/*
* Copyright (c) 2005, 2006, 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
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package com.sun.xml.internal.bind.v2.model.nav;
import java.lang.reflect.Array;
import java.lang.reflect.Field;
import java.lang.reflect.GenericArrayType;
import java.lang.reflect.GenericDeclaration;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.lang.reflect.TypeVariable;
import java.lang.reflect.WildcardType;
import java.util.Arrays;
import java.util.Collection;
import com.sun.xml.internal.bind.v2.runtime.Location;
/**
* {@link Navigator} implementation for {@code java.lang.reflect}.
*
*/
public final class ReflectionNavigator implements Navigator<Type,Class,Field,Method> {
/**
* Singleton.
*
* Use {@link Navigator#REFLECTION}
*/
ReflectionNavigator() {}
public Class getSuperClass(Class clazz) {
if(clazz==Object.class) return null;
Class sc = clazz.getSuperclass();
if(sc==null) sc=Object.class; // error recovery
return sc;
}
private static final TypeVisitor<Type,Class> baseClassFinder = new TypeVisitor<Type,Class>() {
public Type onClass(Class c, Class sup) {
// t is a raw type
if(sup==c)
return sup;
Type r;
Type sc = c.getGenericSuperclass();
if(sc!=null) {
r = visit(sc,sup);
if(r!=null) return r;
}
for( Type i : c.getGenericInterfaces() ) {
r = visit(i,sup);
if(r!=null) return r;
}
return null;
}
public Type onParameterizdType(ParameterizedType p, Class sup) {
Class raw = (Class) p.getRawType();
if(raw==sup) {
// p is of the form sup<...>
return p;
} else {
// recursively visit super class/interfaces
Type r = raw.getGenericSuperclass();
if(r!=null)
r = visit(bind(r,raw,p),sup);
if(r!=null)
return r;
for( Type i : raw.getGenericInterfaces() ) {
r = visit(bind(i,raw,p),sup);
if(r!=null) return r;
}
return null;
}
}
public Type onGenericArray(GenericArrayType g, Class sup) {
// not clear what I should do here
return null;
}
public Type onVariable(TypeVariable v, Class sup) {
return visit(v.getBounds()[0],sup);
}
public Type onWildcard(WildcardType w, Class sup) {
// not clear what I should do here
return null;
}
/**
* Replaces the type variables in {@code t} by its actual arguments.
*
* @param decl
* provides a list of type variables. See {@link GenericDeclaration#getTypeParameters()}
* @param args
* actual arguments. See {@link ParameterizedType#getActualTypeArguments()}
*/
private Type bind( Type t, GenericDeclaration decl, ParameterizedType args ) {
return binder.visit(t,new BinderArg(decl,args.getActualTypeArguments()));
}
};
private static class BinderArg {
final TypeVariable[] params;
final Type[] args;
BinderArg(TypeVariable[] params, Type[] args) {
this.params = params;
this.args = args;
assert params.length==args.length;
}
public BinderArg( GenericDeclaration decl, Type[] args ) {
this(decl.getTypeParameters(),args);
}
Type replace( TypeVariable v ) {
for(int i=0; i<params.length; i++)
if(params[i].equals(v))
return args[i];
return v; // this is a free variable
}
}
private static final TypeVisitor<Type,BinderArg> binder = new TypeVisitor<Type,BinderArg>() {
public Type onClass(Class c, BinderArg args) {
return c;
}
public Type onParameterizdType(ParameterizedType p, BinderArg args) {
Type[] params = p.getActualTypeArguments();
boolean different = false;
for( int i=0; i<params.length; i++ ) {
Type t = params[i];
params[i] = visit(t,args);
different |= t!=params[i];
}
Type newOwner = p.getOwnerType();
if(newOwner!=null)
newOwner = visit(newOwner,args);
different |= p.getOwnerType()!=newOwner;
if(!different) return p;
return new ParameterizedTypeImpl( (Class<?>)p.getRawType(), params, newOwner );
}
public Type onGenericArray(GenericArrayType g, BinderArg types) {
Type c = visit(g.getGenericComponentType(),types);
if(c==g.getGenericComponentType()) return g;
return new GenericArrayTypeImpl(c);
}
public Type onVariable(TypeVariable v, BinderArg types) {
return types.replace(v);
