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21 package org.lobobrowser.js;
22
23 import org.mozilla.javascript.*;
24 import java.lang.reflect.*;
25 import java.util.logging.*;
26 import java.util.*;
27 import org.lobobrowser.util.*;
28
29 public class JavaFunctionObject extends ScriptableObject implements Function {
30 private static final Logger logger = Logger.getLogger(JavaFunctionObject.class.getName());
31 private static final boolean loggableInfo = logger.isLoggable(Level.INFO);
32 private final String  className;
33 private final ArrayList methods = new ArrayList();
34
35 public JavaFunctionObject(String name) {
36 super();
37 this.className = name;
38 }
39
40 public void addMethod(Method m) {
41 this.methods.add(m);
42 }
43
44 public String getClassName() {
45 return this.className;
46 }
47
48 private String getTypeName(Object object) {
49 return object == null ? "[null]" : object.getClass().getName();
50 }
51
52 private Method getBestMethod(Object [] args) {
53 ArrayList methods = this.methods;
54 int size = methods.size();
55 int matchingNumParams = 0;
56 Method matchingMethod = null;
57 for(int i = 0; i < size; i++) {
58 Method m = (Method) methods.get(i);
59 Class [] parameterTypes = m.getParameterTypes();
60 if(args == null) {
61 if(parameterTypes == null || parameterTypes.length == 0) {
62 return m;
63 }
64 }
65 else if(parameterTypes != null && args.length >= parameterTypes.length) {
66 if(Objects.areAssignableTo(args, parameterTypes)) {
67 return m;
68 }
69 if(matchingMethod == null || parameterTypes.length > matchingNumParams) {
70 matchingNumParams = parameterTypes.length;
71 matchingMethod = m;
72 }
73 }
74 }
75 if(size == 0) {
76 throw new IllegalStateException ("zero methods");
77 }
78 return matchingMethod;
79 }
80
81 public Object call(Context cx, Scriptable scope, Scriptable thisObj,
82 Object [] args) {
83 JavaObjectWrapper jcw = (JavaObjectWrapper) thisObj;
84 Method method = this.getBestMethod(args);
85 if(method == null) {
86 throw new EvaluatorException("No method matching " + this.className + " with " + (args == null ? 0 : args.length) + " arguments.");
87 }
88 Class [] actualArgTypes = method.getParameterTypes();
89 int numParams = actualArgTypes.length;
90 Object [] actualArgs = args == null ? new Object [0] : new Object [numParams];
91 boolean linfo = loggableInfo;
92 if(linfo) {
93 Object javaObject = jcw.getJavaObject();
94 logger.info("call(): Calling method " + method.getName() + " on object " + javaObject + " of type " + this.getTypeName(javaObject));
95 }
96 JavaScript manager = JavaScript.getInstance();
97 for(int i = 0; i < numParams; i++) {
98 Object arg = args[i];
99 Object actualArg = manager.getJavaObject(arg, actualArgTypes[i]);
100 if(linfo) {
101 logger.info("call(): For method=" + method.getName() + ": Converted arg=" + arg + " (type=" + this.getTypeName(arg) + ") into actualArg=" + actualArg + ". Type expected by method is " + actualArgTypes[i].getName() + ".");
102 }
103 actualArgs[i] = actualArg;
104 }
105 try {
106 Object raw = method.invoke(jcw.getJavaObject(), actualArgs);
107 return manager.getJavascriptObject(raw, scope);
108 } catch(IllegalAccessException iae) {
109 throw new IllegalStateException ("Unable to call " + this.className + ".", iae);
110 } catch(InvocationTargetException ite) {
111 throw new WrappedException(new InvocationTargetException(ite.getCause(), "Unable to call " + this.className + " on " + jcw.getJavaObject() + "."));
112 } catch(IllegalArgumentException iae) {
113 StringBuffer argTypes = new StringBuffer ();
114 for(int i = 0; i < actualArgs.length; i++) {
115 if(i > 0) {
116 argTypes.append(", ");
117 }
118 argTypes.append(actualArgs[i] == null ? "<null>" : actualArgs[i].getClass().getName());
119 }
120 throw new WrappedException(new IllegalArgumentException ("Unable to call " + this.className + ". Argument types: " + argTypes + ".", iae));
121 }
122 }
123
124 public java.lang.Object getDefaultValue(java.lang.Class hint) {
125 if(loggableInfo) {
126 logger.info("getDefaultValue(): hint=" + hint + ",this=" + this);
127 }
128 if(hint == null || String .class.equals(hint)) {
129 return "function " + this.className;
130 }
131 else {
132 return super.getDefaultValue(hint);
133 }
134 }
135
136 public Scriptable construct(Context cx, Scriptable scope, Object [] args) {
137 throw new UnsupportedOperationException ();
138 }
139 }
140 |
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