/*
* Copyright 2006 The Apache Software Foundation.
*
* Licensed 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.FeatureDescriptor;
import java.lang.reflect.Array;
import java.util.Arrays;
import java.util.Iterator;
public class ArrayELResolver extends ELResolver {
private final boolean readOnly;
public ArrayELResolver() {
this.readOnly = false;
}
public ArrayELResolver(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 && base.getClass().isArray()) {
context.setPropertyResolved(true);
int idx = coerce(property);
checkBounds(base, idx);
return Array.get(base, idx);
}
return null;
}
public Class<?> getType(ELContext context, Object base, Object property)
throws NullPointerException, PropertyNotFoundException, ELException {
if (context == null) {
throw new NullPointerException();
}
if (base != null && base.getClass().isArray()) {
context.setPropertyResolved(true);
int idx = coerce(property);
checkBounds(base, idx);
return base.getClass().getComponentType();
}
return null;
}
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 && base.getClass().isArray()) {
context.setPropertyResolved(true);
if (this.readOnly) {
throw new PropertyNotWritableException(message(context,
"resolverNotWriteable", new Object[] { base.getClass()
.getName() }));
}
int idx = coerce(property);
checkBounds(base, idx);
Array.set(base, idx, value);
}
}
public boolean isReadOnly(ELContext context, Object base, Object property)
throws NullPointerException, PropertyNotFoundException, ELException {
if (context == null) {
throw new NullPointerException();
}
if (base != null && base.getClass().isArray()) {
context.setPropertyResolved(true);
int idx = coerce(property);
checkBounds(base, idx);
}
return this.readOnly;
}
public Iterator<FeatureDescriptor> getFeatureDescriptors(ELContext context, Object base) {
if (base != null && base.getClass().isArray()) {
FeatureDescriptor[] descs = new FeatureDescriptor[Array.getLength(base)];
for (int i = 0; i < descs.length; i++) {
descs[i] = new FeatureDescriptor();
descs[i].setDisplayName("["+i+"]");
descs[i].setExpert(false);
descs[i].setHidden(false);
descs[i].setName(""+i);
descs[i].setPreferred(true);
descs[i].setValue(RESOLVABLE_AT_DESIGN_TIME, Boolean.FALSE);
descs[i].setValue(TYPE, Integer.class);
}
return Arrays.asList(descs).iterator();
}
return null;
}
public Class<?> getCommonPropertyType(ELContext context, Object base) {
if (base != null && base.getClass().isArray()) {
return Integer.class;
}
return null;
}
private final static void checkBounds(Object base, int idx) {
if (idx < 0 || idx >= Array.getLength(base)) {
throw new PropertyNotFoundException(
new ArrayIndexOutOfBoundsException(idx).getMessage());
}
}
private final static int coerce(Object property) {
if (property instanceof Number) {
return ((Number) property).intValue();
}
if (property instanceof Character) {
return ((Character) property).charValue();
}
if (property instanceof Boolean) {
return (((Boolean) property).booleanValue() ? 1 : 0);
}
throw new IllegalArgumentException(property != null ? property
.toString() : "null");
}
}