| /* |
| * Copyright (c) 1996, 2010, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package java.lang.reflect; |
| |
| import sun.reflect.CallerSensitive; |
| import sun.reflect.ConstructorAccessor; |
| import sun.reflect.Reflection; |
| import sun.reflect.generics.repository.ConstructorRepository; |
| import sun.reflect.generics.factory.CoreReflectionFactory; |
| import sun.reflect.generics.factory.GenericsFactory; |
| import sun.reflect.generics.scope.ConstructorScope; |
| import java.lang.annotation.Annotation; |
| import java.util.Map; |
| import sun.reflect.annotation.AnnotationParser; |
| import java.lang.annotation.AnnotationFormatError; |
| import java.lang.reflect.Modifier; |
| |
| /** |
| * {@code Constructor} provides information about, and access to, a single |
| * constructor for a class. |
| * |
| * <p>{@code Constructor} permits widening conversions to occur when matching the |
| * actual parameters to newInstance() with the underlying |
| * constructor's formal parameters, but throws an |
| * {@code IllegalArgumentException} if a narrowing conversion would occur. |
| * |
| * @param <T> the class in which the constructor is declared |
| * |
| * @see Member |
| * @see java.lang.Class |
| * @see java.lang.Class#getConstructors() |
| * @see java.lang.Class#getConstructor(Class[]) |
| * @see java.lang.Class#getDeclaredConstructors() |
| * |
| * @author Kenneth Russell |
| * @author Nakul Saraiya |
| */ |
| public final |
| class Constructor<T> extends AccessibleObject implements |
| GenericDeclaration, |
| Member { |
| |
| private Class<T> clazz; |
| private int slot; |
| private Class<?>[] parameterTypes; |
| private Class<?>[] exceptionTypes; |
| private int modifiers; |
| // Generics and annotations support |
| private transient String signature; |
| // generic info repository; lazily initialized |
| private transient ConstructorRepository genericInfo; |
| private byte[] annotations; |
| private byte[] parameterAnnotations; |
| |
| // Generics infrastructure |
| // Accessor for factory |
| private GenericsFactory getFactory() { |
| // create scope and factory |
| return CoreReflectionFactory.make(this, ConstructorScope.make(this)); |
| } |
| |
| // Accessor for generic info repository |
| private ConstructorRepository getGenericInfo() { |
| // lazily initialize repository if necessary |
| if (genericInfo == null) { |
| // create and cache generic info repository |
| genericInfo = |
| ConstructorRepository.make(getSignature(), |
| getFactory()); |
| } |
| return genericInfo; //return cached repository |
| } |
| |
| private volatile ConstructorAccessor constructorAccessor; |
| // For sharing of ConstructorAccessors. This branching structure |
| // is currently only two levels deep (i.e., one root Constructor |
| // and potentially many Constructor objects pointing to it.) |
| private Constructor<T> root; |
| |
| /** |
| * Package-private constructor used by ReflectAccess to enable |
| * instantiation of these objects in Java code from the java.lang |
| * package via sun.reflect.LangReflectAccess. |
| */ |
| Constructor(Class<T> declaringClass, |
| Class<?>[] parameterTypes, |
| Class<?>[] checkedExceptions, |
| int modifiers, |
| int slot, |
| String signature, |
| byte[] annotations, |
| byte[] parameterAnnotations) |
| { |
| this.clazz = declaringClass; |
| this.parameterTypes = parameterTypes; |
| this.exceptionTypes = checkedExceptions; |
| this.modifiers = modifiers; |
| this.slot = slot; |
| this.signature = signature; |
| this.annotations = annotations; |
| this.parameterAnnotations = parameterAnnotations; |
| } |
| |
| /** |
| * Package-private routine (exposed to java.lang.Class via |
| * ReflectAccess) which returns a copy of this Constructor. The copy's |
| * "root" field points to this Constructor. |
| */ |
| Constructor<T> copy() { |
| // This routine enables sharing of ConstructorAccessor objects |
| // among Constructor objects which refer to the same underlying |
| // method in the VM. (All of this contortion is only necessary |
