HHH-1088 : Add support for projections using composite keys and components

git-svn-id: https://svn.jboss.org/repos/hibernate/core/trunk@19110 1b8cb986-b30d-0410-93ca-fae66ebed9b2

core/src/main/java/org/hibernate/criterion/AliasedProjection.java

@@ -31,7 +31,7 @@ import org.hibernate.type.Type;
 /**
  * @author Gavin King
  */
-public class AliasedProjection implements Projection {
+public class AliasedProjection implements EnhancedProjection {
 	
 	private final Projection projection;
 	private final String alias;
@@ -64,7 +64,13 @@ public class AliasedProjection implements Projection {
 		return projection.getColumnAliases(loc);
 	}
 
-	public Type[] getTypes(String alias, Criteria criteria, CriteriaQuery criteriaQuery) 
+	public String[] getColumnAliases(int loc, Criteria criteria, CriteriaQuery criteriaQuery) {
+		return projection instanceof EnhancedProjection ?
+				( ( EnhancedProjection ) projection ).getColumnAliases( loc, criteria, criteriaQuery ) :
+				getColumnAliases( loc );
+	}
+
+	public Type[] getTypes(String alias, Criteria criteria, CriteriaQuery criteriaQuery)
 	throws HibernateException {
 		return this.alias.equals(alias) ?
 				getTypes(criteria, criteriaQuery) :
@@ -77,6 +83,12 @@ public class AliasedProjection implements Projection {
 				null;
 	}
 
+	public String[] getColumnAliases(String alias, int loc, Criteria criteria, CriteriaQuery criteriaQuery) {
+		return this.alias.equals(alias) ?
+				getColumnAliases( loc, criteria, criteriaQuery ) :
+				null;
+	}
+
 	public String[] getAliases() {
 		return new String[]{ alias };
 	}

core/src/main/java/org/hibernate/criterion/Distinct.java

@@ -31,7 +31,7 @@ import org.hibernate.type.Type;
 /**
  * @author Gavin King
  */
-public class Distinct implements Projection {
+public class Distinct implements EnhancedProjection {
 
 	private final Projection projection;
 	
@@ -63,10 +63,22 @@ public class Distinct implements Projection {
 		return projection.getColumnAliases(loc);
 	}
 
+	public String[] getColumnAliases(int loc, Criteria criteria, CriteriaQuery criteriaQuery) {
+		return projection instanceof EnhancedProjection ?
+				( ( EnhancedProjection ) projection ).getColumnAliases( loc, criteria, criteriaQuery ) :
+				getColumnAliases( loc );
+	}
+
 	public String[] getColumnAliases(String alias, int loc) {
 		return projection.getColumnAliases(alias, loc);
 	}
 
+	public String[] getColumnAliases(String alias, int loc, Criteria criteria, CriteriaQuery criteriaQuery) {
+		return projection instanceof EnhancedProjection ?
+				( ( EnhancedProjection ) projection ).getColumnAliases( alias, loc, criteria, criteriaQuery ) :
+				getColumnAliases( alias, loc );
+	}
+
 	public String[] getAliases() {
 		return projection.getAliases();
 	}

