如果你不得不面对遗留系统老式的数据库复合主键,无法享受逻辑主键(代理主键)带来的幸福生活,那么使用CompositeUserType来处理复合主键是个不错的选择.废话少说,看看如何实现:
/** * $Revision: 1.0 $ * Created: 2008-1-11 * $Date: 2008-1-11 $ * * Author: Keven Chen */ package com.comwave.ww_oa.webui.org; import java.io.Serializable; /** * @author Keven Chen * @version $Revision 1.0 $ * */ public class UserPositionId implements Serializable { private String userId; private String posId; public UserPositionId(){} public UserPositionId(String userId, String posId) { this.userId = userId; this.posId = posId; } public String getPosId() { return posId; } public void setPosId(String posId) { this.posId = posId; } public String getUserId() { return userId; } public void setUserId(String userId) { this.userId = userId; } public int hashCode() { final int PRIME = 31; int result = 1; result = PRIME * result + ((posId == null) ? 0 : posId.hashCode()); result = PRIME * result + ((userId == null) ? 0 : userId.hashCode()); return result; } public boolean equals(Object obj) { if (this == obj) return true; if (obj == null) return false; if (getClass() != obj.getClass()) return false; final UserPositionId other = (UserPositionId) obj; if (posId == null) { if (other.posId != null) return false; } else if (!posId.equals(other.posId)) return false; if (userId == null) { if (other.userId != null) return false; } else if (!userId.equals(other.userId)) return false; return true; } }
/** * $Revision: 1.0 $ * Created: 2008-1-11 * $Date: 2008-1-11 $ * * Author: Keven Chen */ package com.comwave.ww_oa.webui.org; import java.io.Serializable; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import org.hibernate.Hibernate; import org.hibernate.HibernateException; import org.hibernate.engine.SessionImplementor; import org.hibernate.type.Type; import org.hibernate.usertype.CompositeUserType; /** * @author Keven Chen * @version $Revision 1.0 $ * */ public class UserPositionIdUserType implements CompositeUserType { public Object assemble(Serializable cached, SessionImplementor session, Object owner) throws HibernateException { return deepCopy(cached); } public Object deepCopy(Object value) throws HibernateException { UserPositionId id = (UserPositionId) value; return new UserPositionId(id.getUserId(),id.getPosId()); } public Serializable disassemble(Object value, SessionImplementor session) throws HibernateException { return (Serializable) deepCopy(value); } public boolean equals(Object x, Object y) throws HibernateException { if (x==y) return true; if (x==null || y==null) return false; return x.equals(y); } public String[] getPropertyNames() { return new String[] { "userId", "posId" }; } public Type[] getPropertyTypes() { return new Type[] { Hibernate.STRING, Hibernate.STRING }; } public Object getPropertyValue(Object component, int property) throws HibernateException { UserPositionId id = (UserPositionId) component; return property == 0 ? id.getUserId() : id.getPosId(); } public void setPropertyValue(Object component, int property, Object value) throws HibernateException { UserPositionId id = (UserPositionId) component; if (property == 0) { id.setUserId((String) value); } else { id.setPosId((String) value); } } public int hashCode(Object x) throws HibernateException { return x.hashCode(); } public boolean isMutable() { return true; } public Object nullSafeGet(ResultSet rs, String[] names, SessionImplementor session, Object owner) throws HibernateException, SQLException { String userId = (String) Hibernate.STRING.nullSafeGet(rs, names[0]); String posId = (String) Hibernate.STRING.nullSafeGet(rs, names[1]); return new UserPositionId(userId,posId); } public void nullSafeSet(PreparedStatement st, Object value, int index, SessionImplementor session) throws HibernateException, SQLException { UserPositionId id = (UserPositionId) value; String userId = (id == null) ? null : id.getUserId(); String posId = (id == null) ? null :id.getPosId(); Hibernate.STRING.nullSafeSet(st,userId, index); Hibernate.STRING.nullSafeSet(st,posId, index+1); } public Object replace(Object original, Object target, SessionImplementor session, Object owner) throws HibernateException { return deepCopy(original); //TODO: improve } public Class returnedClass() { return UserPositionId.class; } }
/** * $Revision: 1.0 $ * Created: 2008-1-10 * $Date: 2008-1-10 $ * * Author: Keven Chen */ package com.comwave.ww_oa.webui.org; import java.util.ArrayList; import java.util.List; /** * @author Keven Chen * @version $Revision 1.0 $ * */ public class UserPosition { private UserPositionId id = new UserPositionId(); private User user; private Position postion; private UserPosition director; private boolean dept_director; private boolean unit_director; private boolean top_unit_director; private List underling = new ArrayList(); public List getUnderling() { return underling; } public void setUnderling(List underling) { this.underling = underling; } public boolean isDept_director() { return dept_director; } public void setDept_director(boolean dept_director) { this.dept_director = dept_director; } public Position getPostion() { return postion; } public void setPostion(Position postion) { this.postion = postion; } public boolean isTop_unit_director() { return top_unit_director; } public void setTop_unit_director(boolean top_unit_director) { this.top_unit_director = top_unit_director; } public boolean isUnit_director() { return unit_director; } public void setUnit_director(boolean unit_director) { this.unit_director = unit_director; } public User getUser() { return user; } public void setUser(User user) { this.user = user; } public UserPosition getDirector() { return director; } public void setDirector(UserPosition director) { this.director = director; } public UserPositionId getId() { return id; } public void setId(UserPositionId id) { this.id = id; } public int hashCode() { final int PRIME = 31; int result = 1; result = PRIME * result + ((id == null) ? 0 : id.hashCode()); return result; } public boolean equals(Object obj) { if (this == obj) return true; if (obj == null) return false; if (getClass() != obj.getClass()) return false; final UserPosition other = (UserPosition) obj; if (id == null) { if (other.id != null) return false; } else if (!id.equals(other.id)) return false; return true; } }
<?xml version="1.0" encoding='UTF-8'?> <!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD//EN" "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd"> <hibernate-mapping package="com.comwave.ww_oa.webui.org"> <class name="UserPosition" table="user_positions"> <id name="id" type="com.comwave.ww_oa.webui.org.UserPositionIdUserType" unsaved-value="any"> <column name="userId"/> <column name="posId"/> </id> <property name="dept_director" type="boolean"/> <property name="unit_director" type="boolean"/> <property name="top_unit_director" type="boolean"/> <bag name="underling" inverse="true"> <key> <column name="director_user_id"/> <column name="director_pos_id"/> </key> <one-to-many class="UserPosition"/> </bag> <many-to-one name="director"> <column name="director_user_id"/> <column name="director_pos_id"/> </many-to-one> </class> </hibernate-mapping>
使用:和正常的类相同的使用方式
public UserPosition getPosition(String userId,String posId) { return getPosition(new UserPositionId(userId,posId)); } public UserPosition getPosition(UserPositionId id){ return (UserPosition) getHibernateTemplate().get(UserPosition.class,id); }