| // because of the "accessibility" bit in AccessibleObject, |
| // which implicitly requires that new java.lang.reflect |
| // objects be fabricated for each reflective call on Class |
| // objects.) |
| Constructor<T> res = new Constructor<>(clazz, |
| parameterTypes, |
| exceptionTypes, modifiers, slot, |
| signature, |
| annotations, |
| parameterAnnotations); |
| res.root = this; |
| // Might as well eagerly propagate this if already present |
| res.constructorAccessor = constructorAccessor; |
| return res; |
| } |
| |
| /** |
| * Returns the {@code Class} object representing the class that declares |
| * the constructor represented by this {@code Constructor} object. |
| */ |
| public Class<T> getDeclaringClass() { |
| return clazz; |
| } |
| |
| /** |
| * Returns the name of this constructor, as a string. This is |
| * the binary name of the constructor's declaring class. |
| */ |
| public String getName() { |
| return getDeclaringClass().getName(); |
| } |
| |
| /** |
| * Returns the Java language modifiers for the constructor |
| * represented by this {@code Constructor} object, as an integer. The |
| * {@code Modifier} class should be used to decode the modifiers. |
| * |
| * @see Modifier |
| */ |
| public int getModifiers() { |
| return modifiers; |
| } |
| |
| /** |
| * Returns an array of {@code TypeVariable} objects that represent the |
| * type variables declared by the generic declaration represented by this |
| * {@code GenericDeclaration} object, in declaration order. Returns an |
| * array of length 0 if the underlying generic declaration declares no type |
| * variables. |
| * |
| * @return an array of {@code TypeVariable} objects that represent |
| * the type variables declared by this generic declaration |
| * @throws GenericSignatureFormatError if the generic |
| * signature of this generic declaration does not conform to |
| * the format specified in |
| * <cite>The Java™ Virtual Machine Specification</cite> |
| * @since 1.5 |
| */ |
| public TypeVariable<Constructor<T>>[] getTypeParameters() { |
| if (getSignature() != null) { |
| return (TypeVariable<Constructor<T>>[])getGenericInfo().getTypeParameters(); |
| } else |
| return (TypeVariable<Constructor<T>>[])new TypeVariable[0]; |
| } |
| |
| |
| /** |
| * Returns an array of {@code Class} objects that represent the formal |
| * parameter types, in declaration order, of the constructor |
| * represented by this {@code Constructor} object. Returns an array of |
| * length 0 if the underlying constructor takes no parameters. |
| * |
| * @return the parameter types for the constructor this object |
| * represents |
| */ |
| public Class<?>[] getParameterTypes() { |
| return (Class<?>[]) parameterTypes.clone(); |
| } |
| |
| |
| /** |
| * Returns an array of {@code Type} objects that represent the formal |
| * parameter types, in declaration order, of the method represented by |
| * this {@code Constructor} object. Returns an array of length 0 if the |
| * underlying method takes no parameters. |
| * |
| * <p>If a formal parameter type is a parameterized type, |
| * the {@code Type} object returned for it must accurately reflect |
| * the actual type parameters used in the source code. |
| * |
| * <p>If a formal parameter type is a type variable or a parameterized |
| * type, it is created. Otherwise, it is resolved. |
| * |
| * @return an array of {@code Type}s that represent the formal |
| * parameter types of the underlying method, in declaration order |
| * @throws GenericSignatureFormatError |
| * if the generic method signature does not conform to the format |
| * specified in |
| * <cite>The Java™ Virtual Machine Specification</cite> |
| * @throws TypeNotPresentException if any of the parameter |
| * types of the underlying method refers to a non-existent type |
| * declaration |
| * @throws MalformedParameterizedTypeException if any of |
| * the underlying method's parameter types refer to a parameterized |
| * type that cannot be instantiated for any reason |