core/src/main/java/org/hibernate/criterion/EnhancedProjection.java

@@ -0,0 +1,70 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * Copyright (c) 2008, Red Hat Middleware LLC or third-party contributors as
+ * indicated by the @author tags or express copyright attribution
+ * statements applied by the authors.  All third-party contributions are
+ * distributed under license by Red Hat Middleware LLC.
+ *
+ * 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.criterion;
+
+
+import java.io.Serializable;
+
+import org.hibernate.Criteria;
+import org.hibernate.HibernateException;
+import org.hibernate.type.Type;
+
+/**
+ * An "enhanced" Projection for a {@link Criteria} query.
+ *
+ * @author Gail Badner
+ * @see Projection
+ * @see Criteria
+ */
+public interface EnhancedProjection extends Projection {
+
+	/**
+	 * Get the SQL column aliases used by this projection for the columns it writes for inclusion into the
+	 * <tt>SELECT</tt> clause ({@link #toSqlString}.  Hibernate always uses column aliases to extract data from the
+	 * JDBC {@link java.sql.ResultSet}, so it is important that these be implemented correctly in order for
+	 * Hibernate to be able to extract these val;ues correctly.
+	 *
+	 * @param position Just as in {@link #toSqlString}, represents the number of <b>columns</b> rendered
+	 * prior to this projection.
+	 * @param criteria The local criteria to which this project is attached (for resolution).
+	 * @param criteriaQuery The overall criteria query instance.
+	 * @return The columns aliases.
+	 */
+	public String[] getColumnAliases(int position, Criteria criteria, CriteriaQuery criteriaQuery);
+
+	/**
+	 * Get the SQL column aliases used by this projection for the columns it writes for inclusion into the
+	 * <tt>SELECT</tt> clause ({@link #toSqlString} <i>for a particular criteria-level alias</i>.
+	 *
+	 * @param alias The criteria-level alias
+	 * @param position Just as in {@link #toSqlString}, represents the number of <b>columns</b> rendered
+	 * prior to this projection.
+	 * @param criteria The local criteria to which this project is attached (for resolution).
+	 * @param criteriaQuery The overall criteria query instance.
+	 * @return The columns aliases pertaining to a particular criteria-level alias; expected to return null if
+	 * this projection does not understand this alias.
+	 */
+	public String[] getColumnAliases(String alias, int position, Criteria criteria, CriteriaQuery criteriaQuery);
+}

core/src/main/java/org/hibernate/criterion/IdentifierProjection.java

@@ -63,6 +63,8 @@ public class IdentifierProjection extends SimpleProjection {
 				.append(" as y")
 				.append(position + i)
 				.append('_');
+			if (i < cols.length -1)
+			   buf.append(", ");			
 		}
 		return buf.toString();
 	}

core/src/main/java/org/hibernate/criterion/ProjectionList.java

@@ -35,7 +35,7 @@ import org.hibernate.util.ArrayHelper;
 /**
  * @author Gavin King
  */
-public class ProjectionList implements Projection {
+public class ProjectionList implements EnhancedProjection {
 	
 	private List elements = new ArrayList();
 	
@@ -70,7 +70,7 @@ public class ProjectionList implements Projection {
 		for ( int i=0; i<getLength(); i++ ) {
 			Projection proj = getProjection(i);
 			buf.append( proj.toSqlString(criteria, loc, criteriaQuery) );
-			loc += proj.getColumnAliases(loc).length;
+			loc += getColumnAliases(loc, criteria, criteriaQuery, proj ).length;
 			if ( i<elements.size()-1 ) buf.append(", ");
 		}
 		return buf.toString();
@@ -100,6 +100,16 @@ public class ProjectionList implements Projection {
 		return ArrayHelper.toStringArray(result);
 	}
 
+	public String[] getColumnAliases(int loc, Criteria criteria, CriteriaQuery criteriaQuery) {
+		List result = new ArrayList( getLength() );
+		for ( int i=0; i<getLength(); i++ ) {
+			String[] colAliases = getColumnAliases( loc, criteria, criteriaQuery, getProjection( i ) );
+			ArrayHelper.addAll(result, colAliases);
+			loc+=colAliases.length;
+		}
+		return ArrayHelper.toStringArray(result);
+	}
+
 	public String[] getColumnAliases(String alias, int loc) {
 		for ( int i=0; i<getLength(); i++ ) {
 			String[] result = getProjection(i).getColumnAliases(alias, loc);
@@ -109,6 +119,27 @@ public class ProjectionList implements Projection {
 		return null;
 	}
 
