org.apache.openjpa.jdbc.schema.LocalConstraint 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.schema;
import java.util.ArrayList;
import java.util.List;
import org.apache.openjpa.jdbc.identifier.DBIdentifier;
import org.apache.openjpa.lib.util.Localizer;
import org.apache.openjpa.util.InvalidStateException;
/**
* Constraint over local table columns, as opposed to a foreign key which
* spans tables. Column APIs can represent a full constraint or a partial
* constraint, aligning with {@link java.sql.DatabaseMetaData}.
*
* @author Abe White
*/
@SuppressWarnings("serial")
public abstract class LocalConstraint
extends Constraint {
private static final Localizer _loc = Localizer.forPackage
(LocalConstraint.class);
private List _colList = null;
private Column[] _cols = null;
/**
* Default constructor.
*/
public LocalConstraint() {
}
/**
* Constructor.
*
* @param name the name of the constraint, if any
* @param table the table of the constraint
* @deprecated
*/
public LocalConstraint(String name, Table table) {
super(name, table);
}
public LocalConstraint(DBIdentifier name, Table table) {
super(name, table);
}
/**
* Called when the constraint is removed from its table.
*/
void remove() {
// remove all columns
for (Column c : _cols) {
c.removeConstraint(this);
}
setColumns(null);
super.remove();
}
/**
* Return all the columns the constraint spans.
*/
public Column[] getColumns() {
if (_cols == null)
_cols = (_colList == null) ? Schemas.EMPTY_COLUMNS
: (Column[]) _colList.toArray(new Column[_colList.size()]);
return _cols;
}
/**
* Set the columns the constraint spans.
*/
public void setColumns(Column[] cols) {
Column[] cur = getColumns();
for (int i = 0; i < cur.length; i++)
removeColumn(cur[i]);
if (cols != null)
for (int i = 0; i < cols.length; i++)
addColumn(cols[i]);
}
/**
* Add a column to the constraint.
*/
public void addColumn(Column col) {
if (col == null)
throw new InvalidStateException(_loc.get("table-mismatch",
col == null ? null : col.getTable(),
col == null ? null : getTable()));
if (_colList == null)
_colList = new ArrayList(3);
else if (_colList.contains(col))
return;
_colList.add(col);
_cols = null;
col.addConstraint(this);
}
/**
* Remove a column from the constraint.
*
* @return true if the column was removed, false if not part of the
* primary key
*/
public boolean removeColumn(Column col) {
if (col == null || _colList == null)
return false;
if (_colList.remove(col)) {
_cols = null;
col.removeConstraint(this);
return true;
}
return false;
}
/**
* Return true if the pk includes the given column.
*/
public boolean containsColumn(Column col) {
if (col == null || _colList == null)
return false;
return _colList.contains(col);
}
/**
* Ref all columns in this constraint.
*/
public void refColumns() {
Column[] cols = getColumns();
for (int i = 0; i < cols.length; i++)
cols[i].ref();
}
/**
* Deref all columns in this constraint.
*/
public void derefColumns() {
Column[] cols = getColumns();
for (int i = 0; i < cols.length; i++)
cols[i].deref();
}
/**
* Return true if the given columns match the columns of this constraint.
*/
public boolean columnsMatch(Column[] ocols) {
Column[] cols = getColumns();
if (cols.length != ocols.length)
return false;
for (int i = 0; i < ocols.length; i++)
if (!hasColumn(cols, ocols[i]))
return false;
return true;
}
/**
* Return whether the given column exists in the array.
*/
private static boolean hasColumn(Column[] cols, Column col) {
for (int i = 0; i < cols.length; i++)
if (cols[i].getQualifiedPath().equals(col.getQualifiedPath()))
return true;
return false;
}
/**
* Return true if the columns of this constraint matches that of
* the given one. The constraints are not compared on name.
*/
protected boolean equalsLocalConstraint(LocalConstraint lc) {
if (lc == this)
return true;
if (lc == null)
return false;
return columnsMatch(lc.getColumns());
}
}