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1
22 package org.jboss.xb.binding;
23
24 import org.jboss.logging.Logger;
25
26 import java.util.List  ;
27 import java.lang.reflect.Constructor ;
28
29
33 public class Immutable
34 {
35 private static final Logger log = Logger.getLogger(Immutable.class);
36
37 public final Class cls;
38
39 final List names = new java.util.ArrayList ();
40
41 final List values = new java.util.ArrayList ();
42
43 public Immutable(Class cls)
44 {
45 this.cls = cls;
46 if(log.isTraceEnabled())
47 {
48 log.trace("created immutable container for " + cls);
49 }
50 }
51
52 public void addChild(String localName, Object child)
53 {
54 if(!names.isEmpty() && names.get(names.size() - 1).equals(localName))
55 {
56 throw new IllegalStateException ("Attempt to add duplicate element " +
57 localName +
58 ": prev value=" +
59 values.get(values.size() - 1) +
60 ", new value=" +
61 child
62 );
63 }
64 names.add(localName);
65 values.add(child);
66
67 if(log.isTraceEnabled())
68 {
69 log.trace("added child " + localName + " for " + cls + ": " + child);
70 }
71 }
72
73 public Object getChild(String localName)
74 {
75 return names.isEmpty() ?
76 null :
77 (names.get(names.size() - 1).equals(localName) ? values.get(values.size() - 1) : null);
78 }
79
80 public Object newInstance()
81 {
82 Constructor ctor = null;
83 Constructor [] ctors = cls.getConstructors();
84
85 if(ctors == null || ctors.length == 0)
86 {
87 throw new JBossXBRuntimeException("The class has no declared constructors: " + cls);
88 }
89
90 for(int i = 0; i < ctors.length; ++i)
91 {
92 Class [] types = ctors[i].getParameterTypes();
93
94 if(types == null || types.length == 0)
95 {
96 throw new IllegalStateException ("Found no-arg constructor for immutable " + cls);
97 }
98
99 if(types.length == values.size())
100 {
101 ctor = ctors[i];
102
103 int typeInd = 0;
104 while(typeInd < types.length)
105 {
106 if(!types[typeInd].isAssignableFrom(values.get(typeInd++).getClass()))
107 {
108 ctor = null;
109 break;
110 }
111 }
112
113 if(ctor != null)
114 {
115 break;
116 }
117 }
118 }
119
120 if(ctor == null)
121 {
122 throw new IllegalStateException ("No constructor in " + cls + " that would take arguments " + values);
123 }
124
125 try
126 {
127 return ctor.newInstance(values.toArray());
128 }
129 catch(Exception e)
130 {
131 throw new IllegalStateException ("Failed to create immutable instance of " +
132 cls +
133 " using arguments: "
134 + values + ": " + e.getMessage()
135 );
136 }
137 }
138 }
139 |
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