sun.reflect.annotation.AnnotationInvocationHandler Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of a-javabeans8 Show documentation
Show all versions of a-javabeans8 Show documentation
Adapted (moved from java.beans to ajava.beans) OpenJDK8 javabeans for Android. It's used by A-Jetty (Jetty 9.2 adapted for Android.)
The newest version!
/*
* Copyright (c) 2003, 2014, 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 sun.reflect.annotation;
import java.io.ObjectInputStream;
import java.lang.annotation.*;
import java.lang.reflect.*;
import java.io.Serializable;
import java.util.*;
import java.security.AccessController;
import java.security.PrivilegedAction;
/**
* InvocationHandler for dynamic proxy implementation of Annotation.
*
* @author Josh Bloch
* @since 1.5
*/
class AnnotationInvocationHandler implements InvocationHandler, Serializable {
private static final long serialVersionUID = 6182022883658399397L;
private final Class type;
private final Map memberValues;
AnnotationInvocationHandler(Class type, Map memberValues) {
Class[] superInterfaces = type.getInterfaces();
if (!type.isAnnotation() ||
superInterfaces.length != 1 ||
superInterfaces[0] != java.lang.annotation.Annotation.class)
throw new AnnotationFormatError("Attempt to create proxy for a non-annotation type.");
this.type = type;
this.memberValues = memberValues;
}
public Object invoke(Object proxy, Method method, Object[] args) {
String member = method.getName();
Class[] paramTypes = method.getParameterTypes();
// Handle Object and Annotation methods
if (member.equals("equals") && paramTypes.length == 1 &&
paramTypes[0] == Object.class)
return equalsImpl(args[0]);
if (paramTypes.length != 0)
throw new AssertionError("Too many parameters for an annotation method");
switch(member) {
case "toString":
return toStringImpl();
case "hashCode":
return hashCodeImpl();
case "annotationType":
return type;
}
// Handle annotation member accessors
Object result = memberValues.get(member);
if (result == null)
throw new IncompleteAnnotationException(type, member);
if (result instanceof ExceptionProxy)
throw ((ExceptionProxy) result).generateException();
if (result.getClass().isArray() && Array.getLength(result) != 0)
result = cloneArray(result);
return result;
}
/**
* This method, which clones its array argument, would not be necessary
* if Cloneable had a public clone method.
*/
private Object cloneArray(Object array) {
Class type = array.getClass();
if (type == byte[].class) {
byte[] byteArray = (byte[])array;
return byteArray.clone();
}
if (type == char[].class) {
char[] charArray = (char[])array;
return charArray.clone();
}
if (type == double[].class) {
double[] doubleArray = (double[])array;
return doubleArray.clone();
}
if (type == float[].class) {
float[] floatArray = (float[])array;
return floatArray.clone();
}
if (type == int[].class) {
int[] intArray = (int[])array;
return intArray.clone();
}
if (type == long[].class) {
long[] longArray = (long[])array;
return longArray.clone();
}
if (type == short[].class) {
short[] shortArray = (short[])array;
return shortArray.clone();
}
if (type == boolean[].class) {
boolean[] booleanArray = (boolean[])array;
return booleanArray.clone();
}
Object[] objectArray = (Object[])array;
return objectArray.clone();
}
/**
* Implementation of dynamicProxy.toString()
*/
private String toStringImpl() {
StringBuilder result = new StringBuilder(128);
result.append('@');
result.append(type.getName());
result.append('(');
boolean firstMember = true;
for (Map.Entry e : memberValues.entrySet()) {
if (firstMember)
firstMember = false;
else
result.append(", ");
result.append(e.getKey());
result.append('=');
result.append(memberValueToString(e.getValue()));
}
result.append(')');
return result.toString();
}
/**
* Translates a member value (in "dynamic proxy return form") into a string
*/
private static String memberValueToString(Object value) {
Class type = value.getClass();
if (!type.isArray()) // primitive, string, class, enum const,
// or annotation
return value.toString();
if (type == byte[].class)
return Arrays.toString((byte[]) value);
if (type == char[].class)
return Arrays.toString((char[]) value);
if (type == double[].class)
return Arrays.toString((double[]) value);
if (type == float[].class)
return Arrays.toString((float[]) value);
if (type == int[].class)
return Arrays.toString((int[]) value);
if (type == long[].class)
return Arrays.toString((long[]) value);
if (type == short[].class)
return Arrays.toString((short[]) value);
if (type == boolean[].class)
return Arrays.toString((boolean[]) value);
return Arrays.toString((Object[]) value);
}
/**
* Implementation of dynamicProxy.equals(Object o)
*/
private Boolean equalsImpl(Object o) {
if (o == this)
return true;
if (!type.isInstance(o))
return false;
for (Method memberMethod : getMemberMethods()) {
String member = memberMethod.getName();
Object ourValue = memberValues.get(member);
Object hisValue = null;
AnnotationInvocationHandler hisHandler = asOneOfUs(o);
if (hisHandler != null) {
hisValue = hisHandler.memberValues.get(member);
} else {
try {
hisValue = memberMethod.invoke(o);
} catch (InvocationTargetException e) {
return false;
} catch (IllegalAccessException e) {
throw new AssertionError(e);
}
}
if (!memberValueEquals(ourValue, hisValue))
return false;
}
return true;
}
/**
* Returns an object's invocation handler if that object is a dynamic
* proxy with a handler of type AnnotationInvocationHandler.
