/*
* 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.apache.ambari.server.collections.functors;
import java.util.Collections;
import java.util.Map;
import org.apache.ambari.server.collections.Predicate;
import org.apache.commons.collections.functors.PredicateDecorator;
/**
* DelegatedSinglePredicateContainer is an abstract class providing functionality to managing a
* delegate used to hold a since {@link Predicate}s. For example <code>not</code>.
*/
abstract class DelegatedSinglePredicateContainer extends Predicate implements PredicateDecorator {
/**
* The delegate {@link PredicateDecorator} used to handle the internal logic for the container
*/
private final PredicateDecorator delegate;
/**
* Constructor.
*
* @param name the name of this predicate
* @param delegate the delegate used to handle the internal logic for the container
*/
DelegatedSinglePredicateContainer(String name, PredicateDecorator delegate) {
super(name);
this.delegate = delegate;
}
@Override
public Map<String, Object> toMap() {
return Collections.<String, Object>singletonMap(getName(), containedPredicateToMap());
}
@Override
public boolean evaluate(Object o) {
return delegate.evaluate(o);
}
@Override
public org.apache.commons.collections.Predicate[] getPredicates() {
return delegate.getPredicates();
}
@Override
public int hashCode() {
return super.hashCode() + ((delegate == null) ? 0 : delegate.hashCode());
}
@Override
public boolean equals(Object obj) {
if (obj == this) {
return true;
} else if (obj == null) {
return false;
} else if (super.equals(obj) && (obj instanceof DelegatedSinglePredicateContainer) && (hashCode() == obj.hashCode())) {
DelegatedSinglePredicateContainer p = (DelegatedSinglePredicateContainer) obj;
return (delegate == null) ? (p.delegate == null) : delegate.equals(p.delegate);
} else {
return false;
}
}
/**
* Processes the contained predicate into a Map.
* <p>
* This is used to serialize this {@link DelegatedSinglePredicateContainer} into a {@link Map}
*
* @return a map representing the contained predicate
*/
private Map<String, Object> containedPredicateToMap() {
Map<String, Object> map = null;
if (delegate != null) {
org.apache.commons.collections.Predicate[] predicates = delegate.getPredicates();
if ((predicates != null) && (predicates.length > 0)) {
// Only process the 1st predicate.
org.apache.commons.collections.Predicate p = predicates[0];
if (p instanceof Predicate) {
map = ((Predicate) p).toMap();
} else {
throw new UnsupportedOperationException(String.format("Cannot convert a %s to a Map", p.getClass().getName()));
}
}
}
return map;
}
}