/*
* JBoss, Home of Professional Open Source
*
* Copyright 2013 Red Hat, Inc. and/or its affiliates.
*
* 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 org.picketlink.common.properties.query;
import org.picketlink.common.properties.FieldProperty;
import org.picketlink.common.properties.MethodProperty;
import org.picketlink.common.properties.Properties;
import org.picketlink.common.properties.Property;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
/**
* <p> Queries a target class for properties that match certain criteria. A property may either be a private or public
* field, declared by the target class or inherited from a superclass, or a public method declared by the target class
* or inherited from any of its superclasses. For properties that are exposed via a method, the property must be a
* JavaBean style property, i.e. it must provide both an accessor and mutator method according to the JavaBean
* specification. </p> <p/> <p> This class is not thread-safe, however the result returned by the getResultList() method
* is. </p>
*
* @see PropertyQueries
* @see PropertyCriteria
*/
public class PropertyQuery<V> {
private final Class<?> targetClass;
private final List<PropertyCriteria> criteria;
PropertyQuery(Class<?> targetClass) {
if (targetClass == null) {
throw new IllegalArgumentException("targetClass parameter may not be null");
}
this.targetClass = targetClass;
this.criteria = new ArrayList<PropertyCriteria>();
}
/**
* Add a criteria to query
*
* @param criteria the criteria to add
*/
public PropertyQuery<V> addCriteria(PropertyCriteria criteria) {
this.criteria.add(criteria);
return this;
}
/**
* Get the first result from the query, causing the query to be run.
*
* @return the first result, or null if there are no results
*/
public Property<V> getFirstResult() {
List<Property<V>> results = getResultList();
return results.isEmpty() ? null : results.get(0);
}
/**
* Get the first result from the query that is not marked as read only, causing the query to be run.
*
* @return the first writable result, or null if there are no results
*/
public Property<V> getFirstWritableResult() {
List<Property<V>> results = getWritableResultList();
return results.isEmpty() ? null : results.get(0);
}
/**
* Get a single result from the query, causing the query to be run. An exception is thrown if the query does not
* return exactly one result.
*
* @return the single result
*
* @throws RuntimeException if the query does not return exactly one result
*/
public Property<V> getSingleResult() {
List<Property<V>> results = getResultList();
if (results.size() == 1) {
return results.get(0);
} else if (results.isEmpty()) {
throw new RuntimeException(
"Expected one property match, but the criteria did not match any properties on " +
targetClass.getName());
} else {
throw new RuntimeException("Expected one property match, but the criteria matched " + results.size() +
" properties on " + targetClass.getName());
}
}
/**
* Get a single result from the query that is not marked as read only, causing the query to be run. An exception is
* thrown if the query does not return exactly one result.
*
* @return the single writable result
*
* @throws RuntimeException if the query does not return exactly one result
*/
public Property<V> getWritableSingleResult() {
List<Property<V>> results = getWritableResultList();
if (results.size() == 1) {
return results.get(0);
} else if (results.isEmpty()) {
throw new RuntimeException(
"Expected one property match, but the criteria did not match any properties on " +
targetClass.getName());
} else {
throw new RuntimeException("Expected one property match, but the criteria matched " +
results.size() + " properties on " + targetClass.getName());
}
}
/**
* Get the result from the query, causing the query to be run.
*
* @return the results, or an empty list if there are no results
*/
public List<Property<V>> getResultList() {
return getResultList(false);
}
/**
* Get the non read only results from the query, causing the query to be run.
*
* @return the results, or an empty list if there are no results
*/
public List<Property<V>> getWritableResultList() {
return getResultList(true);
}
/**
* Get the result from the query, causing the query to be run.
*
* @param writable if this query should only return properties that are not read only
*
* @return the results, or an empty list if there are no results
*/
private List<Property<V>> getResultList(boolean writable) {
Map<String, PropertyAdapter<V>> adapters = new HashMap<String, PropertyAdapter<V>>();
// First check public accessor methods (we ignore private methods)
for (Method method : targetClass.getMethods()) {
if (!(method.getName().startsWith("is") || method.getName().startsWith("get"))) {
continue;
}
boolean match = true;
for (PropertyCriteria c : criteria) {
if (!c.methodMatches(method)) {
match = false;
break;
}
}
if (match) {
MethodProperty<V> property = Properties.<V>createProperty(method);
if (!writable || !property.isReadOnly()) {
adapters.put(property.getName(), new PropertyAdapter<V>(property));
}
}
}
Class<?> cls = targetClass;
while (cls != null && !cls.equals(Object.class)) {
// Now check declared fields
for (Field field : cls.getDeclaredFields()) {
boolean match = true;
for (PropertyCriteria c : criteria) {
if (!c.fieldMatches(field)) {
match = false;
break;
}
}
FieldProperty<V> prop = Properties.<V>createProperty(field);
if (match) {
if (!writable || !prop.isReadOnly()) {
PropertyAdapter<V> adapter = adapters.get(prop.getName());
if (adapter != null) {
adapter.setProperty(prop);
} else {
adapter = new PropertyAdapter<V>(prop);
}
adapters.put(adapter.getName(), adapter);
}
}
}
cls = cls.getSuperclass();
}
return Collections.unmodifiableList(new ArrayList<Property<V>>(adapters.values()));
}
}