/* * Copyright 2016 Red Hat, Inc. and/or its affiliates * and other contributors as indicated by the @author tags. * * 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.keycloak.models.utils.reflection; 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() { Map<String, Property<V>> results = getResultList(); return results.isEmpty() ? null : results.values().iterator().next(); } /** * 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() { Map<String, Property<V>> results = getWritableResultList(); return results.isEmpty() ? null : results.values().iterator().next(); } /** * 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() { Map<String, Property<V>> results = getResultList(); if (results.size() == 1) { return results.values().iterator().next(); } 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() { Map<String, Property<V>> results = getWritableResultList(); if (results.size() == 1) { return results.values().iterator().next(); } 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 Map<String, 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 Map<String, 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 Map<String, Property<V>> getResultList(boolean writable) { Map<String, Property<V>> properties = new HashMap<String, Property<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()) { properties.put(property.getName(), property); } } } return Collections.unmodifiableMap(properties); } }