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25 package org.snipsnap.config;
26
27 import java.lang.reflect.Field  ;
28 import java.lang.reflect.InvocationHandler ;
29 import java.lang.reflect.Method ;
30 import java.lang.reflect.Proxy ;
31 import java.lang.reflect.InvocationTargetException ;
32 import java.util.HashMap ;
33 import java.util.Map ;
34 import java.util.StringTokenizer ;
35 import java.util.Arrays ;
36
37 public class ConfigurationProxy implements InvocationHandler {
38 private Map methodCache = new HashMap ();
39 private Map propertyMethodCache = new HashMap ();
40
41 private ConfigurationMap config = null;
42 private Method getMethod, setMethod;
43 private Method staticGetMethod, staticSetMethod;
44 private Map propertyMethodMap;
45
46 public ConfigurationProxy(ConfigurationMap config) {
47 this.config = config;
48 try {
49 staticGetMethod = config.getClass().getMethod("getGlobal", new Class []{String .class});
51 staticSetMethod = config.getClass().getMethod("setGlobal", new Class []{String .class, String .class});
52 methodCache.put(staticGetMethod.toString(), staticGetMethod);
53 methodCache.put(staticGetMethod.toString(), staticSetMethod);
54
55 getMethod = config.getClass().getMethod("get", new Class []{String .class});
57 setMethod = config.getClass().getMethod("set", new Class []{String .class, String .class});
58 methodCache.put(getMethod.toString(), getMethod);
59 methodCache.put(setMethod.toString(), setMethod);
60 } catch (Exception e) {
61 System.err.println("FATAL ERROR: unable to get get/set methods of configuration map");
62 e.printStackTrace();
63 getMethod = null;
64 }
65
66 propertyMethodMap = new HashMap ();
67 Field [] fields = Configuration.class.getFields();
68 for (int fieldCount = 0; fieldCount < fields.length; fieldCount++) {
69 try {
70 String value = (String ) fields[fieldCount].get(Configuration.class);
71 propertyMethodMap.put("get" + getCamlCase(value, "app."), value);
72 propertyMethodMap.put("set" + getCamlCase(value, "app."), value);
73 propertyMethodCache.put("get" + getCamlCase(value, "app."), getMethod);
74 propertyMethodCache.put("set" + getCamlCase(value, "app."), setMethod);
75 } catch (Exception e) {
76 System.err.println("ERROR unable to load property names: " + e);
77 e.printStackTrace();
78 }
79 }
80
81 fields = Globals.class.getFields();
82 for(int fieldCount = 0; fieldCount < fields.length; fieldCount++) {
83 try {
84 String value = (String ) fields[fieldCount].get(Globals.class);
85 propertyMethodMap.put("get" + getCamlCase(value, "app."), value);
86 propertyMethodMap.put("set" + getCamlCase(value, "app."), value);
87 propertyMethodCache.put("get" + getCamlCase(value, "app."), staticGetMethod);
88 propertyMethodCache.put("set" + getCamlCase(value, "app."), staticSetMethod);
89 } catch (Exception e) {
90 System.err.println("ERROR unable to load global property names: " + e);
91 e.printStackTrace();
92 }
93 }
94 }
95
96
103 private String getCamlCase(String name, String prefix) {
104 if (name.startsWith(prefix)) {
105 name = name.substring(prefix.length());
106 }
107 StringTokenizer tokenizer = new StringTokenizer (name, ".", false);
108 StringBuffer result = new StringBuffer ();
109 while (tokenizer.hasMoreTokens()) {
110 String token = tokenizer.nextToken();
111 result.append(token.substring(0, 1).toUpperCase());
112 if (token.length() > 1) {
113 result.append(token.substring(1));
114 }
115 }
116 return result.toString();
117 }
118
119 public Object invoke(Object proxy, Method method, Object [] args) throws Throwable {
121 Object result = null;
122 Object [] invokeArgs = args;
123
124
126 Method targetMethod = getTargetMethod(method);
127
128 if (targetMethod == null) {
130 String methodName = method.getName();
131 targetMethod = (Method )propertyMethodCache.get(methodName);
132 if(args != null) {
135 invokeArgs = new Object [args.length + 1];
136 System.arraycopy(args, 0, invokeArgs, 1, args.length);
137 } else {
138 invokeArgs = new Object [1];
139 }
140 invokeArgs[0] = propertyMethodMap.get(methodName);
141 }
142
143 try {
144 result = targetMethod.invoke(config, invokeArgs);
148 } catch (IllegalAccessException e) {
149 System.err.println("ConfigurationProxy: illegal access to method: "+targetMethod);
150 } catch (IllegalArgumentException e) {
151 System.err.println("ConfigurationProxy: illegal arguments: "+Arrays.asList(invokeArgs));
152 e.printStackTrace();
153 } catch (InvocationTargetException e) {
154 e.getTargetException().printStackTrace();
155
156 }
157 return result;
159 }
160
161 private Method getTargetMethod(Method method) {
162 String methodKey = method.toString();
163 if (methodCache.containsKey(methodKey)) {
164 return (Method ) methodCache.get(methodKey);
165 } else {
166 try {
167 Method targetMethod = config.getClass().getMethod(method.getName(), method.getParameterTypes());
168 methodCache.put(targetMethod.toString(), targetMethod);
169 return targetMethod;
170 } catch (NoSuchMethodException e) {
171 } catch (SecurityException e) {
173 e.printStackTrace();
174 }
175 }
176 return null;
177 }
178
179 public static Configuration proxy = null;
181
182 public static Configuration getInstance() {
183 if (proxy == null) {
184 newInstance();
185 }
186 return proxy;
187 }
188
189 public static Configuration newInstance() {
190 return newProxyInstance(new ConfigurationMap());
191 }
192
193 public static Configuration newInstance(Configuration config) {
194 return newProxyInstance(new ConfigurationMap(config));
195 }
196
197 private static Configuration newProxyInstance(ConfigurationMap config) {
198 proxy = (Configuration) Proxy.newProxyInstance(config.getClass().getClassLoader(),
199 new Class []{Configuration.class, Globals.class},
200 new ConfigurationProxy(config));
201 return proxy;
202 }
203
204 }
205 |
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