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1
19
20 package org.apache.cayenne.reflect;
21
22 import java.beans.IntrospectionException  ;
23 import java.beans.PropertyDescriptor ;
24 import java.lang.reflect.Method ;
25
26
32 public class BeanAccessor implements Accessor {
33
34 protected String propertyName;
35 protected Method readMethod;
36 protected Method writeMethod;
37 protected Object nullValue;
38
39 public BeanAccessor(Class objectClass, String propertyName, Class propertyType) {
40 if (objectClass == null) {
41 throw new IllegalArgumentException ("Null objectClass");
42 }
43
44 if (propertyName == null) {
45 throw new IllegalArgumentException ("Null propertyName");
46 }
47
48 this.propertyName = propertyName;
49 this.nullValue = PropertyUtils.defaultNullValueForType(propertyType);
50
51 try {
52 PropertyDescriptor descriptor = new PropertyDescriptor (
53 propertyName,
54 objectClass);
55
56 this.readMethod = descriptor.getReadMethod();
57 this.writeMethod = descriptor.getWriteMethod();
58 }
59 catch (IntrospectionException e) {
60 throw new PropertyException(
61 "Invalid bean property: " + propertyName,
62 this,
63 e);
64 }
65 }
66
67 public String getName() {
68 return propertyName;
69 }
70
71
74 public Object getValue(Object object) throws PropertyException {
75 if (readMethod == null) {
76 throw new PropertyException("Property '"
77 + propertyName
78 + "' is not readable", this, object);
79 }
80
81 try {
82 return readMethod.invoke(object, null);
83 }
84 catch (Throwable th) {
85 throw new PropertyException(
86 "Error reading property: " + propertyName,
87 this,
88 object,
89 th);
90 }
91 }
92
93
96 public void setValue(Object object, Object newValue) throws PropertyException {
97
98 if (writeMethod == null) {
99 throw new PropertyException("Property '"
100 + propertyName
101 + "' is not writable", this, object);
102 }
103
104 if (newValue == null) {
106 newValue = this.nullValue;
107 }
108
109 try {
110 writeMethod.invoke(object, new Object [] {
111 newValue
112 });
113 }
114 catch (Throwable th) {
115 throw new PropertyException(
116 "Error reading property: " + propertyName,
117 this,
118 object,
119 th);
120 }
121 }
122 }
123 |
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