| * @since 1.5 |
| */ |
| public Type[] getGenericParameterTypes() { |
| if (getSignature() != null) |
| return getGenericInfo().getParameterTypes(); |
| else |
| return getParameterTypes(); |
| } |
| |
| |
| /** |
| * Returns an array of {@code Class} objects that represent the types |
| * of exceptions declared to be thrown by the underlying constructor |
| * represented by this {@code Constructor} object. Returns an array of |
| * length 0 if the constructor declares no exceptions in its {@code throws} clause. |
| * |
| * @return the exception types declared as being thrown by the |
| * constructor this object represents |
| */ |
| public Class<?>[] getExceptionTypes() { |
| return (Class<?>[])exceptionTypes.clone(); |
| } |
| |
| |
| /** |
| * Returns an array of {@code Type} objects that represent the |
| * exceptions declared to be thrown by this {@code Constructor} object. |
| * Returns an array of length 0 if the underlying method declares |
| * no exceptions in its {@code throws} clause. |
| * |
| * <p>If an exception type is a type variable or a parameterized |
| * type, it is created. Otherwise, it is resolved. |
| * |
| * @return an array of Types that represent the exception types |
| * thrown by the underlying method |
| * @throws GenericSignatureFormatError |
| * if the generic method signature does not conform to the format |
| * specified in |
| * <cite>The Java™ Virtual Machine Specification</cite> |
| * @throws TypeNotPresentException if the underlying method's |
| * {@code throws} clause refers to a non-existent type declaration |
| * @throws MalformedParameterizedTypeException if |
| * the underlying method's {@code throws} clause refers to a |
| * parameterized type that cannot be instantiated for any reason |
| * @since 1.5 |
| */ |
| public Type[] getGenericExceptionTypes() { |
| Type[] result; |
| if (getSignature() != null && |
| ( (result = getGenericInfo().getExceptionTypes()).length > 0 )) |
| return result; |
| else |
| return getExceptionTypes(); |
| } |
| |
| /** |
| * Compares this {@code Constructor} against the specified object. |
| * Returns true if the objects are the same. Two {@code Constructor} objects are |
| * the same if they were declared by the same class and have the |
| * same formal parameter types. |
| */ |
| public boolean equals(Object obj) { |
| if (obj != null && obj instanceof Constructor) { |
| Constructor<?> other = (Constructor<?>)obj; |
| if (getDeclaringClass() == other.getDeclaringClass()) { |
| /* Avoid unnecessary cloning */ |
| Class<?>[] params1 = parameterTypes; |
| Class<?>[] params2 = other.parameterTypes; |
| if (params1.length == params2.length) { |
| for (int i = 0; i < params1.length; i++) { |
| if (params1[i] != params2[i]) |
| return false; |
| } |
| return true; |
| } |
| } |
| } |
| return false; |
| } |
| |
| /** |
| * Returns a hashcode for this {@code Constructor}. The hashcode is |
| * the same as the hashcode for the underlying constructor's |
| * declaring class name. |
| */ |
| public int hashCode() { |
| return getDeclaringClass().getName().hashCode(); |
| } |
| |
| /** |
| * Returns a string describing this {@code Constructor}. The string is |
| * formatted as the constructor access modifiers, if any, |
| * followed by the fully-qualified name of the declaring class, |
| * followed by a parenthesized, comma-separated list of the |
| * constructor's formal parameter types. For example: |
| * <pre> |
| * public java.util.Hashtable(int,float) |
| * </pre> |
| * |
| * <p>The only possible modifiers for constructors are the access |
| * modifiers {@code public}, {@code protected} or |
| * {@code private}. Only one of these may appear, or none if the |
| * constructor has default (package) access. |
| */ |
| public String toString() { |
| try { |
| StringBuffer sb = new StringBuffer(); |
| int mod = getModifiers() & Modifier.constructorModifiers(); |
| if (mod != 0) { |
| sb.append(Modifier.toString(mod) + " "); |
| } |
| sb.append(Field.getTypeName(getDeclaringClass())); |
