All Downloads are FREE. Search and download functionalities are using the official Maven repository.

com.sun.xml.bind.v2.model.nav.ReflectionNavigator Maven / Gradle / Ivy

There is a newer version: 4.0.5
Show newest version
/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 *
 * Copyright (c) 1997-2010 Oracle and/or its affiliates. All rights reserved.
 *
 * The contents of this file are subject to the terms of either the GNU
 * General Public License Version 2 only ("GPL") or the Common Development
 * and Distribution License("CDDL") (collectively, the "License").  You
 * may not use this file except in compliance with the License.  You can
 * obtain a copy of the License at
 * https://glassfish.dev.java.net/public/CDDL+GPL_1_1.html
 * or packager/legal/LICENSE.txt.  See the License for the specific
 * language governing permissions and limitations under the License.
 *
 * When distributing the software, include this License Header Notice in each
 * file and include the License file at packager/legal/LICENSE.txt.
 *
 * GPL Classpath Exception:
 * Oracle designates this particular file as subject to the "Classpath"
 * exception as provided by Oracle in the GPL Version 2 section of the License
 * file that accompanied this code.
 *
 * Modifications:
 * If applicable, add the following below the License Header, with the fields
 * enclosed by brackets [] replaced by your own identifying information:
 * "Portions Copyright [year] [name of copyright owner]"
 *
 * Contributor(s):
 * If you wish your version of this file to be governed by only the CDDL or
 * only the GPL Version 2, indicate your decision by adding "[Contributor]
 * elects to include this software in this distribution under the [CDDL or GPL
 * Version 2] license."  If you don't indicate a single choice of license, a
 * recipient has the option to distribute your version of this file under
 * either the CDDL, the GPL Version 2 or to extend the choice of license to
 * its licensees as provided above.  However, if you add GPL Version 2 code
 * and therefore, elected the GPL Version 2 license, then the option applies
 * only if the new code is made subject to such option by the copyright
 * holder.
 */

package com.sun.xml.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.bind.v2.runtime.Location;

/**
 * {@link Navigator} implementation for {@code java.lang.reflect}.
 *
 */
public final class ReflectionNavigator implements Navigator {

    /**
     * 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 baseClassFinder = new TypeVisitor() {

        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 binder = new TypeVisitor() {

        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 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 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) {
        if (field.getType().isArray()) {
            Class c = field.getType().getComponentType();
            if (c.isPrimitive()) {
                return Array.newInstance(c, 0).getClass();
            }
        }
        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 isFinalMethod(Method method) {
        return Modifier.isFinal(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 eraser = new TypeVisitor() {

        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.
     *
     * 

* Because of the difference in the way Annotation Processing and the Java reflection * treats primitive type and array type, we can't define this method * on {@link Navigator}. * *

* 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 Class 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() { @Override public String toString() { return clazz.getName(); } }; } public Location getFieldLocation(final Field field) { return new Location() { @Override public String toString() { return field.toString(); } }; } public Location getMethodLocation(final Method method) { return new Location() { @Override 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 = SecureLoader.getClassClassLoader(referencePoint); if (cl == null) { cl = SecureLoader.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 getX() { ... } // } // class Base { // 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()); } @Override public boolean isSameType(Type t1, Type t2) { return t1.equals(t2); } /** * JDK 5.0 has a bug of creating {@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; } }





© 2015 - 2024 Weber Informatics LLC | Privacy Policy