}
public Type onWildcard(WildcardType w, BinderArg types) {
// TODO: this is probably still incorrect
// bind( "? extends T" ) with T= "? extends Foo" should be "? extends Foo",
// not "? extends (? extends Foo)"
Type[] lb = w.getLowerBounds();
Type[] ub = w.getUpperBounds();
boolean diff = false;
for( int i=0; i<lb.length; i++ ) {
Type t = lb[i];
lb[i] = visit(t,types);
diff |= (t!=lb[i]);
}
for( int i=0; i<ub.length; i++ ) {
Type t = ub[i];
ub[i] = visit(t,types);
diff |= (t!=ub[i]);
}
if(!diff) return w;
return new WildcardTypeImpl(lb,ub);
}
};
public Type getBaseClass(Type t, Class sup) {
return baseClassFinder.visit(t,sup);
}
public String getClassName(Class clazz) {
return clazz.getName();
}
public String getTypeName(Type type) {
if (type instanceof Class) {
Class c = (Class) type;
if(c.isArray())
return getTypeName(c.getComponentType())+"[]";
return c.getName();
}
return type.toString();
}
public String getClassShortName(Class clazz) {
return clazz.getSimpleName();
}
public Collection<? extends Field> getDeclaredFields(Class clazz) {
return Arrays.asList(clazz.getDeclaredFields());
}
public Field getDeclaredField(Class clazz, String fieldName) {
try {
return clazz.getDeclaredField(fieldName);
} catch (NoSuchFieldException e) {
return null;
}
}
public Collection<? extends Method> getDeclaredMethods(Class clazz) {
return Arrays.asList(clazz.getDeclaredMethods());
}
public Class getDeclaringClassForField(Field field) {
return field.getDeclaringClass();
}
public Class getDeclaringClassForMethod(Method method) {
return method.getDeclaringClass();
}
public Type getFieldType(Field field) {
return fix(field.getGenericType());
}
public String getFieldName(Field field) {
return field.getName();
}
public String getMethodName(Method method) {
return method.getName();
}
public Type getReturnType(Method method) {
return fix(method.getGenericReturnType());
}
public Type[] getMethodParameters(Method method) {
return method.getGenericParameterTypes();
}
public boolean isStaticMethod(Method method) {
return Modifier.isStatic(method.getModifiers());
}
public boolean isSubClassOf(Type sub, Type sup) {
return erasure(sup).isAssignableFrom(erasure(sub));
}
public Class ref(Class c) {
return c;
}
public Class use(Class c) {
return c;
}
public Class asDecl(Type t) {
return erasure(t);
}
public Class asDecl(Class c) {
return c;
}
/**
* Implements the logic for {@link #erasure(Type)}.
*/
private static final TypeVisitor<Class,Void> eraser = new TypeVisitor<Class,Void>() {
public Class onClass(Class c,Void _) {
return c;
}
public Class onParameterizdType(ParameterizedType p,Void _) {
// TODO: why getRawType returns Type? not Class?
return visit(p.getRawType(),null);
}
public Class onGenericArray(GenericArrayType g,Void _) {
return Array.newInstance(
visit(g.getGenericComponentType(),null),
0 ).getClass();
}
public Class onVariable(TypeVariable v,Void _) {
return visit(v.getBounds()[0],null);
}
public Class onWildcard(WildcardType w,Void _) {
return visit(w.getUpperBounds()[0],null);
}
};
/**
* Returns the runtime representation of the given type.
*
* This corresponds to the notion of the erasure in JSR-14.
*
* <p>
* Because of the difference in the way APT and the Java reflection
* treats primitive type and array type, we can't define this method
* on {@link Navigator}.
*
* <p>
* It made me realize how difficult it is to define the common navigation
* layer for two different underlying reflection library. The other way
* is to throw away the entire parameterization and go to the wrapper approach.
*/
public <T> Class<T> erasure(Type t) {
return eraser.visit(t,null);
}
public boolean isAbstract(Class clazz) {
return Modifier.isAbstract(clazz.getModifiers());
}
public boolean isFinal(Class clazz) {
return Modifier.isFinal(clazz.getModifiers());
}
/**
* Returns the {@link Type} object that represents {@code clazz<T1,T2,T3>}.
