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Java > Open Source Codes > bsh > DelayedEvalBshMethod


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33
34 package bsh;
35
36 public class DelayedEvalBshMethod extends BshMethod
37 {
38     String JavaDoc returnTypeDescriptor;
39     BSHReturnType returnTypeNode;
40     String JavaDoc [] paramTypeDescriptors;
41     BSHFormalParameters paramTypesNode;
42
43     // used for the delayed evaluation...
44 transient CallStack callstack;
45     transient Interpreter interpreter;
46
47     /**
48         This constructor is used in class generation. It supplies String type
49         descriptors for return and parameter class types and allows delay of
50         the evaluation of those types until they are requested. It does this
51         by holding BSHType nodes, as well as an evaluation callstack, and
52         interpreter which are called when the class types are requested.
53     */
54     /*
55         Note: technically I think we could get by passing in only the
56         current namespace or perhaps BshClassManager here instead of
57         CallStack and Interpreter. However let's just play it safe in case
58         of future changes - anywhere you eval a node you need these.
59     */
60     DelayedEvalBshMethod(
61         String JavaDoc name,
62         String JavaDoc returnTypeDescriptor, BSHReturnType returnTypeNode,
63         String JavaDoc [] paramNames,
64         String JavaDoc [] paramTypeDescriptors, BSHFormalParameters paramTypesNode,
65         BSHBlock methodBody,
66         NameSpace declaringNameSpace, Modifiers modifiers,
67         CallStack callstack, Interpreter interpreter
68     ) {
69         super( name, null/*returnType*/, paramNames, null/*paramTypes*/,
70             methodBody, declaringNameSpace, modifiers );
71
72         this.returnTypeDescriptor = returnTypeDescriptor;
73         this.returnTypeNode = returnTypeNode;
74         this.paramTypeDescriptors = paramTypeDescriptors;
75         this.paramTypesNode = paramTypesNode;
76         this.callstack = callstack;
77         this.interpreter = interpreter;
78     }
79
80     public String JavaDoc getReturnTypeDescriptor() { return returnTypeDescriptor; }
81
82     public Class JavaDoc getReturnType()
83     {
84         if ( returnTypeNode == null )
85             return null;
86
87         // BSHType will cache the type for us
88 try {
89             return returnTypeNode.evalReturnType( callstack, interpreter );
90         } catch ( EvalError e ) {
91             throw new InterpreterError("can't eval return type: "+e);
92         }
93     }
94
95     public String JavaDoc [] getParamTypeDescriptors() { return paramTypeDescriptors; }
96
97     public Class JavaDoc [] getParameterTypes()
98     {
99         // BSHFormalParameters will cache the type for us
100 try {
101             return (Class JavaDoc [])paramTypesNode.eval( callstack, interpreter );
102         } catch ( EvalError e ) {
103             throw new InterpreterError("can't eval param types: "+e);
104         }
105     }
106 }
107
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