this method is called, further modifications are not
1503      * possible any more.
1504      *
1505      * @return the contents of the class file.
1506      */
toBytecode()1507     public byte[] toBytecode() throws IOException, CannotCompileException {
1508         ByteArrayOutputStream barray = new ByteArrayOutputStream();
1509         DataOutputStream out = new DataOutputStream(barray);
1510         try {
1511             toBytecode(out);
1512         }
1513         finally {
1514             out.close();
1515         }
1516 
1517         return barray.toByteArray();
1518     }
1519 
1520     /**
1521      * Writes a class file represented by this <code>CtClass</code>
1522      * object in the current directory.
1523      * Once this method is called, further modifications are not
1524      * possible any more.
1525      *
1526      * @see #debugWriteFile()
1527      */
writeFile()1528     public void writeFile()
1529         throws NotFoundException, IOException, CannotCompileException
1530     {
1531         writeFile(".");
1532     }
1533 
1534     /**
1535      * Writes a class file represented by this <code>CtClass</code>
1536      * object on a local disk.
1537      * Once this method is called, further modifications are not
1538      * possible any more.
1539      *
1540      * @param directoryName     it must end without a directory separator.
1541      * @see #debugWriteFile(String)
1542      */
writeFile(String directoryName)1543     public void writeFile(String directoryName)
1544         throws CannotCompileException, IOException
1545     {
1546         DataOutputStream out = makeFileOutput(directoryName);
1547         try {
1548             toBytecode(out);
1549         }
1550         finally {
1551             out.close();
1552         }
1553     }
1554 
makeFileOutput(String directoryName)1555     protected DataOutputStream makeFileOutput(String directoryName) {
1556         String classname = getName();
1557         String filename = directoryName + File.separatorChar
1558             + classname.replace('.', File.separatorChar) + ".class";
1559         int pos = filename.lastIndexOf(File.separatorChar);
1560         if (pos > 0) {
1561             String dir = filename.substring(0, pos);
1562             if (!dir.equals("."))
1563                 new File(dir).mkdirs();
1564         }
1565 
1566         return new DataOutputStream(new BufferedOutputStream(
1567                                       new DelayedFileOutputStream(filename)));
1568     }
1569 
1570     /**
1571      * Writes a class file as <code>writeFile()</code> does although this
1572      * method does not prune or freeze the class after writing the class
1573      * file.  Note that, once <code>writeFile()</code> or <code>toBytecode()</code>
1574      * is called, it cannot be called again since the class is pruned and frozen.
1575      * This method would be useful for debugging.
1576      */
debugWriteFile()1577     public void debugWriteFile() {
1578         debugWriteFile(".");
1579     }
1580 
1581     /**
1582      * Writes a class file as <code>writeFile()</code> does although this
1583      * method does not prune or freeze the class after writing the class
1584      * file.  Note that, once <code>writeFile()</code> or <code>toBytecode()</code>
1585      * is called, it cannot be called again since the class is pruned and frozen.
1586      * This method would be useful for debugging.
1587      *
1588      * @param directoryName     it must end without a directory separator.
1589      */
debugWriteFile(String directoryName)1590     public void debugWriteFile(String directoryName) {
1591         try {
1592             boolean p = stopPruning(true);
1593             writeFile(directoryName);
1594             defrost();
1595             stopPruning(p);
1596         }
1597         catch (Exception e) {
1598             throw new RuntimeException(e);
1599         }
1600     }
1601 
1602     static class DelayedFileOutputStream extends OutputStream {
1603         private FileOutputStream file;
1604         private String filename;
1605 
DelayedFileOutputStream(String name)1606         DelayedFileOutputStream(String name) {
1607             file = null;
1608             filename = name;
1609         }
1610 
init()1611         private void init() throws IOException {
1612             if (file == null)
1613                 file = new FileOutputStream(filename);
1614         }
1615 
1616         @Override
write(int b)1617         public void write(int b) throws IOException {
1618             init();
1619             file.write(b);
1620         }
1621 
1622         @Override
write(byte[] b)1623         public void write(byte[] b) throws IOException {
1624             init();
1625             file.write(b);
1626         }
1627 
1628         @Override
write(byte[] b, int off, int len)1629         public void write(byte[] b, int off, int len) throws IOException {
1630             init();
1631             file.write(b, off, len);
1632 
1633         }
1634 
1635         @Override
flush()1636         public void flush() throws IOException {
1637             init();
1638             file.flush();
1639         }
1640 
1641         @Override
close()1642         public void close() throws IOException {
1643             init();
1644             file.close();
1645         }
1646     }
1647 
1648     /**
1649      * Converts this class to a class file.
1650      * Once this method is called, further modifications are not
1651      * possible any more.
1652      *
1653      * <p>This method dose not close the output stream in the end.
1654      *
1655      * @param out       the output stream that a class file is written to.
1656      */
toBytecode(DataOutputStream out)1657     public void toBytecode(DataOutputStream out)
1658         throws CannotCompileException, IOException
1659     {
1660         throw new CannotCompileException("not a class");
1661     }
1662 
1663     /**
1664      * Makes a unique member name.  This method guarantees that
1665      * the returned name is not used as a prefix of any methods
1666      * or fields visible in this class.
1667      * If the returned name is XYZ, then any method or field names
1668      * in this class do not start with XYZ.
1669      *
1670      * @param prefix        the prefix of the member name.
1671      */
makeUniqueName(String prefix)1672     public String makeUniqueName(String prefix) {
1673         throw new RuntimeException("not available in " + getName());
1674     }
1675 
1676     /* Invoked from ClassPool#compress().
1677      * This method is overridden by CtClassType.
1678      */
compress()1679     void compress() {}
1680 }
1681