| sb.append("("); |
| Class<?>[] params = parameterTypes; // avoid clone |
| for (int j = 0; j < params.length; j++) { |
| sb.append(Field.getTypeName(params[j])); |
| if (j < (params.length - 1)) |
| sb.append(","); |
| } |
| sb.append(")"); |
| Class<?>[] exceptions = exceptionTypes; // avoid clone |
| if (exceptions.length > 0) { |
| sb.append(" throws "); |
| for (int k = 0; k < exceptions.length; k++) { |
| sb.append(exceptions[k].getName()); |
| if (k < (exceptions.length - 1)) |
| sb.append(","); |
| } |
| } |
| return sb.toString(); |
| } catch (Exception e) { |
| return "<" + e + ">"; |
| } |
| } |
| |
| /** |
| * Returns a string describing this {@code Constructor}, |
| * including type parameters. The string is formatted as the |
| * constructor access modifiers, if any, followed by an |
| * angle-bracketed comma separated list of the constructor's type |
| * parameters, if any, followed by the fully-qualified name of the |
| * declaring class, followed by a parenthesized, comma-separated |
| * list of the constructor's generic formal parameter types. |
| * |
| * If this constructor was declared to take a variable number of |
| * arguments, instead of denoting the last parameter as |
| * "<tt><i>Type</i>[]</tt>", it is denoted as |
| * "<tt><i>Type</i>...</tt>". |
| * |
| * A space is used to separate access modifiers from one another |
| * and from the type parameters or return type. If there are no |
| * type parameters, the type parameter list is elided; if the type |
| * parameter list is present, a space separates the list from the |
| * class name. If the constructor is declared to throw |
| * exceptions, the parameter list is followed by a space, followed |
| * by the word "{@code throws}" followed by a |
| * comma-separated list of the thrown exception types. |
| * |
| * <p>The only possible modifiers for constructors are the access |
| * modifiers {@code public}, {@code protected} or |
| * {@code private}. Only one of these may appear, or none if the |
| * constructor has default (package) access. |
| * |
| * @return a string describing this {@code Constructor}, |
| * include type parameters |
| * |
| * @since 1.5 |
| */ |
| public String toGenericString() { |
| try { |
| StringBuilder sb = new StringBuilder(); |
| int mod = getModifiers() & Modifier.constructorModifiers(); |
| if (mod != 0) { |
| sb.append(Modifier.toString(mod) + " "); |
| } |
| TypeVariable<?>[] typeparms = getTypeParameters(); |
| if (typeparms.length > 0) { |
| boolean first = true; |
| sb.append("<"); |
| for(TypeVariable<?> typeparm: typeparms) { |
| if (!first) |
| sb.append(","); |
| // Class objects can't occur here; no need to test |
| // and call Class.getName(). |
| sb.append(typeparm.toString()); |
| first = false; |
| } |
| sb.append("> "); |
| } |
| sb.append(Field.getTypeName(getDeclaringClass())); |
| sb.append("("); |
| Type[] params = getGenericParameterTypes(); |
| for (int j = 0; j < params.length; j++) { |
| String param = (params[j] instanceof Class<?>)? |
| Field.getTypeName((Class<?>)params[j]): |
| (params[j].toString()); |
| if (isVarArgs() && (j == params.length - 1)) // replace T[] with T... |
| param = param.replaceFirst("\\[\\]$", "..."); |
| sb.append(param); |
| if (j < (params.length - 1)) |
| sb.append(","); |
| } |
| sb.append(")"); |
| Type[] exceptions = getGenericExceptionTypes(); |
| if (exceptions.length > 0) { |
| sb.append(" throws "); |
| for (int k = 0; k < exceptions.length; k++) { |
| sb.append((exceptions[k] instanceof Class)? |
| ((Class<?>)exceptions[k]).getName(): |
| exceptions[k].toString()); |
| if (k < (exceptions.length - 1)) |
| sb.append(","); |
| } |
| } |
| return sb.toString(); |
| } catch (Exception e) { |
| return "<" + e + ">"; |
| } |
| } |
| |
| /** |
| * Uses the constructor represented by this {@code Constructor} object to |
| * create and initialize a new instance of the constructor's |
| * declaring class, with the specified initialization parameters. |
| * Individual parameters are automatically unwrapped to match |
