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1 package org.hibernate.loader.entity;
3
4 import java.io.Serializable  ;
5 import java.sql.ResultSet ;
6 import java.sql.SQLException ;
7 import java.util.List ;
8 import java.util.Map ;
9
10 import org.apache.commons.logging.Log;
11 import org.apache.commons.logging.LogFactory;
12 import org.hibernate.HibernateException;
13 import org.hibernate.LockMode;
14 import org.hibernate.MappingException;
15 import org.hibernate.engine.SessionFactoryImplementor;
16 import org.hibernate.engine.SessionImplementor;
17 import org.hibernate.loader.JoinWalker;
18 import org.hibernate.loader.OuterJoinLoader;
19 import org.hibernate.persister.entity.OuterJoinLoadable;
20 import org.hibernate.type.Type;
21
22
30 public class EntityLoader extends OuterJoinLoader
31 implements UniqueEntityLoader {
32
33 private static final Log log = LogFactory.getLog(EntityLoader.class);
34
35 private final OuterJoinLoadable persister;
36 private final Type uniqueKeyType;
37 private final boolean batchLoader;
38 private final String entityName;
39
40 public EntityLoader(
41 OuterJoinLoadable persister,
42 LockMode lockMode,
43 SessionFactoryImplementor factory,
44 Map enabledFilters)
45 throws MappingException {
46 this(persister, 1, lockMode, factory, enabledFilters);
47 }
48
49 public EntityLoader(
50 OuterJoinLoadable persister,
51 int batchSize,
52 LockMode lockMode,
53 SessionFactoryImplementor factory,
54 Map enabledFilters)
55 throws MappingException {
56 this(
57 persister,
58 persister.getIdentifierColumnNames(),
59 persister.getIdentifierType(),
60 batchSize,
61 lockMode,
62 factory,
63 enabledFilters
64 );
65 }
66
67 public EntityLoader(
68 OuterJoinLoadable persister,
69 String [] uniqueKey,
70 Type uniqueKeyType,
71 int batchSize,
72 LockMode lockMode,
73 SessionFactoryImplementor factory,
74 Map enabledFilters)
75 throws MappingException {
76 super(factory, enabledFilters);
77
78 this.uniqueKeyType = uniqueKeyType;
79 this.entityName = persister.getEntityName();
80 this.persister = persister;
81
82 JoinWalker walker = new EntityJoinWalker(
83 persister,
84 uniqueKey,
85 batchSize,
86 lockMode,
87 factory,
88 enabledFilters
89 );
90 initFromWalker( walker );
91
92 postInstantiate();
93
94 batchLoader = batchSize > 1;
95
96 log.debug( "Static select for entity " + entityName + ": " + getSQLString() );
97
98 }
99
100 public Object load(Serializable id, Object optionalObject, SessionImplementor session)
101 throws HibernateException {
102 return load(session, id, optionalObject, id);
103 }
104
105 public Object loadByUniqueKey(SessionImplementor session, Object key)
106 throws HibernateException {
107 return load(session, key, null, null);
108 }
109
110 private Object load(
111 SessionImplementor session,
112 Object id,
113 Object optionalObject,
114 Serializable optionalId)
115 throws HibernateException {
116
117 List list = loadEntity(
118 session,
119 id,
120 uniqueKeyType,
121 optionalObject,
122 entityName,
123 optionalId,
124 persister
125 );
126
127 if ( list.size()==1 ) {
128 return list.get(0);
129 }
130 else if ( list.size()==0 ) {
131 return null;
132 }
133 else {
134 if ( getCollectionOwners()!=null ) {
135 return list.get(0);
136 }
137 else {
138 throw new HibernateException(
139 "More than one row with the given identifier was found: " +
140 id +
141 ", for class: " +
142 persister.getEntityName()
143 );
144 }
145 }
146
147 }
148
149 protected Object getResultColumnOrRow(
150 Object [] row,
151 ResultSet rs,
152 SessionImplementor session)
153 throws SQLException , HibernateException {
154 return row[row.length-1];
155 }
156
157 protected boolean isSingleRowLoader() {
158 return !batchLoader;
159 }
160
161
162 } |
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