/*
*
* * Copyright 2014 Orient Technologies LTD (info(at)orientechnologies.com)
* *
* * 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.
* *
* * For more information: http://www.orientechnologies.com
*
*/
package com.orientechnologies.orient.object.db;
import java.io.Serializable;
import java.util.Iterator;
import javassist.util.proxy.ProxyObject;
import com.orientechnologies.common.log.OLogManager;
import com.orientechnologies.orient.core.db.record.ODatabaseRecord;
import com.orientechnologies.orient.core.db.record.OIdentifiable;
import com.orientechnologies.orient.core.id.ORID;
import com.orientechnologies.orient.core.record.ORecord;
import com.orientechnologies.orient.core.record.impl.ODocument;
import com.orientechnologies.orient.object.enhancement.OObjectEntitySerializer;
import com.orientechnologies.orient.object.enhancement.OObjectProxyMethodHandler;
/**
* Lazy implementation of Iterator that load the records only when accessed. It keep also track of changes to the source record
* avoiding to call setDirty() by hand.
*
* @author Luca Garulli (l.garulli--at--orientechnologies.com)
*
*/
@SuppressWarnings({ "unchecked" })
public class OObjectLazyIterator<TYPE> implements Iterator<TYPE>, Serializable {
private static final long serialVersionUID = -4012483076050044405L;
private final ProxyObject sourceRecord;
private final ODatabasePojoAbstract<TYPE> database;
private final Iterator<? extends Object> underlying;
private String fetchPlan;
final private boolean autoConvert2Object;
private OIdentifiable currentElement;
private boolean orphanRemoval = false;
public OObjectLazyIterator(final ODatabasePojoAbstract<TYPE> database, final ProxyObject iSourceRecord,
final Iterator<? extends Object> iIterator, final boolean iConvertToRecord, boolean iOrphanRemoval) {
this.database = database;
this.sourceRecord = iSourceRecord;
this.underlying = iIterator;
autoConvert2Object = iConvertToRecord;
this.orphanRemoval = iOrphanRemoval;
}
public TYPE next() {
return next(fetchPlan);
}
public TYPE next(final String iFetchPlan) {
final Object value = underlying.next();
if (value == null)
return null;
if (value instanceof ORID && autoConvert2Object) {
currentElement = (OIdentifiable) value;
ORecord record = (ORecord) ((ODatabaseRecord) database.getUnderlying()).load((ORID) value, iFetchPlan);
if (record == null) {
OLogManager.instance().warn(
this,
"Record " + ((OObjectProxyMethodHandler) sourceRecord.getHandler()).getDoc().getIdentity()
+ " references a deleted instance");
return null;
}
TYPE o = database.getUserObjectByRecord(record, iFetchPlan);
((OObjectProxyMethodHandler) (((ProxyObject) o)).getHandler()).setParentObject(sourceRecord);
return o;
} else if (value instanceof ODocument && autoConvert2Object) {
currentElement = (OIdentifiable) value;
TYPE o = database.getUserObjectByRecord((ODocument) value, iFetchPlan);
((OObjectProxyMethodHandler) (((ProxyObject) o)).getHandler()).setParentObject(sourceRecord);
return o;
} else {
currentElement = database.getRecordByUserObject(value, false);
}
if (OObjectEntitySerializer.isToSerialize(value.getClass()))
return (TYPE) OObjectEntitySerializer.deserializeFieldValue(value.getClass(), value);
return (TYPE) value;
}
public boolean hasNext() {
return underlying.hasNext();
}
public void remove() {
underlying.remove();
if (sourceRecord != null) {
if (orphanRemoval)
((OObjectProxyMethodHandler) sourceRecord.getHandler()).getOrphans().add(currentElement.getIdentity());
((OObjectProxyMethodHandler) sourceRecord.getHandler()).setDirty();
}
}
public String getFetchPlan() {
return fetchPlan;
}
public void setFetchPlan(String fetchPlan) {
this.fetchPlan = fetchPlan;
}
}