| 1 | // Copyright 2004-2007 Jean-Francois Poilpret |
| 2 | // |
| 3 | // Licensed under the Apache License, Version 2.0 (the "License"); |
| 4 | // you may not use this file except in compliance with the License. |
| 5 | // You may obtain a copy of the License at |
| 6 | // |
| 7 | // http://www.apache.org/licenses/LICENSE-2.0 |
| 8 | // |
| 9 | // Unless required by applicable law or agreed to in writing, software |
| 10 | // distributed under the License is distributed on an "AS IS" BASIS, |
| 11 | // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 12 | // See the License for the specific language governing permissions and |
| 13 | // limitations under the License. |
| 14 | |
| 15 | package net.sourceforge.hiveutils.util; |
| 16 | |
| 17 | import java.lang.reflect.Method; |
| 18 | import java.util.HashMap; |
| 19 | import java.util.Map; |
| 20 | |
| 21 | /** |
| 22 | * Default implementation to generate a mapping between public methods of a |
| 23 | * source class (or interface) into equivalent methods (same name, same |
| 24 | * arguments, compatible returned type, but possibly different thrown |
| 25 | * exceptions). |
| 26 | * |
| 27 | * @author Jean-Francois Poilpret |
| 28 | */ |
| 29 | public class DefaultMethodMappingBuilder implements MethodMappingBuilder |
| 30 | { |
| 31 | /** |
| 32 | * The method analyses all public methods of source class. For each method: |
| 33 | * <ul> |
| 34 | * <li>search a public method with the name and arguments list in target</li> |
| 35 | * <li>check the returned type of the target method is assignable to the |
| 36 | * the returned type of the source method</li> |
| 37 | * </ul> |
| 38 | * <p> |
| 39 | * If a <code>source</code> method has no <code>target</code> method with |
| 40 | * matches for name and arguments, then a warning is generated and that |
| 41 | * method will not appear in the returned <code>Map</code>. |
| 42 | */ |
| 43 | public Map<Method, Method> buildMapping( Class source, |
| 44 | Class target, |
| 45 | MethodMappingErrorHandler handler) |
| 46 | { |
| 47 | Map<Method, Method> methodsMap = new HashMap<Method, Method>(); |
| 48 | for (Method src: source.getMethods()) |
| 49 | { |
| 50 | Method tgt = mapMethod(src, target, handler); |
| 51 | if (tgt != null) |
| 52 | { |
| 53 | methodsMap.put(src, tgt); |
| 54 | } |
| 55 | } |
| 56 | return methodsMap; |
| 57 | } |
| 58 | |
| 59 | protected Method mapMethod(Method source, |
| 60 | Class targetClass, |
| 61 | MethodMappingErrorHandler handler) |
| 62 | { |
| 63 | try |
| 64 | { |
| 65 | // Find equivalent method in implementation |
| 66 | Method target = targetClass.getMethod( source.getName(), |
| 67 | source.getParameterTypes()); |
| 68 | // Check return types are compatible |
| 69 | Class<?> srcReturn = source.getReturnType(); |
| 70 | Class<?> tgtReturn = target.getReturnType(); |
| 71 | if ( srcReturn.isAssignableFrom(tgtReturn) |
| 72 | || handler.handleIncompatibleMethods(source, target)) |
| 73 | { |
| 74 | return target; |
| 75 | } |
| 76 | return null; |
| 77 | } |
| 78 | catch (NoSuchMethodException e) |
| 79 | { |
| 80 | handler.handleNonExistingMethod(source, targetClass); |
| 81 | return null; |
| 82 | } |
| 83 | } |
| 84 | } |