4:49 p.m.
Author: steve.ebersole(a)jboss.com
Date: 2009-10-28 11:49:36 -0400 (Wed, 28 Oct 2009)
New Revision: 17867
Added:
core/trunk/core/src/test/java/org/hibernate/dialect/DerbyDialectTestCase.java
Modified:
core/trunk/core/src/main/java/org/hibernate/dialect/DerbyDialect.java
Log:
HHH-3972 - Adding FETCH FIRST and OFFSET support to DerbyDialect
Modified: core/trunk/core/src/main/java/org/hibernate/dialect/DerbyDialect.java
===================================================================
--- core/trunk/core/src/main/java/org/hibernate/dialect/DerbyDialect.java 2009-10-28
12:41:56 UTC (rev 17866)
+++ core/trunk/core/src/main/java/org/hibernate/dialect/DerbyDialect.java 2009-10-28
15:49:36 UTC (rev 17867)
@@ -27,6 +27,7 @@
import org.hibernate.Hibernate;
import org.hibernate.QueryException;
import org.hibernate.HibernateException;
+import org.hibernate.util.ReflectHelper;
import org.hibernate.engine.Mapping;
import org.hibernate.engine.SessionFactoryImplementor;
import org.hibernate.type.Type;
@@ -39,7 +40,11 @@
import java.util.List;
import java.util.ArrayList;
+import java.lang.reflect.Method;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
/**
* Hibernate Dialect for Cloudscape 10 - aka Derby. This implements both an
* override for the identity column generator as well as for the case statement
@@ -49,13 +54,39 @@
* @author Simon Johnston
*/
public class DerbyDialect extends DB2Dialect {
+ private static final Logger log = LoggerFactory.getLogger( DerbyDialect.class );
+ private int driverVersionMajor;
+ private int driverVersionMinor;
+
public DerbyDialect() {
super();
registerFunction( "concat", new DerbyConcatFunction() );
registerFunction( "trim", new DerbyTrimFunctionEmulation() );
+ determineDriverVersion();
}
+ /*package*/ void determineDriverVersion() {
+ try {
+ // locate the derby sysinfo class and query its version info
+ final Class sysinfoClass = ReflectHelper.classForName(
"org.apache.derby.tools.sysinfo", this.getClass() );
+ final Method majorVersionGetter = sysinfoClass.getMethod( "getMajorVersion",
ReflectHelper.NO_PARAM_SIGNATURE );
+ final Method minorVersionGetter = sysinfoClass.getMethod( "getMinorVersion",
ReflectHelper.NO_PARAM_SIGNATURE );
+ driverVersionMajor = ( (Integer) majorVersionGetter.invoke( null,
ReflectHelper.NO_PARAMS ) ).intValue();
+ driverVersionMinor = ( (Integer) minorVersionGetter.invoke( null,
ReflectHelper.NO_PARAMS ) ).intValue();
+ }
+ catch ( Exception e ) {
+ log.warn( "Unable to load/access derby driver class sysinfo to check versions :
" + e );
+ driverVersionMajor = -1;
+ driverVersionMinor = -1;
+ }
+ }
+
+ /*package*/ boolean isTenPointFiveReleaseOrNewer() {
+ return driverVersionMajor > 10 || ( driverVersionMajor == 10 &&
driverVersionMinor >= 5 );
+ }
+
+
/**
* This is different in Cloudscape to DB2.
*/
@@ -83,13 +114,77 @@
}
public boolean supportsLimit() {
- return false;
+ return isTenPointFiveReleaseOrNewer();
}
public boolean supportsLimitOffset() {
- return false;
+ return isTenPointFiveReleaseOrNewer();
}
+ /**
+ * {@inheritDoc}
+ * <p/>
+ * From Derby 10.5 Docs:
+ * <pre>
+ * Query
+ * [ORDER BY clause]
+ * [result offset clause]
+ * [fetch first clause]
+ * [FOR UPDATE clause]
+ * [WITH {RR|RS|CS|UR}]
+ * </pre>
+ */
+ public String getLimitString(String query, final int offset, final int limit) {
+ StringBuffer sb = new StringBuffer(query.length() + 50);
+
+ final String normalizedSelect = query.toLowerCase().trim();
+ final int forUpdateIndex = normalizedSelect.lastIndexOf( "for update") ;
+
+ if ( hasForUpdateClause( forUpdateIndex ) ) {
+ sb.append( query.substring( 0, forUpdateIndex-1 ) );
+ }
+ else if ( hasWithClause( normalizedSelect ) ) {
+ sb.append( query.substring( 0, getWithIndex( query ) - 1 ) );
+ }
+ else {
+ sb.append( query );
+ }
+
+ if ( offset == 0 ) {
+ sb.append( " fetch first " );
+ }
+ else {
+ sb.append( " offset " ).append( offset ).append( " rows fetch next
" );
+ }
+
+ sb.append( limit ).append( " rows only" );
+
+ if ( hasForUpdateClause( forUpdateIndex ) ) {
+ sb.append(' ');
+ sb.append( query.substring( forUpdateIndex ) );
+ }
+ else if ( hasWithClause( normalizedSelect ) ) {
+ sb.append( ' ' ).append( query.substring( getWithIndex( query ) ) );
+ }
+ return sb.toString();
+ }
+
+ private boolean hasForUpdateClause(int forUpdateIndex) {
+ return forUpdateIndex >= 0;
+ }
+
