/*
* 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.meta.strats;
import java.sql.SQLException;
import org.apache.openjpa.jdbc.identifier.DBIdentifier;
import org.apache.openjpa.jdbc.kernel.JDBCFetchConfiguration;
import org.apache.openjpa.jdbc.kernel.JDBCStore;
import org.apache.openjpa.jdbc.meta.ClassMapping;
import org.apache.openjpa.jdbc.meta.RelationId;
import org.apache.openjpa.jdbc.meta.ValueHandler;
import org.apache.openjpa.jdbc.meta.ValueMapping;
import org.apache.openjpa.jdbc.meta.ValueMappingInfo;
import org.apache.openjpa.jdbc.schema.Column;
import org.apache.openjpa.jdbc.schema.ColumnIO;
import org.apache.openjpa.jdbc.sql.DBDictionary;
import org.apache.openjpa.jdbc.sql.Joins;
import org.apache.openjpa.jdbc.sql.Result;
import org.apache.openjpa.jdbc.sql.Row;
import org.apache.openjpa.kernel.OpenJPAStateManager;
import org.apache.openjpa.lib.util.Localizer;
import org.apache.openjpa.util.InvalidStateException;
/**
* Utility methods for strategies using value handlers.
*
* @author Abe White
* @since 0.4.0
*/
public class HandlerStrategies {
private static final Localizer _loc = Localizer.forPackage
(HandlerStrategies.class);
/**
* Map the given value.
*/
public static Column[] map(ValueMapping vm, String name, ColumnIO io,
boolean adapt) {
ValueMappingInfo vinfo = vm.getValueInfo();
vinfo.assertNoJoin(vm, true);
vinfo.assertNoForeignKey(vm, !adapt);
DBDictionary dict = vm.getMappingRepository().getDBDictionary();
DBIdentifier colName = DBIdentifier.newColumn(name, dict != null ? dict.delimitAll() : false);
Column[] cols = vm.getHandler().map(vm, colName.getName(), io, adapt);
if (cols.length > 0 && cols[0].getTable() == null) {
cols = vinfo.getColumns(vm, colName, cols,
vm.getFieldMapping().getTable(), adapt);
if (vinfo.isImplicitRelation())
for (int i = 0; i < cols.length; i++)
cols[i].setImplicitRelation(true);
ColumnIO mappedIO = vinfo.getColumnIO();
vm.setColumns(cols);
vm.setColumnIO(mappedIO);
if (mappedIO != null) {
for (int i = 0; i < cols.length; i++) {
io.setInsertable(i, mappedIO.isInsertable(i, false));
io.setNullInsertable(i, mappedIO.isInsertable(i, true));
io.setUpdatable(i, mappedIO.isUpdatable(i, false));
io.setNullUpdatable(i, mappedIO.isUpdatable(i, true));
}
}
}
vm.mapConstraints(colName, adapt);
return cols;
}
/**
* Set the given value into the given row.
* Return false if the given value can not be set, for example, due to
* null constraints on the columns.
*/
public static boolean set(ValueMapping vm, Object val, JDBCStore store,
Row row, Column[] cols, ColumnIO io, boolean nullNone)
throws SQLException {
if (!canSetAny(row, io, cols))
return false;
ValueHandler handler = vm.getHandler();
val = handler.toDataStoreValue(vm, val, store);
boolean isSet = false;
if (val == null) {
for (int i = 0; i < cols.length; i++)
if (canSet(row, io, i, true)) {
isSet = true;
set(row, cols[i], null, handler, nullNone);
}
} else if (cols.length == 1) {
if (canSet(row, io, 0, val == null)) {
isSet = true;
set(row, cols[0], val, handler, nullNone);
}
} else {
Object[] vals = (Object[]) val;
for (int i = 0; i < vals.length; i++)
if (canSet(row, io, i, vals[i] == null)) {
isSet = true;
set(row, cols[i], vals[i], handler, nullNone);
}
}
return isSet;
}
/**
* Return true if the given column index is settable.
*/
private static boolean canSet(Row row, ColumnIO io, int i,
boolean nullValue) {
if (row.getAction() == Row.ACTION_INSERT)
return io.isInsertable(i, nullValue);
if (row.getAction() == Row.ACTION_UPDATE)
return io.isUpdatable(i, nullValue);
return true;
}
/**
* Return true if the any column up to the given index is settable.
