Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||
Node |
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| 1.0;1 |
1 | package org.apache.commons.ognl; | |
2 | ||
3 | /* | |
4 | * Licensed to the Apache Software Foundation (ASF) under one | |
5 | * or more contributor license agreements. See the NOTICE file | |
6 | * distributed with this work for additional information | |
7 | * regarding copyright ownership. The ASF licenses this file | |
8 | * to you under the Apache License, Version 2.0 (the | |
9 | * "License"); you may not use this file except in compliance | |
10 | * with the License. You may obtain a copy of the License at | |
11 | * | |
12 | * http://www.apache.org/licenses/LICENSE-2.0 | |
13 | * | |
14 | * Unless required by applicable law or agreed to in writing, | |
15 | * software distributed under the License is distributed on an | |
16 | * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY | |
17 | * KIND, either express or implied. See the License for the | |
18 | * specific language governing permissions and limitations | |
19 | * under the License. | |
20 | */ | |
21 | ||
22 | import org.apache.commons.ognl.enhance.ExpressionAccessor; | |
23 | ||
24 | /** | |
25 | * JJTree interface for AST nodes, as modified to handle the OGNL operations getValue and setValue. JJTree's original | |
26 | * comment: All AST nodes must implement this interface. It provides basic machinery for constructing the parent and | |
27 | * child relationships between nodes. | |
28 | * | |
29 | * @author Luke Blanshard (blanshlu@netscape.net) | |
30 | * @author Drew Davidson (drew@ognl.org) | |
31 | */ | |
32 | public interface Node | |
33 | extends JavaSource | |
34 | { | |
35 | ||
36 | /** | |
37 | * This method is called after the node has been made the current node. It indicates that child nodes can now be | |
38 | * added to it. | |
39 | */ | |
40 | void jjtOpen(); | |
41 | ||
42 | /** | |
43 | * This method is called after all the child nodes have been added. | |
44 | */ | |
45 | void jjtClose(); | |
46 | ||
47 | /** | |
48 | * This pair of methods are used to inform the node of its parent. | |
49 | */ | |
50 | void jjtSetParent( Node n ); | |
51 | ||
52 | Node jjtGetParent(); | |
53 | ||
54 | /** | |
55 | * This method tells the node to add its argument to the node's list of children. | |
56 | */ | |
57 | void jjtAddChild( Node n, int i ); | |
58 | ||
59 | /** | |
60 | * This method returns a child node. The children are numbered from zero, left to right. | |
61 | */ | |
62 | Node jjtGetChild( int i ); | |
63 | ||
64 | /** Return the number of children the node has. */ | |
65 | int jjtGetNumChildren(); | |
66 | ||
67 | // OGNL additions to Node: | |
68 | ||
69 | /** | |
70 | * Extracts the value from the given source object that is appropriate for this node within the given context. | |
71 | */ | |
72 | Object getValue( OgnlContext context, Object source ) | |
73 | throws OgnlException; | |
74 | ||
75 | /** | |
76 | * Sets the given value in the given target as appropriate for this node within the given context. | |
77 | */ | |
78 | void setValue( OgnlContext context, Object target, Object value ) | |
79 | throws OgnlException; | |
80 | ||
81 | /** | |
82 | * Gets the compiled bytecode enhanced expression accessor for getting/setting values. | |
83 | * | |
84 | * @return The accessor for this node, or null if none has been compiled for it. | |
85 | */ | |
86 | ExpressionAccessor getAccessor(); | |
87 | ||
88 | /** | |
89 | * Sets a new compiled accessor for this node expression. | |
90 | * | |
91 | * @param accessor The compiled representation of this node. | |
92 | */ | |
93 | void setAccessor( ExpressionAccessor accessor ); | |
94 | ||
95 | ||
96 | /** | |
97 | * Supports the Visitor pattern. The method which corresponds to | |
98 | * the runtime type of this Node will be called. | |
99 | * | |
100 | * @param visitor The visitor to accept. | |
101 | * @param data The second parameter to pass through to visitor.visit | |
102 | * @param <R> The return type of the visitor.visit method. | |
103 | * @param <P> The type of the second parameter type. | |
104 | * @return the value returned by visitor.visit | |
105 | * @throws NullPointerException if visitor is null | |
106 | * @throws RuntimeException if visitor.visit throws an exception. | |
107 | */ | |
108 | <R, P> R accept( NodeVisitor<? extends R, ? super P> visitor, P data ) | |
109 | throws OgnlException; | |
110 | ||
111 | } |