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/* ====================================================================
*
* The ObjectStyle Group Software License, version 1.1
* ObjectStyle Group - http://objectstyle.org/
*
* Copyright (c) 2002-2005, Andrei (Andrus) Adamchik and individual authors
* of the software. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution, if any,
* must include the following acknowlegement:
* "This product includes software developed by independent contributors
* and hosted on ObjectStyle Group web site (http://objectstyle.org/)."
* Alternately, this acknowlegement may appear in the software itself,
* if and wherever such third-party acknowlegements normally appear.
*
* 4. The names "ObjectStyle Group" and "Cayenne" must not be used to endorse
* or promote products derived from this software without prior written
* permission. For written permission, email
* "andrus at objectstyle dot org".
*
* 5. Products derived from this software may not be called "ObjectStyle"
* or "Cayenne", nor may "ObjectStyle" or "Cayenne" appear in their
* names without prior written permission.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE OBJECTSTYLE GROUP OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals and hosted on ObjectStyle Group web site. For more
* information on the ObjectStyle Group, please see
*
* WARNING: this is a bit of a hack - it works for my toMany's, but it possibly
* doesn't work in all cases.
*
*
* *** It definitly does not work for compound keys ***
*
*/
public static void resolveToManyRelations(
DataContext context,
List objects,
String relName) {
int nobjects = objects.size();
if (nobjects == 0)
return;
String dbKey = null;
Map listMap = new HashMap(nobjects);
// put the object-ids in a map for later assignment of the
// query results
for (int i = 0; i < nobjects; i++) {
DataObject object = (DataObject) objects.get(i);
ObjectId oid = object.getObjectId();
if (dbKey == null) {
Map id = oid.getIdSnapshot();
if (id.size() != 1) {
throw new CayenneRuntimeException(
"resolveToManyRelations expects single keys for now...");
}
dbKey = (String) id.keySet().iterator().next();
}
listMap.put(oid.getValueForAttribute(dbKey), new ArrayList());
}
ObjEntity ent = context.getEntityResolver().lookupObjEntity(
(DataObject) objects.get(0));
ObjRelationship rel = (ObjRelationship) ent.getRelationship(relName);
ObjEntity destEnt = (ObjEntity) rel.getTargetEntity();
List dbRels = rel.getDbRelationships();
// sanity check
if (dbRels == null || dbRels.size() == 0) {
throw new CayenneRuntimeException("ObjRelationship '"
+ rel.getName()
+ "' is unmapped.");
}
// build a reverse DB path
// ...while reverse ObjRelationship may be absent,
// reverse DB must always be there...
StringBuffer buf = new StringBuffer();
ListIterator it = dbRels.listIterator(dbRels.size());
while (it.hasPrevious()) {
if (buf.length() > 0) {
buf.append(".");
}
DbRelationship dbRel = (DbRelationship) it.previous();
DbRelationship reverse = dbRel.getReverseRelationship();
// another sanity check
if (reverse == null) {
throw new CayenneRuntimeException("DbRelatitionship '"
+ dbRel.getName()
+ "' has no reverse relationship");
}
buf.append(reverse.getName());
}
// do the query
ASTDbPath dbpath = new ASTDbPath(buf.toString());
ASTList listExp = new ASTList(objects);
SelectQuery sel = new SelectQuery(destEnt, new ASTIn(dbpath, listExp));
sel.setFetchingDataRows(true);
List results = context.performQuery(sel);
// sort the resulting objects into individual lists for each source object
List destObjects = context.objectsFromDataRows(destEnt, results, false, false);
int nrows = destObjects.size();
for (int k = 0; k < nrows; k++) {
Map row = (Map) results.get(k);
((List) listMap.get(row.get(dbKey))).add(destObjects.get(k));
}
// and finally set these lists in the relation targets
for (int i = 0; i < nobjects; i++) {
DataObject object = (DataObject) objects.get(i);
ObjectId oid = object.getObjectId();
Object list = listMap.get(oid.getValueForAttribute(dbKey));
((ValueHolder) object.readPropertyDirectly(relName)).setValueDirectly(list);
}
}
}