+	public String[] getColumnAliases(String alias, int loc, Criteria criteria, CriteriaQuery criteriaQuery) {
+		for ( int i=0; i<getLength(); i++ ) {
+			String[] result = getColumnAliases( alias, loc, criteria, criteriaQuery, getProjection(i) );
+			if (result!=null) return result;
+			loc += getColumnAliases( loc, criteria, criteriaQuery, getProjection( i ) ).length;
+		}
+		return null;
+	}
+
+	private static String[] getColumnAliases(int loc, Criteria criteria, CriteriaQuery criteriaQuery, Projection projection) {
+		return projection instanceof EnhancedProjection ?
+				( ( EnhancedProjection ) projection ).getColumnAliases( loc, criteria, criteriaQuery ) :
+				projection.getColumnAliases( loc );
+	}
+
+	private static String[] getColumnAliases(String alias, int loc, Criteria criteria, CriteriaQuery criteriaQuery, Projection projection) {
+		return projection instanceof EnhancedProjection ?
+				( ( EnhancedProjection ) projection ).getColumnAliases( alias, loc, criteria, criteriaQuery ) :
+				projection.getColumnAliases( alias, loc );
+	}
+
 	public Type[] getTypes(String alias, Criteria criteria, CriteriaQuery criteriaQuery) {
 		for ( int i=0; i<getLength(); i++ ) {
 			Type[] result = getProjection(i).getTypes(alias, criteria, criteriaQuery);
@@ -134,7 +165,7 @@ public class ProjectionList implements Projection {
 	public int getLength() {
 		return elements.size();
 	}
-	
+
 	public String toString() {
 		return elements.toString();
 	}

core/src/main/java/org/hibernate/criterion/PropertyProjection.java

@@ -61,12 +61,17 @@ public class PropertyProjection extends SimpleProjection {
 
 	public String toSqlString(Criteria criteria, int position, CriteriaQuery criteriaQuery) 
 	throws HibernateException {
-		return new StringBuffer()
+		StringBuffer buf = new StringBuffer();
-			.append( criteriaQuery.getColumn(criteria, propertyName) )
+		String[] cols = criteriaQuery.getColumnsUsingProjection( criteria, propertyName );
-			.append(" as y")
+		for ( int i=0; i<cols.length; i++ ) {
-			.append(position)
+			buf.append( cols[i] )
-			.append('_')
+				.append(" as y")
-			.toString();
+				.append(position + i)
+				.append('_');
+			if (i < cols.length -1)
+			   buf.append(", ");
+		}
+		return buf.toString();
 	}
 
 	public boolean isGrouped() {

core/src/main/java/org/hibernate/criterion/SimpleProjection.java

@@ -24,6 +24,8 @@
  */
 package org.hibernate.criterion;
 
+import java.util.Iterator;
+
 import org.hibernate.Criteria;
 import org.hibernate.HibernateException;
 import org.hibernate.type.Type;
@@ -33,7 +35,7 @@ import org.hibernate.type.Type;
  * A single-column projection that may be aliased
  * @author Gavin King
  */
-public abstract class SimpleProjection implements Projection {
+public abstract class SimpleProjection implements EnhancedProjection {
 
 	public Projection as(String alias) {
 		return Projections.alias(this, alias);
@@ -42,7 +44,11 @@ public abstract class SimpleProjection implements Projection {
 	public String[] getColumnAliases(String alias, int loc) {
 		return null;
 	}
-	
+
+	public String[] getColumnAliases(String alias, int loc, Criteria criteria, CriteriaQuery criteriaQuery) {
+		return getColumnAliases( alias, loc );
+	}
+
 	public Type[] getTypes(String alias, Criteria criteria, CriteriaQuery criteriaQuery) 
 	throws HibernateException {
 		return null;
@@ -51,7 +57,26 @@ public abstract class SimpleProjection implements Projection {
 	public String[] getColumnAliases(int loc) {
 		return new String[] { "y" + loc + "_" };
 	}
-	
+
+	public int getColumnCount(Criteria criteria, CriteriaQuery criteriaQuery) {
+		Type types[] = getTypes( criteria, criteriaQuery );
+		int count = 0;
+		for ( int i=0; i<types.length; i++ ) {
+			count += types[ i ].getColumnSpan( criteriaQuery.getFactory() );
+		}
+		return count;
+	}
+
+	public String[] getColumnAliases(int loc, Criteria criteria, CriteriaQuery criteriaQuery) {
+		int numColumns =  getColumnCount( criteria, criteriaQuery );
+		String[] aliases = new String[ numColumns ];
+		for (int i = 0; i < numColumns; i++) {
+			aliases[i] = "y" + loc + "_";
+			loc++;
+		}
+		return aliases;
+	}
+
 	public String[] getAliases() {
 		return new String[1];
 	}

