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1
4 package com.tc.config.schema.repository;
5
6 import org.apache.commons.lang.ClassUtils;
7 import org.apache.xmlbeans.SchemaType;
8 import org.apache.xmlbeans.XmlException;
9 import org.apache.xmlbeans.XmlObject;
10 import org.apache.xmlbeans.XmlOptions;
11
12 import com.tc.config.schema.listen.ConfigurationChangeListener;
13 import com.tc.config.schema.listen.ConfigurationChangeListenerSet;
14 import com.tc.config.schema.validate.ConfigurationValidator;
15 import com.tc.util.Assert;
16
17 import java.lang.reflect.Field  ;
18 import java.lang.reflect.Modifier ;
19 import java.util.ArrayList ;
20 import java.util.HashSet ;
21 import java.util.Iterator ;
22 import java.util.List ;
23 import java.util.Set ;
24
25
28 public class StandardBeanRepository implements MutableBeanRepository {
29
30 private final Class requiredClass;
31 private final ConfigurationChangeListenerSet listenerSet;
32 private final Set validators;
33 private XmlObject bean;
34
35 private XmlObject preMutateCopy;
36
37 public StandardBeanRepository(Class requiredClass) {
38 Assert.assertNotNull(requiredClass);
39
40 this.requiredClass = requiredClass;
41 this.listenerSet = new ConfigurationChangeListenerSet();
42 this.validators = new HashSet ();
43 this.bean = null;
44 }
45
46 public void ensureBeanIsOfClass(Class theClass) {
47 if (!theClass.isAssignableFrom(this.requiredClass)) {
48 throw Assert.failure("You're making sure this repository requires at least " + theClass + ", but it requires "
50 + this.requiredClass + ", which isn't that class or a subclass thereof.");
51 }
52 }
53
54 public void saveCopyOfBeanInAnticipationOfFutureMutation() {
55 Assert.eval(this.preMutateCopy == null);
56 this.preMutateCopy = this.bean.copy();
57 }
58
59 public void didMutateBean() {
60 Assert.eval(this.preMutateCopy != null);
61 this.listenerSet.configurationChanged(this.preMutateCopy, this.bean);
62 this.preMutateCopy = null;
63 }
64
65 public synchronized XmlObject bean() {
66 return this.bean;
67 }
68
69 static SchemaType getTypeFieldFrom(Class theClass) {
70 try {
71 Field typeField = theClass.getField("type");
72
73 Assert.eval(typeField.getType().equals(SchemaType.class));
74
75 int modifiers = typeField.getModifiers();
76 Assert.eval(Modifier.isPublic(modifiers));
77 Assert.eval(Modifier.isStatic(modifiers));
78 Assert.eval(Modifier.isFinal(modifiers));
79
80 return (SchemaType) typeField.get(null);
81 } catch (NoSuchFieldException nsfe) {
82 throw Assert.failure("Class " + theClass.getName()
83 + ", doesn't have a 'public static final SchemaType type' field?", nsfe);
84 } catch (IllegalArgumentException iae) {
85 throw Assert.failure("Unable to get 'public static final SchemaType type' from class " + theClass.getName(), iae);
86 } catch (IllegalAccessException iae) {
87 throw Assert.failure("Unable to get 'public static final SchemaType type' from class " + theClass.getName(), iae);
88 }
89 }
90
91 public SchemaType rootBeanSchemaType() {
92 return getTypeFieldFrom(this.requiredClass);
93 }
94
95 public synchronized void setBean(XmlObject bean, String sourceDescription) throws XmlException {
96 Assert.assertNotBlank(sourceDescription);
97 Assert.eval(bean == null || this.requiredClass.isInstance(bean));
98
99 if (this.bean == bean) return;
100
101 if (bean != null) {
102 throwExceptionIfSchemaValidationFails(bean, sourceDescription);
103
104 Iterator iter = this.validators.iterator();
105 while (iter.hasNext()) {
106 ((ConfigurationValidator) iter.next()).validate(bean);
107 }
108 }
109
110 XmlObject oldBean = this.bean;
111 this.bean = bean;
112 this.listenerSet.configurationChanged(oldBean, bean);
113 }
114
115 private void throwExceptionIfSchemaValidationFails(XmlObject theBean, String sourceDescription) throws XmlException {
116 List errors = new ArrayList ();
117 XmlOptions options = new XmlOptions();
118 options = options.setLoadLineNumbers();
119 options = options.setErrorListener(errors);
120 options = options.setDocumentSourceName(sourceDescription);
121
122 boolean validated = theBean.validate(options);
123
124 if (errors.size() > 0 || (!validated)) {
125 StringBuffer descrip = new StringBuffer ();
126
127 descrip.append("The configuration from '" + sourceDescription + "' is invalid; it has " + errors.size()
128 + " error" + (errors.size() == 1 ? "" : "s") + ":\n");
129
130 int pos = 1;
131 Iterator iter = errors.iterator();
132 while (iter.hasNext()) {
133 descrip.append(" " + pos + ": " + iter.next().toString() + "\n");
134 pos++;
135 }
136
137 throw new XmlException(descrip.toString());
138 }
139 }
140
141 public void addListener(ConfigurationChangeListener listener) {
142 Assert.assertNotNull(listener);
143 this.listenerSet.addListener(listener);
144 }
145
146 public void addValidator(ConfigurationValidator validator) {
147 Assert.assertNotNull(validator);
148 this.validators.add(validator);
149 }
150
151 public String toString() {
152 return "<Repository for bean of class " + ClassUtils.getShortClassName(this.requiredClass) + "; have bean? "
153 + (this.bean != null) + ">";
154 }
155
156 }
157 |
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