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* 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
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* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
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package org.apache.cayenne.access.translator.ejbql;
import java.util.Iterator;
import org.apache.cayenne.map.DbEntity;
import org.apache.cayenne.map.DbRelationship;
import org.apache.cayenne.reflect.ClassDescriptor;
import org.apache.cayenne.util.Util;
/**
* A helper class representing an "id" of a database table during EJBQL translation. EJBQL
* "ids" point to ObjEntities, but during translation we need id's that represent both
* "root" tables that map back to an ObjEntity, as well as joined tables for flattened
* attributes and relationships. EJBQLTableId is intended to represent both types of
* tables.
*
* @since 3.0
*/
class EJBQLTableId {
private static String appendPath(EJBQLTableId baseId, String dbPathSuffix) {
if (baseId.getDbPath() == null) {
return dbPathSuffix;
}
if (dbPathSuffix == null) {
return baseId.getDbPath();
}
return baseId.getDbPath() + "." + dbPathSuffix;
}
private String entityId;
private String dbPath;
EJBQLTableId(String entityId) {
this(entityId, null);
}
EJBQLTableId(EJBQLTableId baseId, String dbPathSuffix) {
this(baseId.getEntityId(), appendPath(baseId, dbPathSuffix));
}
EJBQLTableId(String entityId, String dbPath) {
if (entityId == null) {
throw new NullPointerException("Null entityId");
}
this.entityId = entityId;
this.dbPath = dbPath;
}
boolean isPrimaryTable() {
return dbPath == null;
}
/**
* Returns a DbEntity corresponding to the ID, that could be a root entity for the id,
* or a joined entity.
*/
DbEntity getDbEntity(EJBQLTranslationContext context) {
ClassDescriptor descriptor = context.getEntityDescriptor(entityId);
DbEntity rootEntity = descriptor.getEntity().getDbEntity();
if (dbPath == null) {
return rootEntity;
}
DbRelationship r = null;
Iterator<?> it = rootEntity.resolvePathComponents(dbPath);
while (it.hasNext()) {
r = (DbRelationship) it.next();
}
return (DbEntity) r.getTargetEntity();
}
String getEntityId() {
return entityId;
}
String getDbPath() {
return dbPath;
}
@Override
public int hashCode() {
int hash = entityId.hashCode();
if (dbPath != null) {
hash += dbPath.hashCode() * 7;
}
return hash;
}
@Override
public boolean equals(Object object) {
if (this == object) {
return true;
}
if (!(object instanceof EJBQLTableId)) {
return false;
}
EJBQLTableId id = (EJBQLTableId) object;
if (!Util.nullSafeEquals(entityId, id.entityId)) {
return false;
}
if (!Util.nullSafeEquals(dbPath, id.dbPath)) {
return false;
}
return true;
}
@Override
public String toString() {
return dbPath != null ? entityId + "/" + dbPath : entityId;
}
}