core/src/main/java/org/hibernate/loader/criteria/CriteriaLoader.java

@@ -48,6 +48,7 @@ import org.hibernate.persister.entity.OuterJoinLoadable;
 import org.hibernate.persister.entity.Lockable;
 import org.hibernate.transform.ResultTransformer;
 import org.hibernate.type.Type;
+import org.hibernate.util.ArrayHelper;
 
 /**
  * A <tt>Loader</tt> for <tt>Criteria</tt> queries. Note that criteria queries are
@@ -127,8 +128,16 @@ public class CriteriaLoader extends OuterJoinLoader {
 			Type[] types = translator.getProjectedTypes();
 			result = new Object[types.length];
 			String[] columnAliases = translator.getProjectedColumnAliases();
-			for ( int i=0; i<result.length; i++ ) {
+			for ( int i=0, pos=0; i<result.length; i++ ) {
-				result[i] = types[i].nullSafeGet(rs, columnAliases[i], session, null);
+				int numColumns = types[i].getColumnSpan( session.getFactory() );
+				if ( numColumns > 1 ) {
+			    	String[] typeColumnAliases = ArrayHelper.slice( columnAliases, pos, numColumns );
+					result[i] = types[i].nullSafeGet(rs, typeColumnAliases, session, null);
+				}
+				else {
+					result[i] = types[i].nullSafeGet(rs, columnAliases[pos], session, null);
+				}
+				pos += numColumns;
 			}
 			aliases = translator.getProjectedAliases();
 		}

core/src/main/java/org/hibernate/loader/criteria/CriteriaQueryTranslator.java

@@ -42,6 +42,7 @@ import org.hibernate.LockMode;
 import org.hibernate.MappingException;
 import org.hibernate.QueryException;
 import org.hibernate.LockOptions;
+import org.hibernate.criterion.EnhancedProjection;
 import org.hibernate.hql.ast.util.SessionFactoryHelper;
 import org.hibernate.criterion.CriteriaQuery;
 import org.hibernate.criterion.Criterion;
@@ -362,7 +363,9 @@ public class CriteriaQueryTranslator implements CriteriaQuery {
 	}
 
 	public String[] getProjectedColumnAliases() {
-		return rootCriteria.getProjection().getColumnAliases( 0 );
+		return rootCriteria.getProjection() instanceof EnhancedProjection ?
+				( ( EnhancedProjection ) rootCriteria.getProjection() ).getColumnAliases( 0, rootCriteria, this ) :
+				rootCriteria.getProjection().getColumnAliases( 0 );
 	}
 
 	public String[] getProjectedAliases() {
@@ -426,10 +429,13 @@ public class CriteriaQueryTranslator implements CriteriaQuery {
 
 		//first look for a reference to a projection alias
 		final Projection projection = rootCriteria.getProjection();
-		String[] projectionColumns = projection == null ?
+		String[] projectionColumns = null;
-		                             null :
+		if ( projection != null ) {
-		                             projection.getColumnAliases( propertyName, 0 );
+			projectionColumns = ( projection instanceof EnhancedProjection ?
-
+					( ( EnhancedProjection ) projection ).getColumnAliases( propertyName, 0, rootCriteria, this ) :
+					projection.getColumnAliases( propertyName, 0 )
+			);
+		}
 		if ( projectionColumns == null ) {
 			//it does not refer to an alias of a projection,
 			//look for a property