* Returns null otherwise.
*/
private AnnotationInvocationHandler asOneOfUs(Object o) {
if (Proxy.isProxyClass(o.getClass())) {
InvocationHandler handler = Proxy.getInvocationHandler(o);
if (handler instanceof AnnotationInvocationHandler)
return (AnnotationInvocationHandler) handler;
}
return null;
}
/**
* Returns true iff the two member values in "dynamic proxy return form"
* are equal using the appropriate equality function depending on the
* member type. The two values will be of the same type unless one of
* the containing annotations is ill-formed. If one of the containing
* annotations is ill-formed, this method will return false unless the
* two members are identical object references.
*/
private static boolean memberValueEquals(Object v1, Object v2) {
Class type = v1.getClass();
// Check for primitive, string, class, enum const, annotation,
// or ExceptionProxy
if (!type.isArray())
return v1.equals(v2);
// Check for array of string, class, enum const, annotation,
// or ExceptionProxy
if (v1 instanceof Object[] && v2 instanceof Object[])
return Arrays.equals((Object[]) v1, (Object[]) v2);
// Check for ill formed annotation(s)
if (v2.getClass() != type)
return false;
// Deal with array of primitives
if (type == byte[].class)
return Arrays.equals((byte[]) v1, (byte[]) v2);
if (type == char[].class)
return Arrays.equals((char[]) v1, (char[]) v2);
if (type == double[].class)
return Arrays.equals((double[]) v1, (double[]) v2);
if (type == float[].class)
return Arrays.equals((float[]) v1, (float[]) v2);
if (type == int[].class)
return Arrays.equals((int[]) v1, (int[]) v2);
if (type == long[].class)
return Arrays.equals((long[]) v1, (long[]) v2);
if (type == short[].class)
return Arrays.equals((short[]) v1, (short[]) v2);
assert type == boolean[].class;
return Arrays.equals((boolean[]) v1, (boolean[]) v2);
}
/**
* Returns the member methods for our annotation type. These are
* obtained lazily and cached, as they're expensive to obtain
* and we only need them if our equals method is invoked (which should
* be rare).
*/
private Method[] getMemberMethods() {
if (memberMethods == null) {
memberMethods = AccessController.doPrivileged(
new PrivilegedAction() {
public Method[] run() {
final Method[] mm = type.getDeclaredMethods();
validateAnnotationMethods(mm);
AccessibleObject.setAccessible(mm, true);
return mm;
}
});
}
return memberMethods;
}
private transient volatile Method[] memberMethods = null;
/**
* Validates that a method is structurally appropriate for an
* annotation type. As of Java SE 8, annotation types cannot
* contain static methods and the declared methods of an
* annotation type must take zero arguments and there are
* restrictions on the return type.
*/
private void validateAnnotationMethods(Method[] memberMethods) {
/*
* Specification citations below are from JLS
* 9.6.1. Annotation Type Elements
*/
boolean valid = true;
for(Method method : memberMethods) {
/*
* "By virtue of the AnnotationTypeElementDeclaration
* production, a method declaration in an annotation type
* declaration cannot have formal parameters, type
* parameters, or a throws clause.
*
* "By virtue of the AnnotationTypeElementModifier
* production, a method declaration in an annotation type
* declaration cannot be default or static."
*/
if (method.getModifiers() != (Modifier.PUBLIC | Modifier.ABSTRACT) ||
method.isDefault() ||
method.getParameterCount() != 0 ||
method.getExceptionTypes().length != 0) {
valid = false;
break;
}
/*
* "It is a compile-time error if the return type of a
* method declared in an annotation type is not one of the
* following: a primitive type, String, Class, any
* parameterized invocation of Class, an enum type
* (section 8.9), an annotation type, or an array type
* (chapter 10) whose element type is one of the preceding
* types."
