| /* |
| * 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.openjpa.meta; |
| |
| import java.util.Comparator; |
| |
| import org.apache.openjpa.enhance.PersistenceCapable; |
| import org.apache.openjpa.kernel.OpenJPAStateManager; |
| import org.apache.openjpa.util.ApplicationIds; |
| import org.apache.openjpa.util.ImplHelper; |
| import org.apache.openjpa.conf.OpenJPAConfiguration; |
| |
| /** |
| * Order by the field value in memory. If the field contains |
| * {@link PersistenceCapable} objects, order on their primary key values. |
| * Relies on primary key values, including datastore oid objects, being |
| * {@link Comparable}. |
| * |
| * @author Abe White |
| */ |
| class InMemoryValueOrder |
| implements Order, Comparator { |
| |
| private final boolean _asc; |
| private final OpenJPAConfiguration _conf; |
| |
| public InMemoryValueOrder(boolean asc, OpenJPAConfiguration conf) { |
| _asc = asc; |
| _conf = conf; |
| } |
| |
| public String getName() { |
| return Order.ELEMENT; |
| } |
| |
| public boolean isAscending() { |
| return _asc; |
| } |
| |
| public Comparator getComparator() { |
| return this; |
| } |
| |
| public int compare(Object o1, Object o2) { |
| if (o1 == o2) |
| return 0; |
| if (o1 == null) |
| return (_asc) ? -1 : 1; |
| if (o2 == null) |
| return (_asc) ? 1 : -1; |
| |
| // non-pc values must be comparable |
| int cmp; |
| if (!(ImplHelper.isManageable(o1)) |
| || !(ImplHelper.isManageable(o2))) { |
| cmp = ((Comparable) o1).compareTo(o2); |
| return (_asc) ? cmp : -cmp; |
| } |
| |
| // order on primary key values |
| PersistenceCapable pc1 = ImplHelper.toPersistenceCapable(o1, _conf); |
| PersistenceCapable pc2 = ImplHelper.toPersistenceCapable(o2, _conf); |
| OpenJPAStateManager sm1 = (OpenJPAStateManager) pc1.pcGetStateManager(); |
| OpenJPAStateManager sm2 = (OpenJPAStateManager) pc2.pcGetStateManager(); |
| if (sm1 == null || sm2 == null) |
| return 0; |
| |
| Object[] pk1 = toPKValues(sm1); |
| Object[] pk2 = toPKValues(sm2); |
| int len = Math.min(pk1.length, pk2.length); |
| for (int i = 0; i < len; i++) { |
| if (pk1[i] == pk2[i]) |
| return 0; |
| if (pk1[i] == null) |
| return (_asc) ? -1 : 1; |
| if (pk2[i] == null) |
| return (_asc) ? 1 : -1; |
| cmp = ((Comparable) pk1[i]).compareTo(pk2[i]); |
| if (cmp != 0) |
| return (_asc) ? cmp : -cmp; |
| } |
| |
| cmp = pk1.length - pk2.length; |
| return (_asc) ? cmp : -cmp; |
| } |
| |
| /** |
| * Convert the given state manager's oid to an array of (possibly null) |
| * primary key values. |
| */ |
| private static Object[] toPKValues(OpenJPAStateManager sm) { |
| if (sm.getMetaData().getIdentityType() != ClassMetaData.ID_APPLICATION) |
| return new Object[]{ sm.getObjectId() }; |
| |
| Object[] pks = ApplicationIds.toPKValues(sm.getObjectId(), |
| sm.getMetaData()); |
| if (pks == null) |
| pks = new Object[]{ null }; |
| return pks; |
| } |
| } |