*/
private static boolean canSetAny(Row row, ColumnIO io, Column[] cols) {
if (row.getAction() == Row.ACTION_INSERT)
return io.isAnyInsertable(cols, false);
if (row.getAction() == Row.ACTION_UPDATE)
return io.isAnyUpdatable(cols, false);
return true;
}
/**
* Set a value into a row, taking care not to override column defaults
* with nulls unless the user wants us to.
*/
private static void set(Row row, Column col, Object val,
ValueHandler handler, boolean nullNone)
throws SQLException {
if (val == null)
row.setNull(col, nullNone);
else if (col.isRelationId() && handler instanceof RelationId)
row.setRelationId(col, (OpenJPAStateManager) val,
(RelationId) handler);
else
row.setObject(col, val);
}
/**
* Add where conditions to the given row.
*/
public static void where(ValueMapping vm, Object val, JDBCStore store,
Row row, Column[] cols)
throws SQLException {
if (cols.length == 0)
return;
val = toDataStoreValue(vm, val, cols, store);
if (val == null)
for (int i = 0; i < cols.length; i++)
row.whereNull(cols[i]);
else if (cols.length == 1)
where(row, cols[0], val);
else {
Object[] vals = (Object[]) val;
for (int i = 0; i < vals.length; i++)
where(row, cols[i], vals[i]);
}
}
/**
* Set a where condition on the given row.
*/
private static void where(Row row, Column col, Object val)
throws SQLException {
if (val == null)
row.whereNull(col);
else
row.whereObject(col, val);
}
/**
* Load the Object value from the given result.
*/
public static Object loadObject(ValueMapping vm, OpenJPAStateManager sm,
JDBCStore store, JDBCFetchConfiguration fetch, Result res,
Joins joins, Column[] cols, boolean objectValueRequiresLoad)
throws SQLException {
if (cols.length == 0)
throw new InvalidStateException(_loc.get("cant-project-owned",
vm));
Object val = loadDataStore(vm, res, joins, cols);
if (objectValueRequiresLoad)
return vm.getHandler().toObjectValue(vm, val, sm, store, fetch);
return vm.getHandler().toObjectValue(vm, val);
}
/**
* Load the datastore value from the given result. This method does
* <b>not</b> process the loaded value through
* {@link ValueHandler#toObjectValue}.
*/
public static Object loadDataStore(ValueMapping vm, Result res,
Joins joins, Column[] cols)
throws SQLException {
if (cols.length == 0)
return null;
if (cols.length == 1)
return res.getObject(cols[0], vm.getHandler().
getResultArgument(vm), joins);
Object[] vals = new Object[cols.length];
Object[] args = (Object[]) vm.getHandler().getResultArgument(vm);
for (int i = 0; i < cols.length; i++)
vals[i] = res.getObject(cols[i], (args == null) ? null : args[i],
joins);
return vals;
}
/**
* Convert the given object to its datastore value(s). Relation ids are
* converted to their final values immediately.
*/
public static Object toDataStoreValue(ValueMapping vm, Object val,
Column[] cols, JDBCStore store) {
ValueHandler handler = vm.getHandler();
val = handler.toDataStoreValue(vm, val, store);
if (val == null) {
if (cols.length > 1)
return new Object[cols.length];
return null;
}
// relation ids are returned as state managers; resolve the final
// datastore value immediately
Object[] vals;
for (int i = 0; i < cols.length; i++) {
if (!cols[i].isRelationId())
continue;
if (!(handler instanceof RelationId))
break;
if (cols.length == 1) {
val = ((RelationId) handler).toRelationDataStoreValue
((OpenJPAStateManager) val, cols[i]);
} else {
vals = (Object[]) val;
vals[i] = ((RelationId) handler).toRelationDataStoreValue
((OpenJPAStateManager) vals[i], cols[i]);
}
}
return val;
}
/**
* Throw the proper exception if the given handler-controlled value
* represents an unjoinable relation.
*/
public static void assertJoinable(ValueMapping vm) {
ClassMapping rel = vm.getTypeMapping();
if (rel != null && (rel.getTable() == null
|| !rel.getTable().equals(vm.getFieldMapping().getTable())))
throw RelationStrategies.unjoinable(vm);
}
}