+ private boolean hasWithClause(String normalizedSelect){
+ return normalizedSelect.startsWith( "with ", normalizedSelect.length()-7 );
+ }
+
+ private int getWithIndex(String querySelect) {
+ int i = querySelect.lastIndexOf( "with " );
+ if ( i < 0 ) {
+ i = querySelect.lastIndexOf( "WITH " );
+ }
+ return i;
+ }
+
public String getQuerySequencesString() {
return null ;
}
Added: core/trunk/core/src/test/java/org/hibernate/dialect/DerbyDialectTestCase.java
===================================================================
--- core/trunk/core/src/test/java/org/hibernate/dialect/DerbyDialectTestCase.java
(rev 0)
+++
core/trunk/core/src/test/java/org/hibernate/dialect/DerbyDialectTestCase.java 2009-10-28
15:49:36 UTC (rev 17867)
@@ -0,0 +1,93 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * Copyright (c) 2009 by Red Hat Inc and/or its affiliates or by
+ * third-party contributors as indicated by either @author tags or express
+ * copyright attribution statements applied by the authors. All
+ * third-party contributions are distributed under license by Red Hat Inc.
+ *
+ * This copyrighted material is made available to anyone wishing to use, modify,
+ * copy, or redistribute it subject to the terms and conditions of the GNU
+ * Lesser General Public License, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this distribution; if not, write to:
+ * Free Software Foundation, Inc.
+ * 51 Franklin Street, Fifth Floor
+ * Boston, MA 02110-1301 USA
+ */
+package org.hibernate.dialect;
+
+import junit.framework.TestCase;
+
+/**
+ * Testing of patched support for Derby limit and ofset queries; see HHH-3972
+ *
+ * @author Evan Leonard
+ */
+public class DerbyDialectTestCase extends TestCase {
+
+ private static class LocalDerbyDialect extends DerbyDialect {
+ protected boolean isTenPointFiveReleaseOrNewer() {
+ return true; // for test sake :)
+ }
+ }
+
+ public void testInsertLimitClause() {
+ final int limit = 50;
+ final String input = "select * from tablename t where t.cat = 5";
+ final String expected = "select * from tablename t where t.cat = 5 fetch first
" + limit + " rows only";
+
+ final String actual = new LocalDerbyDialect().getLimitString( input, 0, limit );
+ assertEquals( expected, actual );
+ }
+
+ public void testInsertLimitWithOffsetClause() {
+ final int limit = 50;
+ final int offset = 200;
+ final String input = "select * from tablename t where t.cat = 5";
+ final String expected = "select * from tablename t where t.cat = 5 offset " +
offset + " rows fetch next " + limit + " rows only";
+
+ final String actual = new LocalDerbyDialect().getLimitString( input, offset, limit );
+ assertEquals( expected, actual );
+ }
+
+
+ public void testInsertLimitWithForUpdateClause() {
+ final int limit = 50;
+ final int offset = 200;
+ final String input = "select c11 as col1, c12 as col2, c13 as col13 from t1 for
update of c11, c13";
+ final String expected = "select c11 as col1, c12 as col2, c13 as col13 from t1
offset " + offset
+ + " rows fetch next " + limit + " rows only for update of c11,
c13";
+
+ final String actual = new LocalDerbyDialect().getLimitString( input, offset, limit );
+ assertEquals( expected, actual );
+ }
+
+ public void testInsertLimitWithWithClause() {
+ final int limit = 50;
+ final int offset = 200;
+ final String input = "select c11 as col1, c12 as col2, c13 as col13 from t1 where
flight_id between 'AA1111' and 'AA1112' with rr";
+ final String expected = "select c11 as col1, c12 as col2, c13 as col13 from t1
where flight_id between 'AA1111' and 'AA1112' offset " + offset
+ + " rows fetch next " + limit + " rows only with rr";
+
+ final String actual = new LocalDerbyDialect().getLimitString( input, offset, limit );
+ assertEquals( expected, actual );
+ }
+
+ public void testInsertLimitWithForUpdateAndWithClauses() {
+ final int limit = 50;
+ final int offset = 200;
+ final String input = "select c11 as col1, c12 as col2, c13 as col13 from t1 where
flight_id between 'AA1111' and 'AA1112' for update of c11,c13 with
rr";
+ final String expected = "select c11 as col1, c12 as col2, c13 as col13 from t1
where flight_id between 'AA1111' and 'AA1112' offset " + offset
+ + " rows fetch next " + limit + " rows only for update of c11,c13 with
rr";
+
+ final String actual = new LocalDerbyDialect().getLimitString( input, offset, limit );
+ assertEquals( expected, actual );
+ }
+}