testsuite/src/test/java/org/hibernate/test/criteria/CityState.java

@@ -0,0 +1,58 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * Copyright (c) 2010, Red Hat Middleware LLC or third-party contributors as
+ * indicated by the @author tags or express copyright attribution
+ * statements applied by the authors.  All third-party contributions are
+ * distributed under license by Red Hat Middleware LLC.
+ *
+ * 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.test.criteria;
+
+/**
+ * @author Gail Badner
+ */
+
+public class CityState {
+	private String city;
+	private String state;
+
+	public CityState() {}
+
+	public CityState(String city, String state) {
+		this.city = city;
+		this.state = state;
+	}
+
+	public String getCity() {
+		return city;
+	}
+
+	public void setCity(String city) {
+		this.city = city;
+	}
+
+	public String getState() {
+		return state;
+	}
+
+	public void setState(String state) {
+		this.state = state;
+	}
+
+}

testsuite/src/test/java/org/hibernate/test/criteria/Course.java

@@ -1,12 +1,17 @@
 //$Id: Course.java 5686 2005-02-12 07:27:32Z steveebersole $
 package org.hibernate.test.criteria;
 
+import java.util.HashSet;
+import java.util.Set;
+
 /**
  * @author Gavin King
  */
 public class Course {
 	private String courseCode;
 	private String description;
+	private Set courseMeetings = new HashSet();
+
 	public String getCourseCode() {
 		return courseCode;
 	}
@@ -19,4 +24,10 @@ public class Course {
 	public void setDescription(String description) {
 		this.description = description;
 	}
+	public Set getCourseMeetings() {
+		return courseMeetings;
+	}
+	public void setCourseMeetings(Set courseMeetings) {
+		this.courseMeetings = courseMeetings;
+	}
 }

testsuite/src/test/java/org/hibernate/test/criteria/CourseMeeting.java

@@ -0,0 +1,29 @@
+package org.hibernate.test.criteria;
+
+/**
+ * @author Gail Badner
+ */
+public class CourseMeeting {
+	private CourseMeetingId id;
+	private Course course;
+
+	public CourseMeeting() {}
+
+	public CourseMeeting(Course course, String day, int period, String location) {
+		this.id = new CourseMeetingId( course, day, period, location );
+		this.course = course;
+	}
+
+	public CourseMeetingId getId() {
+		return id;
+	}
+	public void setId(CourseMeetingId id) {
+		this.id = id;
+	}
+	public  Course getCourse() {
+		return course;
+	}
+	public void setCourse(Course course) {
+		this.course = course;
+	}
+}

testsuite/src/test/java/org/hibernate/test/criteria/CourseMeetingId.java

@@ -0,0 +1,47 @@
+package org.hibernate.test.criteria;
+
+import java.io.Serializable;
+
+/**
+ * @author Gail Badner
+ */
+public class CourseMeetingId implements Serializable {
+	private String courseCode;
+	private String day;
+	private int period;
+	private String location;
+
+	public CourseMeetingId() {}
+
+	public CourseMeetingId(Course course, String day, int period, String location) {
+		this.courseCode = course.getCourseCode();
+		this.day = day;
+		this.period = period;
+		this.location = location;
+	}
+
+	public String getCourseCode() {
+		return courseCode;
+	}
+	public void setCourseCode(String courseCode) {
+		this.courseCode = courseCode;
+	}
+	public String getDay() {
+		return day;
+	}
+	public void setDay(String day) {
+		this.day = day;
+	}
+	public int getPeriod() {
+		return period;
+	}
+	public void setPeriod(int period) {
+		this.period = period;
+	}
+	public String getLocation() {
+		return location;
+	}
+	public void setLocation(String location) {
+		this.location = location;
+	}
+}

testsuite/src/test/java/org/hibernate/test/criteria/CriteriaQueryTest.java

@@ -19,6 +19,7 @@ import org.hibernate.criterion.Example;
 import org.hibernate.criterion.MatchMode;
 import org.hibernate.criterion.Order;
 import org.hibernate.criterion.Projection;
+import org.hibernate.criterion.ProjectionList;
 import org.hibernate.criterion.Projections;
 import org.hibernate.criterion.Property;
 import org.hibernate.criterion.Restrictions;
@@ -742,6 +743,152 @@ public class CriteriaQueryTest extends FunctionalTestCase {
 		s.close();
 	}
 
