/*******************************************************************************
* Copyright (c) 1998, 2011 Oracle. All rights reserved.
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v1.0 and Eclipse Distribution License v. 1.0
* which accompanies this distribution.
* The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html
* and the Eclipse Distribution License is available at
* http://www.eclipse.org/org/documents/edl-v10.php.
*
* Contributors:
* Oracle - initial API and implementation from Oracle TopLink
******************************************************************************/
package org.eclipse.persistence.sequencing;
import java.io.StringWriter;
import org.eclipse.persistence.queries.*;
import org.eclipse.persistence.internal.databaseaccess.DatabasePlatform;
import org.eclipse.persistence.internal.helper.DatabaseTable;
/**
* <p>
* <b>Purpose</b>: Defines sequencing through using a SEQUENCE table.
* <p>
* <b>Description</b>
* This is the default sequencing mechanism.
* A table defaulting to SEQUENCE is used to generate unique ids.
* The table has a name field (SEQ_NAME) storing each sequences name,
* and a counter (SEQ_COUNT) storing the last sequence id generated.
* There will be a row in the table for each sequence object.
*/
public class TableSequence extends QuerySequence {
/** Default sequence table name
* @deprecated
* Use an empty string as a default sequence table name instead,
* that triggers usage of platform.getDefaultSequenceTableName() when the sequence is connected.
*/
public static final String defaultTableName = "SEQUENCE";
/** Hold the database table */
protected DatabaseTable table;
/** Hold the name of the column in the sequence table which specifies the sequence numeric value */
protected String counterFieldName = "SEQ_COUNT";
/** Hold the name of the column in the sequence table which specifies the sequence name */
protected String nameFieldName = "SEQ_NAME";
public TableSequence() {
super(false, true);
setTableName("");
}
/**
* Create a new sequence with the name.
*/
public TableSequence(String name) {
super(name, false, true);
setTableName("");
}
/**
* Create a new sequence with the name and sequence pre-allocation size.
*/
public TableSequence(String name, int size) {
super(name, size, false, true);
setTableName("");
}
public TableSequence(String name, int size, int initialValue) {
super(name, size, initialValue, false, true);
setTableName("");
}
/**
* Create a new sequence with the name, and the sequence table name.
*/
public TableSequence(String name, String tableName) {
this(name);
setTableName(tableName);
}
/**
* Create a new sequence with the name, and the sequence table information.
*/
public TableSequence(String name, String tableName, String nameFieldName, String counterFieldName) {
this(name);
setTableName(tableName);
setNameFieldName(nameFieldName);
setCounterFieldName(counterFieldName);
}
public TableSequence(String name, int size, String tableName) {
this(name, size);
setTableName(tableName);
}
public TableSequence(String name, int size, String tableName, String nameFieldName, String counterFieldName) {
this(name, size);
setTableName(tableName);
setNameFieldName(nameFieldName);
setCounterFieldName(counterFieldName);
}
public boolean isTable() {
return true;
}
public boolean equals(Object obj) {
if (obj instanceof TableSequence) {
TableSequence other = (TableSequence)obj;
if (equalNameAndSize(this, other)) {
return getTableName().equals(other.getTableName()) && getCounterFieldName().equals(other.getCounterFieldName()) && getNameFieldName().equals(other.getNameFieldName());
} else {
return false;
}
} else {
return false;
}
}
public String getCounterFieldName() {
return counterFieldName;
}
public void setCounterFieldName(String name) {
counterFieldName = name;
}
public String getNameFieldName() {
return nameFieldName;
}
public void setNameFieldName(String name) {
nameFieldName = name;
}
public DatabaseTable getTable() {
return table;
}
public String getTableName() {
return getTable().getQualifiedName();
}
public String getQualifiedTableName() {
return getQualified(getTableName());
}
public void setTable(DatabaseTable table) {
this.table = table;
}
public void setTableName(String name) {
table = new DatabaseTable(name);
}
public void onConnect() {
if(this.table.getName().length() == 0) {
this.table.setName(((DatabasePlatform)getDatasourcePlatform()).getDefaultSequenceTableName());
}
super.onConnect();
}
protected ValueReadQuery buildSelectQuery() {
ValueReadQuery query = new ValueReadQuery();
query.addArgument(getNameFieldName());
StringWriter writer = new StringWriter();
writer.write("SELECT " + getCounterFieldName());
writer.write(" FROM " + getQualifiedTableName());
writer.write(" WHERE " + getNameFieldName());
writer.write(" = #" + getNameFieldName());
query.setSQLString(writer.toString());
return query;
}
protected DataModifyQuery buildUpdateQuery() {
DataModifyQuery query = new DataModifyQuery();
query.addArgument(getNameFieldName());
query.addArgument("PREALLOC_SIZE");
StringWriter writer = new StringWriter();
writer.write("UPDATE " + getQualifiedTableName());
writer.write(" SET " + getCounterFieldName());
writer.write(" = " + getCounterFieldName());
writer.write(" + #PREALLOC_SIZE");
writer.write(" WHERE " + getNameFieldName() + " = #" + getNameFieldName());
query.setSQLString(writer.toString());
return query;
}
}