| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package org.apache.commons.jexl2.internal; |
| import java.lang.reflect.InvocationTargetException; |
| /** |
| * Specialized executor to set a property in an object. |
| * @since 2.0 |
| */ |
| public final class PropertySetExecutor extends AbstractExecutor.Set { |
| /** Index of the first character of the set{p,P}roperty. */ |
| private static final int SET_START_INDEX = 3; |
| /** The property. */ |
| private final String property; |
| |
| /** |
| * Creates an instance by attempting discovery of the set method. |
| * @param is the introspector |
| * @param clazz the class to introspect |
| * @param identifier the property to set |
| * @param arg the value to set into the property |
| */ |
| public PropertySetExecutor(Introspector is, Class<?> clazz, String identifier, Object arg) { |
| super(clazz, discover(is, clazz, identifier, arg)); |
| property = identifier; |
| |
| } |
| |
| /** {@inheritDoc} */ |
| @Override |
| public Object getTargetProperty() { |
| return property; |
| } |
| |
| /** {@inheritDoc} */ |
| @Override |
| public Object execute(Object o, Object arg) |
| throws IllegalAccessException, InvocationTargetException { |
| Object[] pargs = {arg}; |
| if (method != null) { |
| method.invoke(o, pargs); |
| } |
| return arg; |
| } |
| |
| /** {@inheritDoc} */ |
| @Override |
| public Object tryExecute(Object o, Object identifier, Object arg) { |
| if (o != null && method != null |
| // ensure method name matches the property name |
| && property.equals(identifier) |
| // object class should be same as executor's method declaring class |
| && objectClass.equals(o.getClass()) |
| // we are guaranteed the method has one parameter since it is a set(x) |
| && (arg == null || method.getParameterTypes()[0].equals(arg.getClass()))) { |
| try { |
| return execute(o, arg); |
| } catch (InvocationTargetException xinvoke) { |
| return TRY_FAILED; // fail |
| } catch (IllegalAccessException xill) { |
| return TRY_FAILED;// fail |
| } |
| } |
| return TRY_FAILED; |
| } |
| |
| |
| /** |
| * Discovers the method for a {@link PropertySet}. |
| * <p>The method to be found should be named "set{P,p}property.</p> |
| *@param is the introspector |
| *@param clazz the class to find the get method from |
| *@param property the name of the property to set |
| *@param arg the value to assign to the property |
| *@return the method if found, null otherwise |
| */ |
| private static java.lang.reflect.Method discover(Introspector is, |
| final Class<?> clazz, String property, Object arg) { |
| // first, we introspect for the set<identifier> setter method |
| Object[] params = {arg}; |
| StringBuilder sb = new StringBuilder("set"); |
| sb.append(property); |
| // uppercase nth char |
| char c = sb.charAt(SET_START_INDEX); |
| sb.setCharAt(SET_START_INDEX, Character.toUpperCase(c)); |
| java.lang.reflect.Method method = is.getMethod(clazz, sb.toString(), params); |
| // lowercase nth char |
| if (method == null) { |
| sb.setCharAt(SET_START_INDEX, Character.toLowerCase(c)); |
| method = is.getMethod(clazz, sb.toString(), params); |
| } |
| |
| return method; |
| } |
| } |
| |