/*
* 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 org.zkoss.zel;
import java.beans.FeatureDescriptor;
import java.lang.reflect.Constructor;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.util.Iterator;
/**
* @since EL 3.0
*/
public class StaticFieldELResolver extends ELResolver {
public Object getValue(ELContext context, Object base, Object property) {
if (context == null) {
throw new NullPointerException();
}
if (base instanceof ELClass && property instanceof String) {
context.setPropertyResolved(base, property);
Class<?> clazz = ((ELClass) base).getKlass();
String name = (String) property;
Exception exception = null;
try {
Field field = clazz.getField(name);
int modifiers = field.getModifiers();
if (Modifier.isStatic(modifiers) &&
Modifier.isPublic(modifiers)) {
return field.get(null);
}
} catch (IllegalArgumentException e) {
exception = e;
} catch (IllegalAccessException e) {
exception = e;
} catch (NoSuchFieldException e) {
exception = e;
} catch (SecurityException e) {
exception = e;
}
String msg = Util.message(context, "staticFieldELResolver.notFound",
name, clazz.getName());
if (exception == null) {
throw new PropertyNotFoundException(msg);
} else {
throw new PropertyNotFoundException(msg, exception);
}
}
return null;
}
public void setValue(ELContext context, Object base, Object property,
Object value) {
if (context == null) {
throw new NullPointerException();
}
if (base instanceof ELClass && property instanceof String) {
Class<?> clazz = ((ELClass) base).getKlass();
String name = (String) property;
throw new PropertyNotWritableException(Util.message(context,
"staticFieldELResolver.notWriteable", name,
clazz.getName()));
}
}
public Object invoke(ELContext context, Object base, Object method,
Class<?>[] paramTypes, Object[] params) {
if (context == null) {
throw new NullPointerException();
}
if (base instanceof ELClass && method instanceof String) {
context.setPropertyResolved(base, method);
Class<?> clazz = ((ELClass) base).getKlass();
String methodName = (String) method;
if ("<init>".equals(methodName)) {
Constructor<?> match =
Util.findConstructor(clazz, paramTypes, params);
Object[] parameters = Util.buildParameters(
match.getParameterTypes(), match.isVarArgs(), params);
Object result = null;
try {
result = match.newInstance(parameters);
} catch (IllegalArgumentException e) {
throw new ELException(e);
} catch (IllegalAccessException e) {
throw new ELException(e);
} catch (InstantiationException e) {
throw new ELException(e);
} catch (InvocationTargetException e) {
Throwable cause = e.getCause();
Util.handleThrowable(cause);
throw new ELException(cause);
}
return result;
} else {
Method match =
Util.findMethod(clazz, methodName, paramTypes, params);
int modifiers = match.getModifiers();
if (!Modifier.isStatic(modifiers)) {
throw new MethodNotFoundException(Util.message(context,
"staticFieldELResolver.methodNotFound", methodName,
clazz.getName()));
}
Object[] parameters = Util.buildParameters(
match.getParameterTypes(), match.isVarArgs(), params);
Object result = null;
try {
result = match.invoke(null, parameters);
} catch (IllegalArgumentException e) {
throw new ELException(e);
} catch (IllegalAccessException e) {
throw new ELException(e);
} catch (InvocationTargetException e) {
Throwable cause = e.getCause();
Util.handleThrowable(cause);
throw new ELException(cause);
}
return result;
}
}
return null;
}
public Class<?> getType(ELContext context, Object base, Object property) {
if (context == null) {
throw new NullPointerException();
}
if (base instanceof ELClass && property instanceof String) {
context.setPropertyResolved(base, property);
Class<?> clazz = ((ELClass) base).getKlass();
String name = (String) property;
Exception exception = null;
try {
Field field = clazz.getField(name);
int modifiers = field.getModifiers();
if (Modifier.isStatic(modifiers) &&
Modifier.isPublic(modifiers)) {
return field.getType();
}
} catch (IllegalArgumentException e) {
exception = e;
} catch (NoSuchFieldException e) {
exception = e;
} catch (SecurityException e) {
exception = e;
}
String msg = Util.message(context, "staticFieldELResolver.notFound",
name, clazz.getName());
if (exception == null) {
throw new PropertyNotFoundException(msg);
} else {
throw new PropertyNotFoundException(msg, exception);
}
}
return null;
}
public boolean isReadOnly(ELContext context, Object base, Object property) {
if (context == null) {
throw new NullPointerException();
}
if (base instanceof ELClass && property instanceof String) {
context.setPropertyResolved(base, property);
}
return true;
}
/**
* Always returns <code>null</code>.
*/
public Iterator<FeatureDescriptor> getFeatureDescriptors(ELContext context,
Object base) {
return null;
}
/**
* Always returns <code>String.class</code>.
*/
public Class<?> getCommonPropertyType(ELContext context, Object base) {
return String.class;
}
}