org.apache.openjpa.jdbc.kernel.GenericResultObjectProvider Maven / Gradle / Ivy
/*
* 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.jdbc.kernel;
import java.sql.SQLException;
import org.apache.openjpa.jdbc.meta.ClassMapping;
import org.apache.openjpa.jdbc.sql.Result;
import org.apache.openjpa.jdbc.sql.SQLExceptions;
import org.apache.openjpa.kernel.StoreContext;
import org.apache.openjpa.lib.rop.ResultObjectProvider;
import org.apache.openjpa.util.StoreException;
import org.apache.openjpa.util.UnsupportedException;
/**
* Object provider implementation wrapped around a generic {@link Result}.
*
* @author Abe White
*/
public class GenericResultObjectProvider
implements ResultObjectProvider {
private final ClassMapping _mapping;
private final JDBCStore _store;
private final JDBCFetchConfiguration _fetch;
private final Result _res;
/**
* Constructor.
*
* @param pcClass the base class of the result objects
* @param store the store manager to delegate loading to
* @param fetch the fetch configuration, or null for default
* @param res the result containing the data
*/
public GenericResultObjectProvider(Class pcClass,
JDBCStore store, JDBCFetchConfiguration fetch, Result res) {
this(store.getConfiguration().getMappingRepositoryInstance().getMapping
(pcClass, store.getContext().getClassLoader(), true),
store, fetch, res);
}
/**
* Constructor.
*
* @param mapping the mapping for the base class of the result objects
* @param store the store manager to delegate loading to
* @param fetch the fetch configuration, or null for default
* @param res the result containing the data
*/
public GenericResultObjectProvider(ClassMapping mapping,
JDBCStore store, JDBCFetchConfiguration fetch, Result res) {
_mapping = mapping;
_store = store;
if (fetch == null)
_fetch = store.getFetchConfiguration();
else
_fetch = fetch;
_res = res;
}
public boolean supportsRandomAccess() {
try {
return _res.supportsRandomAccess();
} catch (Throwable t) {
return false;
}
}
public void open() {
}
public Object getResultObject()
throws SQLException {
// rather than use the standard result.load(), we go direct to
// the store manager so we can tell it not to load anything additional
return ((JDBCStoreManager) _store).load(_mapping, _fetch,
StoreContext.EXCLUDE_ALL, _res);
}
public boolean next()
throws SQLException {
return _res.next();
}
public boolean absolute(int pos)
throws SQLException {
return _res.absolute(pos);
}
public int size()
throws SQLException {
if (_fetch.getLRSSize() == LRSSizes.SIZE_UNKNOWN
|| !supportsRandomAccess())
return Integer.MAX_VALUE;
return _res.size();
}
public void reset() {
throw new UnsupportedException();
}
public void close() {
_res.close();
}
public void handleCheckedException(Exception e) {
if (e instanceof SQLException)
throw SQLExceptions.getStore((SQLException) e, _store.getDBDictionary(), _fetch.getReadLockLevel());
throw new StoreException(e);
}
}