| * primitive formal parameters, and both primitive and reference |
| * parameters are subject to method invocation conversions as necessary. |
| * |
| * <p>If the number of formal parameters required by the underlying constructor |
| * is 0, the supplied {@code initargs} array may be of length 0 or null. |
| * |
| * <p>If the constructor's declaring class is an inner class in a |
| * non-static context, the first argument to the constructor needs |
| * to be the enclosing instance; see section 15.9.3 of |
| * <cite>The Java™ Language Specification</cite>. |
| * |
| * <p>If the required access and argument checks succeed and the |
| * instantiation will proceed, the constructor's declaring class |
| * is initialized if it has not already been initialized. |
| * |
| * <p>If the constructor completes normally, returns the newly |
| * created and initialized instance. |
| * |
| * @param initargs array of objects to be passed as arguments to |
| * the constructor call; values of primitive types are wrapped in |
| * a wrapper object of the appropriate type (e.g. a {@code float} |
| * in a {@link java.lang.Float Float}) |
| * |
| * @return a new object created by calling the constructor |
| * this object represents |
| * |
| * @exception IllegalAccessException if this {@code Constructor} object |
| * is enforcing Java language access control and the underlying |
| * constructor is inaccessible. |
| * @exception IllegalArgumentException if the number of actual |
| * and formal parameters differ; if an unwrapping |
| * conversion for primitive arguments fails; or if, |
| * after possible unwrapping, a parameter value |
| * cannot be converted to the corresponding formal |
| * parameter type by a method invocation conversion; if |
| * this constructor pertains to an enum type. |
| * @exception InstantiationException if the class that declares the |
| * underlying constructor represents an abstract class. |
| * @exception InvocationTargetException if the underlying constructor |
| * throws an exception. |
| * @exception ExceptionInInitializerError if the initialization provoked |
| * by this method fails. |
| */ |
| @CallerSensitive |
| public T newInstance(Object ... initargs) |
| throws InstantiationException, IllegalAccessException, |
| IllegalArgumentException, InvocationTargetException |
| { |
| if (!override) { |
| if (!Reflection.quickCheckMemberAccess(clazz, modifiers)) { |
| Class<?> caller = Reflection.getCallerClass(); |
| checkAccess(caller, clazz, null, modifiers); |
| } |
| } |
| if ((clazz.getModifiers() & Modifier.ENUM) != 0) |
| throw new IllegalArgumentException("Cannot reflectively create enum objects"); |
| ConstructorAccessor ca = constructorAccessor; // read volatile |
| if (ca == null) { |
| ca = acquireConstructorAccessor(); |
| } |
| return (T) ca.newInstance(initargs); |
| } |
| |
| /** |
| * Returns {@code true} if this constructor was declared to take |
| * a variable number of arguments; returns {@code false} |
| * otherwise. |
| * |
| * @return {@code true} if an only if this constructor was declared to |
| * take a variable number of arguments. |
| * @since 1.5 |
| */ |
| public boolean isVarArgs() { |
| return (getModifiers() & Modifier.VARARGS) != 0; |
| } |
| |
| /** |
| * Returns {@code true} if this constructor is a synthetic |
| * constructor; returns {@code false} otherwise. |
| * |
| * @return true if and only if this constructor is a synthetic |
| * constructor as defined by |
| * <cite>The Java™ Language Specification</cite>. |
| * @since 1.5 |
| */ |
| public boolean isSynthetic() { |
| return Modifier.isSynthetic(getModifiers()); |
| } |
| |
| // NOTE that there is no synchronization used here. It is correct |
| // (though not efficient) to generate more than one |
| // ConstructorAccessor for a given Constructor. However, avoiding |
| // synchronization will probably make the implementation more |
| // scalable. |
| private ConstructorAccessor acquireConstructorAccessor() { |
