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1 package org.hibernate.tuple;
3
4 import java.io.IOException  ;
5 import java.io.Serializable ;
6 import java.lang.reflect.Constructor ;
7
8 import net.sf.cglib.reflect.FastClass;
9
10 import org.apache.commons.logging.Log;
11 import org.apache.commons.logging.LogFactory;
12 import org.hibernate.InstantiationException;
13 import org.hibernate.PropertyNotFoundException;
14 import org.hibernate.mapping.PersistentClass;
15 import org.hibernate.mapping.Component;
16 import org.hibernate.util.ReflectHelper;
17
18
21 public class PojoInstantiator implements Instantiator, Serializable {
22
23 private static final Log log = LogFactory.getLog(PojoInstantiator.class);
24
25 private transient Constructor constructor;
26
27 private final Class mappedClass;
28 private final transient FastClass fastClass;
29 private final boolean embeddedIdentifier;
30 private final Class proxyInterface;
31
32 public PojoInstantiator(Component component, FastClass fastClass) {
33 this.mappedClass = component.getComponentClass();
34 this.fastClass = fastClass;
35
36 this.proxyInterface = null;
37 this.embeddedIdentifier = false;
38
39 try {
40 constructor = ReflectHelper.getDefaultConstructor(mappedClass);
41 }
42 catch ( PropertyNotFoundException pnfe ) {
43 log.info(
44 "no default (no-argument) constructor for class: " +
45 mappedClass.getName() +
46 " (class must be instantiated by Interceptor)"
47 );
48 constructor = null;
49 }
50 }
51
52 public PojoInstantiator(PersistentClass persistentClass, FastClass fastClass) {
53 this.mappedClass = persistentClass.getMappedClass();
54 this.proxyInterface = persistentClass.getProxyInterface();
55 this.embeddedIdentifier = persistentClass.hasEmbeddedIdentifier();
56 this.fastClass = fastClass;
57
58 try {
59 constructor = ReflectHelper.getDefaultConstructor(mappedClass);
60 }
61 catch ( PropertyNotFoundException pnfe ) {
62 log.info(
63 "no default (no-argument) constructor for class: " +
64 mappedClass.getName() +
65 " (class must be instantiated by Interceptor)"
66 );
67 constructor = null;
68 }
69 }
70
71 private void readObject(java.io.ObjectInputStream stream)
72 throws ClassNotFoundException , IOException {
73 stream.defaultReadObject();
74 constructor = ReflectHelper.getDefaultConstructor(mappedClass);
75 }
76
77 public Object instantiate() {
78 if ( ReflectHelper.isAbstractClass(mappedClass) ) {
79 throw new InstantiationException ( "Cannot instantiate abstract class or interface: ", mappedClass );
80 }
81 else if ( fastClass != null ) {
82 try {
83 return fastClass.newInstance();
84 }
85 catch ( Throwable t ) {
86 throw new InstantiationException ( "Could not instantiate entity with CGLIB: ", mappedClass, t );
87 }
88 }
89 else if ( constructor == null ) {
90 throw new InstantiationException ( "No default constructor for entity: ", mappedClass );
91 }
92 else {
93 try {
94 return constructor.newInstance( null );
95 }
96 catch ( Exception e ) {
97 throw new InstantiationException ( "Could not instantiate entity: ", mappedClass, e );
98 }
99 }
100 }
101
102 public Object instantiate(Serializable id) {
103 if ( embeddedIdentifier && id != null && id.getClass().equals(mappedClass) ) {
104 return id;
105 }
106 else {
107 return instantiate();
108 }
109 }
110
111 public boolean isInstance(Object object) {
112 return mappedClass.isInstance(object) ||
113 ( proxyInterface!=null && proxyInterface.isInstance(object) ); }
115 } |
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