| 1 | package org.apache.velocity.runtime.parser.node; |
| 2 | /* |
| 3 | * Copyright 2000-2002,2004 The Apache Software Foundation. |
| 4 | * |
| 5 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 6 | * you may not use this file except in compliance with the License. |
| 7 | * You may obtain a copy of the License at |
| 8 | * |
| 9 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 10 | * |
| 11 | * Unless required by applicable law or agreed to in writing, software |
| 12 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 13 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 14 | * See the License for the specific language governing permissions and |
| 15 | * limitations under the License. |
| 16 | */ |
| 17 | |
| 18 | import java.lang.reflect.InvocationTargetException; |
| 19 | |
| 20 | import org.apache.velocity.util.introspection.Introspector; |
| 21 | |
| 22 | import org.apache.velocity.runtime.RuntimeLogger; |
| 23 | |
| 24 | /** |
| 25 | * Returned the value of object property when executed. |
| 26 | */ |
| 27 | public class PropertyExecutor extends AbstractExecutor |
| 28 | { |
| 29 | protected Introspector introspector = null; |
| 30 | |
| 31 | protected String methodUsed = null; |
| 32 | |
| 33 | public PropertyExecutor(RuntimeLogger r, Introspector ispctr, |
| 34 | Class clazz, String property) |
| 35 | { |
| 36 | rlog = r; |
| 37 | introspector = ispctr; |
| 38 | |
| 39 | discover(clazz, property); |
| 40 | } |
| 41 | |
| 42 | protected void discover(Class clazz, String property) |
| 43 | { |
| 44 | /* |
| 45 | * this is gross and linear, but it keeps it straightforward. |
| 46 | */ |
| 47 | |
| 48 | try |
| 49 | { |
| 50 | char c; |
| 51 | StringBuffer sb; |
| 52 | |
| 53 | Object[] params = { }; |
| 54 | |
| 55 | /* |
| 56 | * start with get<property> |
| 57 | * this leaves the property name |
| 58 | * as is... |
| 59 | */ |
| 60 | sb = new StringBuffer("get"); |
| 61 | sb.append(property); |
| 62 | |
| 63 | methodUsed = sb.toString(); |
| 64 | |
| 65 | method = introspector.getMethod(clazz, methodUsed, params); |
| 66 | |
| 67 | if (method != null) |
| 68 | return; |
| 69 | |
| 70 | /* |
| 71 | * now the convenience, flip the 1st character |
| 72 | */ |
| 73 | |
| 74 | sb = new StringBuffer("get"); |
| 75 | sb.append(property); |
| 76 | |
| 77 | c = sb.charAt(3); |
| 78 | |
| 79 | if (Character.isLowerCase(c)) |
| 80 | { |
| 81 | sb.setCharAt(3, Character.toUpperCase(c)); |
| 82 | } |
| 83 | else |
| 84 | { |
| 85 | sb.setCharAt(3, Character.toLowerCase(c)); |
| 86 | } |
| 87 | |
| 88 | methodUsed = sb.toString(); |
| 89 | method = introspector.getMethod(clazz, methodUsed, params); |
| 90 | |
| 91 | if (method != null) |
| 92 | return; |
| 93 | |
| 94 | } |
| 95 | catch(Exception e) |
| 96 | { |
| 97 | rlog.error("PROGRAMMER ERROR : PropertyExector() : " + e ); |
| 98 | } |
| 99 | } |
| 100 | |
| 101 | |
| 102 | /** |
| 103 | * Execute method against context. |
| 104 | */ |
| 105 | public Object execute(Object o) |
| 106 | throws IllegalAccessException, InvocationTargetException |
| 107 | { |
| 108 | if (method == null) |
| 109 | return null; |
| 110 | |
| 111 | return method.invoke(o, null); |
| 112 | } |
| 113 | } |
| 114 | |
| 115 | |