*/
Class returnType = method.getReturnType();
if (returnType.isArray()) {
returnType = returnType.getComponentType();
if (returnType.isArray()) { // Only single dimensional arrays
valid = false;
break;
}
}
if (!((returnType.isPrimitive() && returnType != void.class) ||
returnType == java.lang.String.class ||
returnType == java.lang.Class.class ||
returnType.isEnum() ||
returnType.isAnnotation())) {
valid = false;
break;
}
/*
* "It is a compile-time error if any method declared in an
* annotation type has a signature that is
* override-equivalent to that of any public or protected
* method declared in class Object or in the interface
* java.lang.annotation.Annotation."
*
* The methods in Object or Annotation meeting the other
* criteria (no arguments, contrained return type, etc.)
* above are:
*
* String toString()
* int hashCode()
* Class annotationType()
*/
String methodName = method.getName();
if ((methodName.equals("toString") && returnType == java.lang.String.class) ||
(methodName.equals("hashCode") && returnType == int.class) ||
(methodName.equals("annotationType") && returnType == java.lang.Class.class)) {
valid = false;
break;
}
}
if (valid)
return;
else
throw new AnnotationFormatError("Malformed method on an annotation type");
}
/**
* Implementation of dynamicProxy.hashCode()
*/
private int hashCodeImpl() {
int result = 0;
for (Map.Entry e : memberValues.entrySet()) {
result += (127 * e.getKey().hashCode()) ^
memberValueHashCode(e.getValue());
}
return result;
}
/**
* Computes hashCode of a member value (in "dynamic proxy return form")
*/
private static int memberValueHashCode(Object value) {
Class type = value.getClass();
if (!type.isArray()) // primitive, string, class, enum const,
// or annotation
return value.hashCode();
if (type == byte[].class)
return Arrays.hashCode((byte[]) value);
if (type == char[].class)
return Arrays.hashCode((char[]) value);
if (type == double[].class)
return Arrays.hashCode((double[]) value);
if (type == float[].class)
return Arrays.hashCode((float[]) value);
if (type == int[].class)
return Arrays.hashCode((int[]) value);
if (type == long[].class)
return Arrays.hashCode((long[]) value);
if (type == short[].class)
return Arrays.hashCode((short[]) value);
if (type == boolean[].class)
return Arrays.hashCode((boolean[]) value);
return Arrays.hashCode((Object[]) value);
}
private void readObject(java.io.ObjectInputStream s)
throws java.io.IOException, ClassNotFoundException {
ObjectInputStream.GetField fields = s.readFields();
@SuppressWarnings("unchecked")
Class t = (Class)fields.get("type", null);
@SuppressWarnings("unchecked")
Map streamVals = (Map)fields.get("memberValues", null);
// Check to make sure that types have not evolved incompatibly
AnnotationType annotationType = null;
try {
annotationType = AnnotationType.getInstance(t);
} catch(IllegalArgumentException e) {
// Class is no longer an annotation type; time to punch out
throw new java.io.InvalidObjectException("Non-annotation type in annotation serial stream");
}
Map> memberTypes = annotationType.memberTypes();
// consistent with runtime Map type
Map mv = new LinkedHashMap<>();
// If there are annotation members without values, that
// situation is handled by the invoke method.
for (Map.Entry memberValue : streamVals.entrySet()) {
String name = memberValue.getKey();
Object value = null;
Class memberType = memberTypes.get(name);
if (memberType != null) { // i.e. member still exists
value = memberValue.getValue();
if (!(memberType.isInstance(value) ||
value instanceof ExceptionProxy)) {
value = new AnnotationTypeMismatchExceptionProxy(
value.getClass() + "[" + value + "]").setMember(
annotationType.members().get(name));
}
}
mv.put(name, value);
}
UnsafeAccessor.setType(this, t);
UnsafeAccessor.setMemberValues(this, mv);
}
private static class UnsafeAccessor {
private static final sun.misc.Unsafe unsafe;
private static final long typeOffset;
private static final long memberValuesOffset;
static {
try {
unsafe = sun.misc.Unsafe.getUnsafe();
typeOffset = unsafe.objectFieldOffset
(AnnotationInvocationHandler.class.getDeclaredField("type"));
memberValuesOffset = unsafe.objectFieldOffset
(AnnotationInvocationHandler.class.getDeclaredField("memberValues"));
} catch (Exception ex) {
throw new ExceptionInInitializerError(ex);
}
}
static void setType(AnnotationInvocationHandler o,
Class type) {
unsafe.putObject(o, typeOffset, type);
}
static void setMemberValues(AnnotationInvocationHandler o,
Map memberValues) {
unsafe.putObject(o, memberValuesOffset, memberValues);
}
}
}