/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package javax.el;
import java.beans.BeanInfo;
import java.beans.FeatureDescriptor;
import java.beans.IntrospectionException;
import java.beans.Introspector;
import java.beans.PropertyDescriptor;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.WeakHashMap;
import java.util.concurrent.ConcurrentHashMap;
public class BeanELResolver extends ELResolver {
private final boolean readOnly;
private final ConcurrentCache<String, BeanProperties> cache = new ConcurrentCache<String, BeanProperties>(
1000);
public BeanELResolver() {
this.readOnly = false;
}
public BeanELResolver(boolean readOnly) {
this.readOnly = readOnly;
}
public Object getValue(ELContext context, Object base, Object property)
throws NullPointerException, PropertyNotFoundException, ELException {
if (context == null) {
throw new NullPointerException();
}
if (base == null || property == null) {
return null;
}
context.setPropertyResolved(true);
Method m = this.property(context, base, property).read(context);
try {
return m.invoke(base, (Object[]) null);
} catch (IllegalAccessException e) {
throw new ELException(e);
} catch (InvocationTargetException e) {
throw new ELException(message(context, "propertyReadError",
new Object[] { base.getClass().getName(),
property.toString() }), e.getCause());
} catch (Exception e) {
throw new ELException(e);
}
}
public Class<?> getType(ELContext context, Object base, Object property)
throws NullPointerException, PropertyNotFoundException, ELException {
if (context == null) {
throw new NullPointerException();
}
if (base == null || property == null) {
return null;
}
context.setPropertyResolved(true);
return this.property(context, base, property).getPropertyType();
}
public void setValue(ELContext context, Object base, Object property,
Object value) throws NullPointerException,
PropertyNotFoundException, PropertyNotWritableException,
ELException {
if (context == null) {
throw new NullPointerException();
}
if (base == null || property == null) {
return;
}
context.setPropertyResolved(true);
if (this.readOnly) {
throw new PropertyNotWritableException(message(context,
"resolverNotWriteable", new Object[] { base.getClass()
.getName() }));
}
Method m = this.property(context, base, property).write(context);
try {
m.invoke(base, value);
} catch (IllegalAccessException e) {
throw new ELException(e);
} catch (InvocationTargetException e) {
throw new ELException(message(context, "propertyWriteError",
new Object[] { base.getClass().getName(),
property.toString() }), e.getCause());
} catch (Exception e) {
throw new ELException(e);
}
}
public boolean isReadOnly(ELContext context, Object base, Object property)
throws NullPointerException, PropertyNotFoundException, ELException {
if (context == null) {
throw new NullPointerException();
}
if (base == null || property == null) {
return false;
}
context.setPropertyResolved(true);
return this.readOnly
|| this.property(context, base, property).isReadOnly();
}
public Iterator<FeatureDescriptor> getFeatureDescriptors(ELContext context, Object base) {
if (context == null) {
throw new NullPointerException();
}
if (base == null) {
return null;
}
try {
BeanInfo info = Introspector.getBeanInfo(base.getClass());
PropertyDescriptor[] pds = info.getPropertyDescriptors();
for (PropertyDescriptor pd : pds) {
pd.setValue(RESOLVABLE_AT_DESIGN_TIME, Boolean.TRUE);
pd.setValue(TYPE, pd.getPropertyType());
}
return Arrays.asList((FeatureDescriptor[]) pds).iterator();
} catch (IntrospectionException e) {
//
}
return null;
}
public Class<?> getCommonPropertyType(ELContext context, Object base) {
if (context == null) {
throw new NullPointerException();
}
if (base != null) {
return Object.class;
}
return null;
}
protected final static class BeanProperties {
private final Map<String, BeanProperty> properties;
private final Class<?> type;
public BeanProperties(Class<?> type) throws ELException {
this.type = type;
this.properties = new HashMap<String, BeanProperty>();
try {
BeanInfo info = Introspector.getBeanInfo(this.type);
PropertyDescriptor[] pds = info.getPropertyDescriptors();
for (PropertyDescriptor pd : pds) {
this.properties.put(pd.getName(), new BeanProperty(
type, pd));
}
} catch (IntrospectionException ie) {
throw new ELException(ie);
}
}
private BeanProperty get(ELContext ctx, String name) {
BeanProperty property = this.properties.get(name);
if (property == null) {
throw new PropertyNotFoundException(message(ctx,
"propertyNotFound",
new Object[] { type.getName(), name }));
}
return property;
}
public BeanProperty getBeanProperty(String name) {
return get(null, name);
}
private Class<?> getType() {
return type;
}
}
protected final static class BeanProperty {
private final Class<?> type;
private final Class<?> owner;
private final PropertyDescriptor descriptor;
private Method read;
private Method write;
public BeanProperty(Class<?> owner, PropertyDescriptor descriptor) {
this.owner = owner;
this.descriptor = descriptor;
this.type = descriptor.getPropertyType();
}
public Class getPropertyType() {
return this.type;
}
public boolean isReadOnly() {
return this.write == null
&& (null == (this.write = getMethod(this.owner, descriptor.getWriteMethod())));
}
public Method getWriteMethod() {
return write(null);
}
public Method getReadMethod() {
return this.read(null);
}
private Method write(ELContext ctx) {
if (this.write == null) {
this.write = getMethod(this.owner, descriptor.getWriteMethod());
if (this.write == null) {
throw new PropertyNotFoundException(message(ctx,
"propertyNotWritable", new Object[] {
type.getName(), descriptor.getName() }));
}
}
return this.write;
}
private Method read(ELContext ctx) {
if (this.read == null) {
this.read = getMethod(this.owner, descriptor.getReadMethod());
if (this.read == null) {
throw new PropertyNotFoundException(message(ctx,
"propertyNotReadable", new Object[] {
type.getName(), descriptor.getName() }));
}
}
return this.read;
}
}
private BeanProperty property(ELContext ctx, Object base,
Object property) {
Class<?> type = base.getClass();
String prop = property.toString();
BeanProperties props = this.cache.get(type.getName());
if (props == null || type != props.getType()) {
props = new BeanProperties(type);
this.cache.put(type.getName(), props);
}
return props.get(ctx, prop);
}
private static Method getMethod(Class type, Method m) {
if (m == null || Modifier.isPublic(type.getModifiers())) {
return m;
}
Class[] inf = type.getInterfaces();
Method mp;
for (Class anInf : inf) {
try {
mp = anInf.getMethod(m.getName(), (Class[]) m.getParameterTypes());
mp = getMethod(mp.getDeclaringClass(), mp);
if (mp != null) {
return mp;
}
} catch (NoSuchMethodException e) {
//continue
}
}
Class sup = type.getSuperclass();
if (sup != null) {
try {
mp = sup.getMethod(m.getName(), (Class[]) m.getParameterTypes());
mp = getMethod(mp.getDeclaringClass(), mp);
if (mp != null) {
return mp;
}
} catch (NoSuchMethodException e) {
//continue
}
}
return null;
}
private final static class ConcurrentCache<K,V> {
private final int size;
private final Map<K,V> eden;
private final Map<K,V> longterm;
public ConcurrentCache(int size) {
this.size = size;
this.eden = new ConcurrentHashMap<K,V>(size);
this.longterm = new WeakHashMap<K,V>(size);
}
public V get(K key) {
V value = this.eden.get(key);
if (value == null) {
value = this.longterm.get(key);
if (value != null) {
this.eden.put(key, value);
}
}
return value;
}
public void put(K key, V value) {
if (this.eden.size() >= this.size) {
this.longterm.putAll(this.eden);
this.eden.clear();
}
this.eden.put(key, value);
}
}
}