oracle.toplink.essentials.tools.schemaframework.OracleSequenceDefinition Maven / Gradle / Ivy
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* The contents of this file are subject to the terms
* of the Common Development and Distribution License
* (the "License"). You may not use this file except
* in compliance with the License.
*
* You can obtain a copy of the license at
* glassfish/bootstrap/legal/CDDLv1.0.txt or
* https://glassfish.dev.java.net/public/CDDLv1.0.html.
* See the License for the specific language governing
* permissions and limitations under the License.
*
* When distributing Covered Code, include this CDDL
* HEADER in each file and include the License file at
* glassfish/bootstrap/legal/CDDLv1.0.txt. If applicable,
* add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your
* own identifying information: Portions Copyright [yyyy]
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// Copyright (c) 1998, 2007, Oracle. All rights reserved.
package oracle.toplink.essentials.tools.schemaframework;
import java.io.*;
import oracle.toplink.essentials.exceptions.*;
import oracle.toplink.essentials.sequencing.NativeSequence;
import oracle.toplink.essentials.internal.sessions.AbstractSession;
/**
*
* Purpose: Support Oracle native sequence creation.
* Oracle has custom support for sequences.
*
*/
public class OracleSequenceDefinition extends SequenceDefinition {
/** The increment can be used to support pre-allocation. */
protected int increment;
/** The start is the first sequence value that will be available for TopLink to use. */
protected int start = 1;
public OracleSequenceDefinition(String name, int preallocationSize) {
super(name);
setIncrement(preallocationSize);
}
public OracleSequenceDefinition(String name, int preallocationSize, int start) {
super(name);
// sequence value should be positive
if(start <= 0) {
start = 1;
}
setIncrement(preallocationSize);
setStart(start);
}
public OracleSequenceDefinition(String name) {
this(name, 1);
}
public OracleSequenceDefinition(NativeSequence sequence) {
this(sequence.getName(), sequence.getPreallocationSize(), sequence.getInitialValue());
}
/**
* INTERNAL:
* Return the SQL required to create the Oracle sequence object.
*/
public Writer buildCreationWriter(AbstractSession session, Writer writer) {
try {
writer.write("CREATE SEQUENCE ");
writer.write(getFullName());
if (getIncrement() != 1) {
writer.write(" INCREMENT BY " + getIncrement());
}
// startWith value calculated using the initial value and increment.
// The first time TopLink calls select nextval, the value equal to startWith is returned.
// The first sequence value TopLink may assign is startWith - getIncrement() + 1.
int startWith = getStart() + getIncrement() - 1;
writer.write(" START WITH " + startWith);
} catch (IOException ioException) {
throw ValidationException.fileError(ioException);
}
return writer;
}
/**
* INTERNAL:
* Return the SQL required to drop the Oracle sequence object.
*/
public Writer buildDeletionWriter(AbstractSession session, Writer writer) {
try {
writer.write("DROP SEQUENCE ");
writer.write(getFullName());
} catch (IOException ioException) {
throw ValidationException.fileError(ioException);
}
return writer;
}
/**
* INTERNAL:
* Return the SQL required to alter INCREMENT BY
*/
public Writer buildAlterIncrementWriter(AbstractSession session, Writer writer) {
try {
writer.write("ALTER SEQUENCE ");
writer.write(getFullName());
writer.write(" INCREMENT BY " + getIncrement());
} catch (IOException ioException) {
throw ValidationException.fileError(ioException);
}
return writer;
}
/**
* INTERNAL:
* Check if the sequence object already exists, in which case dont create it.
*/
public boolean checkIfExist(AbstractSession session) throws DatabaseException {
try {
session.executeSelectingCall(new oracle.toplink.essentials.queryframework.SQLCall("SELECT " + getName() + ".NEXTVAL FROM DUAL"));
} catch (DatabaseException exception) {
return false;
}
return true;
}
/**
* The increment can be used to support pre-allocation.
*/
public int getIncrement() {
return increment;
}
/**
* The increment can be used to support pre-allocation.
*/
public void setIncrement(int increment) {
this.increment = increment;
}
/**
* The start used as a starting value for sequence
*/
public int getStart() {
return start;
}
/**
* The start used as a starting value for sequence
*/
public void setStart(int start) {
this.start = start;
}
/**
* The start used as a starting value for sequence
*/
public void setStartAndIncrement(int value) {
setStart(1);
setIncrement(value);
}
/**
* INTERNAL:
* Indicates whether alterIncrement is supported
*/
public boolean isAlterSupported() {
return true;
}
/**
* INTERNAL:
* Execute the SQL required to alter sequence increment.
* Assume that the sequence exists.
*/
public void alterOnDatabase(AbstractSession session) throws TopLinkException {
try {
session.executeNonSelectingCall(new oracle.toplink.essentials.queryframework.SQLCall(buildAlterIncrementWriter(session, new StringWriter()).toString()));
} catch (DatabaseException exception) {
createOnDatabase(session);
}
}
/**
* INTERNAL:
* Execute the SQL required to alter sequence increment.
* Assume that the sequence exists.
*/
public void alterIncrement(AbstractSession session, Writer schemaWriter) throws ValidationException {
if (schemaWriter == null) {
this.alterOnDatabase(session);
} else {
this.buildAlterIncrementWriter(session, schemaWriter);
}
}
}