*/
public Type createParameterizedType( Class rawType, Type... arguments ) {
return new ParameterizedTypeImpl(rawType,arguments,null);
}
public boolean isArray(Type t) {
if (t instanceof Class) {
Class c = (Class) t;
return c.isArray();
}
if(t instanceof GenericArrayType)
return true;
return false;
}
public boolean isArrayButNotByteArray(Type t) {
if (t instanceof Class) {
Class c = (Class) t;
return c.isArray() && c!=byte[].class;
}
if(t instanceof GenericArrayType) {
t = ((GenericArrayType)t).getGenericComponentType();
return t!=Byte.TYPE;
}
return false;
}
public Type getComponentType(Type t) {
if (t instanceof Class) {
Class c = (Class) t;
return c.getComponentType();
}
if(t instanceof GenericArrayType)
return ((GenericArrayType)t).getGenericComponentType();
throw new IllegalArgumentException();
}
public Type getTypeArgument(Type type, int i) {
if (type instanceof ParameterizedType) {
ParameterizedType p = (ParameterizedType) type;
return fix(p.getActualTypeArguments()[i]);
} else
throw new IllegalArgumentException();
}
public boolean isParameterizedType(Type type) {
return type instanceof ParameterizedType;
}
public boolean isPrimitive(Type type) {
if (type instanceof Class) {
Class c = (Class) type;
return c.isPrimitive();
}
return false;
}
public Type getPrimitive(Class primitiveType) {
assert primitiveType.isPrimitive();
return primitiveType;
}
public Location getClassLocation(final Class clazz) {
return new Location() {
public String toString() {
return clazz.getName();
}
};
}
public Location getFieldLocation(final Field field) {
return new Location() {
public String toString() {
return field.toString();
}
};
}
public Location getMethodLocation(final Method method) {
return new Location() {
public String toString() {
return method.toString();
}
};
}
public boolean hasDefaultConstructor(Class c) {
try {
c.getDeclaredConstructor();
return true;
} catch (NoSuchMethodException e) {
return false;
}
}
public boolean isStaticField(Field field) {
return Modifier.isStatic(field.getModifiers());
}
public boolean isPublicMethod(Method method) {
return Modifier.isPublic(method.getModifiers());
}
public boolean isPublicField(Field field) {
return Modifier.isPublic(field.getModifiers());
}
public boolean isEnum(Class c) {
return Enum.class.isAssignableFrom(c);
}
public Field[] getEnumConstants(Class clazz) {
try {
Object[] values = clazz.getEnumConstants();
Field[] fields = new Field[values.length];
for( int i=0; i<values.length; i++ ) {
fields[i] = clazz.getField(((Enum)values[i]).name());
}
return fields;
} catch (NoSuchFieldException e) {
// impossible
throw new NoSuchFieldError(e.getMessage());
}
}
public Type getVoidType() {
return Void.class;
}
public String getPackageName(Class clazz) {
String name = clazz.getName();
int idx = name.lastIndexOf('.');
if(idx<0) return "";
else return name.substring(0,idx);
}
public Class findClass(String className, Class referencePoint) {
try {
ClassLoader cl = referencePoint.getClassLoader();
if(cl==null) cl = ClassLoader.getSystemClassLoader();
return cl.loadClass(className);
} catch (ClassNotFoundException e) {
return null;
}
}
public boolean isBridgeMethod(Method method) {
return method.isBridge();
}
public boolean isOverriding(Method method, Class base) {
// this isn't actually correct,
// as the JLS considers
// class Derived extends Base<Integer> {
// Integer getX() { ... }
// }
// class Base<T> {
// T getX() { ... }
// }
// to be overrided. Handling this correctly needs a careful implementation
String name = method.getName();
Class[] params = method.getParameterTypes();
while(base!=null) {
try {
if(base.getDeclaredMethod(name,params)!=null)
return true;
} catch (NoSuchMethodException e) {
// recursively go into the base class
}
base = base.getSuperclass();
}
return false;
}
public boolean isInterface(Class clazz) {
return clazz.isInterface();
}
public boolean isTransient(Field f) {
return Modifier.isTransient(f.getModifiers());
}
public boolean isInnerClass(Class clazz) {
return clazz.getEnclosingClass()!=null && !Modifier.isStatic(clazz.getModifiers());
}
/**
* JDK 5.0 has a bug of createing {@link GenericArrayType} where it shouldn't.
* fix that manually to work around the problem.
*
* See bug 6202725.
*/
private Type fix(Type t) {
if(!(t instanceof GenericArrayType))
return t;
GenericArrayType gat = (GenericArrayType) t;
if(gat.getGenericComponentType() instanceof Class) {
Class c = (Class) gat.getGenericComponentType();
return Array.newInstance(c,0).getClass();
}
return t;
}
}