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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
This commit is contained in:
Gail Badner 2010-03-24 19:18:08 +00:00
parent 186e9fc115
commit 3ad551a88a
16 changed files with 517 additions and 24 deletions
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14
core/src/main/java/org/hibernate/criterion/AliasedProjection.java
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@ -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;
@ -64,6 +64,12 @@ public class AliasedProjection 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 Type[] getTypes(String alias, Criteria criteria, CriteriaQuery criteriaQuery)
throws HibernateException {
return this.alias.equals(alias) ?
@ -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 };
}

14
core/src/main/java/org/hibernate/criterion/Distinct.java
View File

@ -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();
}

70
core/src/main/java/org/hibernate/criterion/EnhancedProjection.java Normal file
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@ -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);
}

2
core/src/main/java/org/hibernate/criterion/IdentifierProjection.java
View File

@ -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();
}

35
core/src/main/java/org/hibernate/criterion/ProjectionList.java
View File

@ -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);

17
core/src/main/java/org/hibernate/criterion/PropertyProjection.java
View File

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

27
core/src/main/java/org/hibernate/criterion/SimpleProjection.java
View File

@ -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);
@ -43,6 +45,10 @@ public abstract class SimpleProjection implements Projection {
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;
@ -52,6 +58,25 @@ public abstract class SimpleProjection implements Projection {
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];
}

13
core/src/main/java/org/hibernate/loader/criteria/CriteriaLoader.java
View File

@ -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++ ) {
result[i] = types[i].nullSafeGet(rs, columnAliases[i], session, null);
for ( int i=0, pos=0; i<result.length; i++ ) {
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();
}

16
core/src/main/java/org/hibernate/loader/criteria/CriteriaQueryTranslator.java
View File

@ -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 ?
null :
projection.getColumnAliases( propertyName, 0 );
String[] projectionColumns = null;
if ( projection != null ) {
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

58
testsuite/src/test/java/org/hibernate/test/criteria/CityState.java Normal file
View File

@ -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;
}
}

11
testsuite/src/test/java/org/hibernate/test/criteria/Course.java
View File

@ -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;
}
}

29
testsuite/src/test/java/org/hibernate/test/criteria/CourseMeeting.java Normal file
View File

@ -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;
}
}

47
testsuite/src/test/java/org/hibernate/test/criteria/CourseMeetingId.java Normal file
View File

@ -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;
}
}

147
testsuite/src/test/java/org/hibernate/test/criteria/CriteriaQueryTest.java
View File

@ -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();

20
testsuite/src/test/java/org/hibernate/test/criteria/Enrolment.hbm.xml
View File

@ -10,14 +10,34 @@
<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"/>

9
testsuite/src/test/java/org/hibernate/test/criteria/Student.java
View File

@ -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;
}