+	public void testProjectedEmbeddedCompositeId() {
+		Session s = openSession();
+		Transaction t = s.beginTransaction();
+
+		Course course = new Course();
+		course.setCourseCode("HIB");
+		course.setDescription("Hibernate Training");
+		s.save(course);
+
+		Student gavin = new Student();
+		gavin.setName("Gavin King");
+		gavin.setStudentNumber(667);
+		s.save(gavin);
+
+		Student xam = new Student();
+		xam.setName("Max Rydahl Andersen");
+		xam.setStudentNumber(101);
+		s.save(xam);
+
+		Enrolment enrolment = new Enrolment();
+		enrolment.setCourse(course);
+		enrolment.setCourseCode(course.getCourseCode());
+		enrolment.setSemester((short) 1);
+		enrolment.setYear((short) 1999);
+		enrolment.setStudent(xam);
+		enrolment.setStudentNumber(xam.getStudentNumber());
+		xam.getEnrolments().add(enrolment);
+		s.save(enrolment);
+
+		enrolment = new Enrolment();
+		enrolment.setCourse(course);
+		enrolment.setCourseCode(course.getCourseCode());
+		enrolment.setSemester((short) 3);
+		enrolment.setYear((short) 1998);
+		enrolment.setStudent(gavin);
+		enrolment.setStudentNumber(gavin.getStudentNumber());
+		gavin.getEnrolments().add(enrolment);
+		s.save(enrolment);
+
+		s.flush();
+
+		List enrolments = ( List ) s.createCriteria( Enrolment.class).setProjection( Projections.id() ).list();
+		t.rollback();
+		s.close();
+	}
+
+	public void testProjectedCompositeId() {
+		Session s = openSession();
+		Transaction t = s.beginTransaction();
+
+		Course course = new Course();
+		course.setCourseCode("HIB");
+		course.setDescription("Hibernate Training");
+		course.getCourseMeetings().add( new CourseMeeting( course, "Monday", 1, "1313 Mockingbird Lane" ) );
+		s.save(course);
+		s.flush();
+
+		List data = ( List ) s.createCriteria( CourseMeeting.class).setProjection( Projections.id() ).list();
+		t.rollback();
+		s.close();
+	}
+
+	public void testProjectedComponent() {
+		Session s = openSession();
+		Transaction t = s.beginTransaction();
+
+		Student gaith = new Student();
+		gaith.setName("Gaith Bell");
+		gaith.setStudentNumber(123);
+		gaith.setCityState( new CityState( "Chicago", "Illinois" ) );
+		s.save( gaith );
+		s.flush();
+
+		List cityStates = ( List ) s.createCriteria( Student.class).setProjection( Projections.property( "cityState" )).list();
+		t.rollback();
+		s.close();
+	}
+
+	public void testProjectedListIncludesComponent() {
+		Session s = openSession();
+		Transaction t = s.beginTransaction();
+
+		Student gaith = new Student();
+		gaith.setName("Gaith Bell");
+		gaith.setStudentNumber(123);
+		gaith.setCityState( new CityState( "Chicago", "Illinois" ) );
+		s.save(gaith);
+		s.flush();
+		List data = ( List ) s.createCriteria( Student.class)
+				.setProjection( Projections.projectionList()
+					.add( Projections.property( "cityState" ) )
+					.add( Projections.property("name") ) )
+				.list();
+		t.rollback();
+		s.close();
+	}
+
+	public void testProjectedListIncludesEmbeddedCompositeId() {
+		Session s = openSession();
+		Transaction t = s.beginTransaction();
+
+		Course course = new Course();
+		course.setCourseCode("HIB");
+		course.setDescription("Hibernate Training");
+		s.save(course);
+
+		Student gavin = new Student();
+		gavin.setName("Gavin King");
+		gavin.setStudentNumber(667);
+		s.save(gavin);
+
+		Student xam = new Student();
+		xam.setName("Max Rydahl Andersen");
+		xam.setStudentNumber(101);
+		s.save(xam);
+
+		Enrolment enrolment = new Enrolment();
+		enrolment.setCourse(course);
+		enrolment.setCourseCode(course.getCourseCode());
+		enrolment.setSemester((short) 1);
+		enrolment.setYear((short) 1999);
+		enrolment.setStudent(xam);
+		enrolment.setStudentNumber(xam.getStudentNumber());
+		xam.getEnrolments().add(enrolment);
+		s.save(enrolment);
+
+		enrolment = new Enrolment();
+		enrolment.setCourse(course);
+		enrolment.setCourseCode(course.getCourseCode());
+		enrolment.setSemester((short) 3);
+		enrolment.setYear((short) 1998);
+		enrolment.setStudent(gavin);
+		enrolment.setStudentNumber(gavin.getStudentNumber());
+		gavin.getEnrolments().add(enrolment);
+		s.save(enrolment);
+		s.flush();
+		List data = ( List ) s.createCriteria( Enrolment.class)
+				.setProjection( Projections.projectionList()
+					.add( Projections.property( "semester" ) )
+					.add( Projections.property("year") )
+					.add( Projections.id() ) )
+				.list();
+		t.rollback();
+		s.close();
+	}
+
 	public void testSubcriteriaJoinTypes() {
 		Session session = openSession();
 		Transaction t = session.beginTransaction();

