NotFoundELResolver.java
/*
* 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 jakarta.servlet.jsp.el;
import java.util.Objects;
import java.util.ResourceBundle;
import jakarta.el.ELContext;
import jakarta.el.ELResolver;
import jakarta.el.PropertyNotFoundException;
/**
* The final resolver of the Jakarta Pages ELResolver chain. It always resolves the requested value, returning
* {@code null} when it does so.
*
* @since JSP 3.1
*/
public class NotFoundELResolver extends ELResolver {
private static final String LSTRING_FILE = "jakarta.servlet.jsp.LocalStrings";
private static final ResourceBundle lStrings = ResourceBundle.getBundle(LSTRING_FILE);
/**
* Default constructor.
*/
public NotFoundELResolver() {
super();
}
/**
* {@inheritDoc}
* <p>
* Resolves the property and always returns {@code null} unless the provided context contains a Boolean object with
* value {@code Boolean.TRUE} as the value associated with the key
* {@code jakarta.servlet.jsp.el.NotFoundELResolver.class} in which case an exception is thrown. This is to support
* implementation of the {@code errorOnELNotFound} page/tag directive.
*
* @return Always {@code null}
*
* @throws PropertyNotFoundException if the provided context contains a Boolean object with value
* {@code Boolean.TRUE} as the value associated with the key
* {@code jakarta.servlet.jsp.el.NotFoundELResolver.class}
*/
@Override
public Object getValue(ELContext context, Object base, Object property) {
Objects.requireNonNull(context);
Object obj = context.getContext(this.getClass());
if (obj instanceof Boolean && ((Boolean) obj).booleanValue()) {
throw new PropertyNotFoundException(
lStrings.getString("el.unknown.identifier") + " [" + property.toString() + "]");
}
context.setPropertyResolved(base, property);
return null;
}
/**
* {@inheritDoc}
* <p>
* In normal usage, {@link ScopedAttributeELResolver} will have responded.
*
* @return Always {@code null}
*/
@Override
public Class<Object> getType(ELContext context, Object base, Object property) {
Objects.requireNonNull(context);
return null;
}
/**
* {@inheritDoc}
* <p>
* No-op. In normal usage, {@link ScopedAttributeELResolver} will have responded.
*/
@Override
public void setValue(ELContext context, Object base, Object property, Object value) {
Objects.requireNonNull(context);
}
/**
* {@inheritDoc}
* <p>
* In normal usage, {@link ScopedAttributeELResolver} will have responded.
*
* @return Always {@code false}
*/
@Override
public boolean isReadOnly(ELContext context, Object base, Object property) {
Objects.requireNonNull(context);
return false;
}
/**
* {@inheritDoc}
* <p>
* In normal usage, {@link ScopedAttributeELResolver} will have responded.
*
* @return Always {@code null}
*/
@Override
public Class<String> getCommonPropertyType(ELContext context, Object base) {
return null;
}
}