/**
* Copyright (c) 2009-2014, Data Geekery GmbH (http://www.datageekery.com)
* All rights reserved.
*
* This work is dual-licensed
* - under the Apache Software License 2.0 (the "ASL")
* - under the jOOQ License and Maintenance Agreement (the "jOOQ License")
* =============================================================================
* You may choose which license applies to you:
*
* - If you're using this work with Open Source databases, you may choose
* either ASL or jOOQ License.
* - If you're using this work with at least one commercial database, you must
* choose jOOQ License
*
* For more information, please visit http://www.jooq.org/licenses
*
* Apache Software License 2.0:
* -----------------------------------------------------------------------------
* 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.
*
* jOOQ License and Maintenance Agreement:
* -----------------------------------------------------------------------------
* Data Geekery grants the Customer the non-exclusive, timely limited and
* non-transferable license to install and use the Software under the terms of
* the jOOQ License and Maintenance Agreement.
*
* This library is distributed with a LIMITED WARRANTY. See the jOOQ License
* and Maintenance Agreement for more details: http://www.jooq.org/licensing
*/
package org.jooq.impl;
import static org.jooq.impl.DSL.row;
import static org.jooq.impl.Utils.filterOne;
import static org.jooq.impl.Utils.first;
import static org.jooq.impl.Utils.list;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import org.jooq.AttachableInternal;
import org.jooq.DSLContext;
import org.jooq.Field;
import org.jooq.ForeignKey;
import org.jooq.Record;
import org.jooq.Result;
import org.jooq.RowN;
import org.jooq.Table;
import org.jooq.TableField;
import org.jooq.UniqueKey;
import org.jooq.exception.DetachedException;
/**
* @author Lukas Eder
*/
class ReferenceImpl<R extends Record, O extends Record> extends AbstractKey<R> implements ForeignKey<R, O> {
/**
* Generated UID
*/
private static final long serialVersionUID = 3636724364192618701L;
private final UniqueKey<O> key;
ReferenceImpl(UniqueKey<O> key, Table<R> table, TableField<R, ?>... fields) {
super(table, fields);
this.key = key;
}
@Override
public final UniqueKey<O> getKey() {
return key;
}
@SuppressWarnings("unchecked")
@Override
public final O fetchParent(R record) {
return filterOne(fetchParents(record));
}
@Override
public final Result<O> fetchParents(R... records) {
return fetchParents(list(records));
}
@SuppressWarnings("unchecked")
@Override
public final Result<R> fetchChildren(O record) {
return fetchChildren(list(record));
}
@Override
public final Result<R> fetchChildren(O... records) {
return fetchChildren(list(records));
}
@Override
public final Result<O> fetchParents(Collection<? extends R> records) {
if (records == null || records.size() == 0) {
return new ResultImpl<O>(new DefaultConfiguration(), key.getFields());
}
else {
return fetch(records, key.getTable(), key.getFieldsArray(), getFieldsArray());
}
}
@Override
public final Result<R> fetchChildren(Collection<? extends O> records) {
if (records == null || records.size() == 0) {
return new ResultImpl<R>(new DefaultConfiguration(), getFields());
}
else {
return fetch(records, getTable(), getFieldsArray(), key.getFieldsArray());
}
}
/**
* Do the actual fetching
*/
@SuppressWarnings("unchecked")
private static <R1 extends Record, R2 extends Record> Result<R1> fetch(
Collection<? extends R2> records,
Table<R1> table,
TableField<R1, ?>[] fields1,
TableField<R2, ?>[] fields2) {
// Use regular predicates
if (fields1.length == 1) {
return extractDSLContext(records)
.selectFrom(table)
.where(((Field<Object>) fields1[0]).in(extractValues(records, fields2[0])))
.fetch();
}
// Use row value expressions
else {
return extractDSLContext(records)
.selectFrom(table)
.where(row(fields1).in(extractRows(records, fields2)))
.fetch();
}
}
/**
* Extract a list of values from a set of records given some fields
*/
private static <R extends Record> List<Object> extractValues(Collection<? extends R> records, TableField<R, ?> field2) {
List<Object> result = new ArrayList<Object>();
for (R record : records) {
result.add(record.getValue(field2));
}
return result;
}
/**
* Extract a list of row value expressions from a set of records given some fields
*/
private static <R extends Record> List<RowN> extractRows(Collection<? extends R> records, TableField<R, ?>[] fields) {
List<RowN> rows = new ArrayList<RowN>();
for (R record : records) {
Object[] values = new Object[fields.length];
for (int i = 0; i < fields.length; i++) {
values[i] = record.getValue(fields[i]);
}
rows.add(row(values));
}
return rows;
}
/**
* Extract a configuration from the first record of a collection of records
*/
private static <R extends Record> DSLContext extractDSLContext(Collection<? extends R> records)
throws DetachedException {
R first = first(records);
if (first instanceof AttachableInternal) {
return DSL.using(((AttachableInternal) first).configuration());
}
else {
throw new DetachedException("Supply at least one attachable record");
}
}
// -------------------------------------------------------------------------
// XXX: Object API
// -------------------------------------------------------------------------
@Override
public String toString() {
StringBuilder sb = new StringBuilder();
sb.append("FOREIGN KEY (");
String s1 = "";
for (Field<?> field : getFields()) {
sb.append(s1);
sb.append(field);
s1 = ", ";
}
sb.append(") REFERENCES ");
sb.append(key.getTable());
sb.append("(");
String s2 = "";
for (Field<?> field : getFields()) {
sb.append(s2);
sb.append(field);
s2 = ", ";
}
sb.append(")");
return sb.toString();
}
}