testsuite/src/test/java/org/hibernate/test/criteria/Enrolment.hbm.xml

@@ -10,21 +10,41 @@
 			<generator class="assigned"/>
 		</id>
 		<property name="description"/>
+        <set name="courseMeetings" inverse="true" cascade="all-delete-orphan">
+            <key column="courseCode"/>
+            <one-to-many class="CourseMeeting"/>
+        </set>
 	</class>
-	
+
+    <class name="CourseMeeting">
+        <composite-id name="id" class="CourseMeetingId">
+            <key-property name="courseCode"/>
+            <key-property name="day"/>
+            <key-property name="period"/>
+            <key-property name="location"/>
+        </composite-id>
+        <many-to-one name="course" insert="false" update="false">
+            <column name="courseCode"/>
+        </many-to-one>
+    </class>
+
 	<class name="Student">
 		<id name="studentNumber">
 		    <column name="studentId"/>
 			<generator class="assigned"/>
 		</id>
 		<property name="name" not-null="true"/>
+        <component name="cityState">
+		    <property name="city" column="address_city"/>
+            <property name="state" column="address_state"/>
+        </component>
 		<set name="enrolments" inverse="true" cascade="delete">
 			<key column="studentId"/>
 			<one-to-many class="Enrolment"/>
 		</set>
         <many-to-one name="preferredCourse" column="preferredCourseCode"/>
 	</class>
-	
+
 	<class name="Enrolment">
 		<composite-id>
 			<key-property name="studentNumber">

testsuite/src/test/java/org/hibernate/test/criteria/Student.java

@@ -10,6 +10,7 @@ import java.util.Set;
 public class Student {
 	private long studentNumber;
 	private String name;
+	private CityState cityState;
 	private Course preferredCourse;
 	private Set enrolments = new HashSet();
 
@@ -29,6 +30,14 @@ public class Student {
 		this.studentNumber = studentNumber;
 	}
 
+	public CityState getCityState() {
+		return cityState;
+	}
+
+	public void setCityState(CityState cityState) {
+		this.cityState = cityState;
+	}
+
 	public Course getPreferredCourse() {
 		return preferredCourse;
 	}