Java tutorial
package org.jumpmind.db.model; /* * 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. */ import java.io.Serializable; import org.apache.commons.lang.builder.EqualsBuilder; import org.apache.commons.lang.builder.HashCodeBuilder; /** * Represents a reference between a column in the local table and a column in another table. * * @version $Revision: 463305 $ */ public class Reference implements Cloneable, Serializable { /** Unique ID for serialization purposes. */ private static final long serialVersionUID = 6062467640266171664L; /** The sequence value within the key. */ private int _sequenceValue; /** The local column. */ private Column _localColumn; /** The foreign column. */ private Column _foreignColumn; /** The name of the local column. */ private String _localColumnName; /** The name of the foreign column. */ private String _foreignColumnName; /** * Creates a new, empty reference. */ public Reference() { } /** * Creates a new reference between the two given columns. * * @param localColumn The local column * @param foreignColumn The remote column */ public Reference(Column localColumn, Column foreignColumn) { setLocalColumn(localColumn); setForeignColumn(foreignColumn); } /** * Returns the sequence value within the owning key. * * @return The sequence value */ public int getSequenceValue() { return _sequenceValue; } /** * Sets the sequence value within the owning key. Please note * that you should not change the value once the reference has * been added to a key. * * @param sequenceValue The sequence value */ public void setSequenceValue(int sequenceValue) { _sequenceValue = sequenceValue; } /** * Returns the local column. * * @return The local column */ public Column getLocalColumn() { return _localColumn; } /** * Sets the local column. * * @param localColumn The local column */ public void setLocalColumn(Column localColumn) { _localColumn = localColumn; _localColumnName = (localColumn == null ? null : localColumn.getName()); } /** * Returns the foreign column. * * @return The foreign column */ public Column getForeignColumn() { return _foreignColumn; } /** * Sets the foreign column. * * @param foreignColumn The foreign column */ public void setForeignColumn(Column foreignColumn) { _foreignColumn = foreignColumn; _foreignColumnName = (foreignColumn == null ? null : foreignColumn.getName()); } /** * Returns the name of the local column. * * @return The column name */ public String getLocalColumnName() { return _localColumnName; } /** * Sets the name of the local column. Note that you should not use this method when * manipulating the model manually. Rather use the {@link #setLocalColumn(Column)} method. * * @param localColumnName The column name */ public void setLocalColumnName(String localColumnName) { if ((_localColumn != null) && !_localColumn.getName().equals(localColumnName)) { _localColumn = null; } _localColumnName = localColumnName; } /** * Returns the name of the foreign column. * * @return The column name */ public String getForeignColumnName() { return _foreignColumnName; } /** * Sets the name of the remote column. Note that you should not use this method when * manipulating the model manually. Rather use the {@link #setForeignColumn(Column)} method. * * @param foreignColumnName The column name */ public void setForeignColumnName(String foreignColumnName) { if ((_foreignColumn != null) && !_foreignColumn.getName().equals(foreignColumnName)) { _foreignColumn = null; } _foreignColumnName = foreignColumnName; } /** * {@inheritDoc} */ public Object clone() throws CloneNotSupportedException { Reference result = (Reference) super.clone(); result._localColumnName = _localColumnName; result._foreignColumnName = _foreignColumnName; return result; } /** * {@inheritDoc} */ public boolean equals(Object obj) { if (obj instanceof Reference) { Reference other = (Reference) obj; return new EqualsBuilder().append(_localColumnName, other._localColumnName) .append(_foreignColumnName, other._foreignColumnName).isEquals(); } else { return false; } } /** * Compares this reference to the given one while ignoring the case of identifiers. * * @param otherRef The other reference * @return <code>true</code> if this reference is equal (ignoring case) to the given one */ public boolean equalsIgnoreCase(Reference otherRef) { return (otherRef != null) && _localColumnName.equalsIgnoreCase(otherRef._localColumnName) && _foreignColumnName.equalsIgnoreCase(otherRef._foreignColumnName); } /** * {@inheritDoc} */ public int hashCode() { return new HashCodeBuilder(17, 37).append(_localColumnName).append(_foreignColumnName).toHashCode(); } /** * {@inheritDoc} */ public String toString() { StringBuffer result = new StringBuffer(); result.append(getLocalColumnName()); result.append(" -> "); result.append(getForeignColumnName()); return result.toString(); } }