| // First check to see if one has been created yet, and take it |
| // if so. |
| ConstructorAccessor tmp = null; |
| if (root != null) tmp = root.getConstructorAccessor(); |
| if (tmp != null) { |
| constructorAccessor = tmp; |
| } else { |
| // Otherwise fabricate one and propagate it up to the root |
| tmp = reflectionFactory.newConstructorAccessor(this); |
| setConstructorAccessor(tmp); |
| } |
| |
| return tmp; |
| } |
| |
| // Returns ConstructorAccessor for this Constructor object, not |
| // looking up the chain to the root |
| ConstructorAccessor getConstructorAccessor() { |
| return constructorAccessor; |
| } |
| |
| // Sets the ConstructorAccessor for this Constructor object and |
| // (recursively) its root |
| void setConstructorAccessor(ConstructorAccessor accessor) { |
| constructorAccessor = accessor; |
| // Propagate up |
| if (root != null) { |
| root.setConstructorAccessor(accessor); |
| } |
| } |
| |
| int getSlot() { |
| return slot; |
| } |
| |
| String getSignature() { |
| return signature; |
| } |
| |
| byte[] getRawAnnotations() { |
| return annotations; |
| } |
| |
| byte[] getRawParameterAnnotations() { |
| return parameterAnnotations; |
| } |
| |
| /** |
| * @throws NullPointerException {@inheritDoc} |
| * @since 1.5 |
| */ |
| public <T extends Annotation> T getAnnotation(Class<T> annotationClass) { |
| if (annotationClass == null) |
| throw new NullPointerException(); |
| |
| return (T) declaredAnnotations().get(annotationClass); |
| } |
| |
| /** |
| * @since 1.5 |
| */ |
| public Annotation[] getDeclaredAnnotations() { |
| return AnnotationParser.toArray(declaredAnnotations()); |
| } |
| |
| private transient Map<Class<? extends Annotation>, Annotation> declaredAnnotations; |
| |
| private synchronized Map<Class<? extends Annotation>, Annotation> declaredAnnotations() { |
| if (declaredAnnotations == null) { |
| declaredAnnotations = AnnotationParser.parseAnnotations( |
| annotations, sun.misc.SharedSecrets.getJavaLangAccess(). |
| getConstantPool(getDeclaringClass()), |
| getDeclaringClass()); |
| } |
| return declaredAnnotations; |
| } |
| |
| /** |
| * Returns an array of arrays that represent the annotations on the formal |
| * parameters, in declaration order, of the method represented by |
| * this {@code Constructor} object. (Returns an array of length zero if the |
| * underlying method is parameterless. If the method has one or more |
| * parameters, a nested array of length zero is returned for each parameter |
| * with no annotations.) The annotation objects contained in the returned |
| * arrays are serializable. The caller of this method is free to modify |
| * the returned arrays; it will have no effect on the arrays returned to |
| * other callers. |
| * |
| * @return an array of arrays that represent the annotations on the formal |
| * parameters, in declaration order, of the method represented by this |
| * Constructor object |
| * @since 1.5 |
| */ |
| public Annotation[][] getParameterAnnotations() { |
| int numParameters = parameterTypes.length; |
| if (parameterAnnotations == null) |
| return new Annotation[numParameters][0]; |
| |
| Annotation[][] result = AnnotationParser.parseParameterAnnotations( |
| parameterAnnotations, |
| sun.misc.SharedSecrets.getJavaLangAccess(). |
| getConstantPool(getDeclaringClass()), |
| getDeclaringClass()); |
| if (result.length != numParameters) { |
| Class<?> declaringClass = getDeclaringClass(); |
| if (declaringClass.isEnum() || |
| declaringClass.isAnonymousClass() || |
| declaringClass.isLocalClass() ) |
| ; // Can't do reliable parameter counting |
| else { |
| if (!declaringClass.isMemberClass() || // top-level |
| // Check for the enclosing instance parameter for |
| // non-static member classes |
| (declaringClass.isMemberClass() && |
| ((declaringClass.getModifiers() & Modifier.STATIC) == 0) && |
| result.length + 1 != numParameters) ) { |
| throw new AnnotationFormatError( |
| "Parameter annotations don't match number of parameters"); |
| } |
| } |
| } |
| return result; |
| } |
| } |
