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/* * $Id: FormPropertyConfig.java 471754 2006-11-06 14:55:09Z husted $ * * 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.struts.config; import org.apache.commons.beanutils.ConvertUtils; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import java.lang.reflect.Array; import java.lang.reflect.InvocationTargetException; /** * <p>A JavaBean representing the configuration information of a * <code><form-property></code> element in a Struts configuration * file.<p> * * @version $Rev: 471754 $ $Date: 2005-11-12 11:52:08 -0500 (Sat, 12 Nov 2005)$ * @since Struts 1.1 */ public class FormPropertyConfig extends BaseConfig { /** * The logging instance */ private static final Log log = LogFactory.getLog(FormPropertyConfig.class); // ----------------------------------------------------- Instance Variables // ------------------------------------------------------------- Properties /** * String representation of the initial value for this property. */ protected String initial = null; /** * The JavaBean property name of the property described by this element. */ protected String name = null; /** * <p>The conditions under which the property described by this element * should be reset to its <code>initial</code> value when the form's * <code>reset</code> method is called.</p> <p>This may be set to true (to * always reset the property) or a comma-separated list of HTTP request * methods.</p> * * @since Struts 1.3 */ protected String reset = null; /** * <p>The size of the array to be created if this property is an array * type and there is no specified <code>initial</code> value. This value * must be non-negative.</p> * * @since Struts 1.1 */ protected int size = 0; /** * The fully qualified Java class name of the implementation class of this * bean property, optionally followed by <code>[]</code> to indicate that * the property is indexed. */ protected String type = null; // ----------------------------------------------------------- Constructors /** * Standard no-arguments constructor for dynamic instantiation. */ public FormPropertyConfig() { super(); } /** * Constructor that preconfigures the relevant properties. * * @param name Name of this property * @param type Fully qualified class name of this property * @param initial Initial value of this property (if any) */ public FormPropertyConfig(String name, String type, String initial) { this(name, type, initial, 0); } /** * Constructor that preconfigures the relevant properties. * * @param name Name of this property * @param type Fully qualified class name of this property * @param initial Initial value of this property (if any) * @param reset The conditions under which this property will be reset * to its initial value. */ public FormPropertyConfig(String name, String type, String initial, String reset) { this(name, type, initial, reset, 0); } /** * Constructor that preconfigures the relevant properties. * * @param name Name of this property * @param type Fully qualified class name of this property * @param initial Initial value of this property (if any) * @param size Size of the array to be created if this property is an * array with no defined initial value */ public FormPropertyConfig(String name, String type, String initial, int size) { this(name, type, initial, null, size); } /** * Constructor that preconfigures the relevant properties. * * @param name Name of this property * @param type Fully qualified class name of this property * @param initial Initial value of this property (if any) * @param size Size of the array to be created if this property is an * array with no defined initial value * @param reset The conditions under which this property will be reset * to its initial value. */ public FormPropertyConfig(String name, String type, String initial, String reset, int size) { super(); setName(name); setType(type); setInitial(initial); setReset(reset); setSize(size); } public String getInitial() { return (this.initial); } public void setInitial(String initial) { if (configured) { throw new IllegalStateException("Configuration is frozen"); } this.initial = initial; } public String getName() { return (this.name); } public void setName(String name) { if (configured) { throw new IllegalStateException("Configuration is frozen"); } this.name = name; } public String getReset() { return (this.reset); } public void setReset(String reset) { if (configured) { throw new IllegalStateException("Configuration is frozen"); } this.reset = reset; } public int getSize() { return (this.size); } public void setSize(int size) { if (configured) { throw new IllegalStateException("Configuration is frozen"); } if (size < 0) { throw new IllegalArgumentException("size < 0"); } this.size = size; } public String getType() { return (this.type); } public void setType(String type) { if (configured) { throw new IllegalStateException("Configuration is frozen"); } this.type = type; } /** * Return a Class corresponds to the value specified for the * <code>type</code> property, taking into account the trailing "[]" for * arrays (as well as the ability to specify primitive Java types). */ public Class getTypeClass() { // Identify the base class (in case an array was specified) String baseType = getType(); boolean indexed = false; if (baseType.endsWith("[]")) { baseType = baseType.substring(0, baseType.length() - 2); indexed = true; } // Construct an appropriate Class instance for the base class Class baseClass = null; if ("boolean".equals(baseType)) { baseClass = Boolean.TYPE; } else if ("byte".equals(baseType)) { baseClass = Byte.TYPE; } else if ("char".equals(baseType)) { baseClass = Character.TYPE; } else if ("double".equals(baseType)) { baseClass = Double.TYPE; } else if ("float".equals(baseType)) { baseClass = Float.TYPE; } else if ("int".equals(baseType)) { baseClass = Integer.TYPE; } else if ("long".equals(baseType)) { baseClass = Long.TYPE; } else if ("short".equals(baseType)) { baseClass = Short.TYPE; } else { ClassLoader classLoader = Thread.currentThread().getContextClassLoader(); if (classLoader == null) { classLoader = this.getClass().getClassLoader(); } try { baseClass = classLoader.loadClass(baseType); } catch (ClassNotFoundException ex) { log.error("Class '" + baseType + "' not found for property '" + name + "'"); baseClass = null; } } // Return the base class or an array appropriately if (indexed) { return (Array.newInstance(baseClass, 0).getClass()); } else { return (baseClass); } } // --------------------------------------------------------- Public Methods /** * <p>Return an object representing the initial value of this property. * This is calculated according to the following algorithm:</p> * * <ul> * * <li>If the value you have specified for the <code>type</code> property * represents an array (i.e. it ends with "[]"): * * <ul> * * <li>If you have specified a value for the <code>initial</code> * property, <code>ConvertUtils.convert</code> will be called to convert * it into an instance of the specified array type.</li> * * <li>If you have not specified a value for the <code>initial</code> * property, an array of the length specified by the <code>size</code> * property will be created. Each element of the array will be * instantiated via the zero-args constructor on the specified class (if * any). Otherwise, <code>null</code> will be returned.</li> * * </ul></li> * * <li>If the value you have specified for the <code>type</code> property * does not represent an array: * * <ul> * * <li>If you have specified a value for the <code>initial</code> * property, <code>ConvertUtils.convert</code> will be called to convert * it into an object instance.</li> * * <li>If you have not specified a value for the <code>initial</code> * attribute, Struts will instantiate an instance via the zero-args * constructor on the specified class (if any). Otherwise, * <code>null</code> will be returned.</li> * * </ul></li> * * </ul> */ public Object initial() { Object initialValue = null; try { Class clazz = getTypeClass(); if (clazz.isArray()) { if (initial != null) { initialValue = ConvertUtils.convert(initial, clazz); } else { initialValue = Array.newInstance(clazz.getComponentType(), size); if (!(clazz.getComponentType().isPrimitive())) { for (int i = 0; i < size; i++) { try { Array.set(initialValue, i, clazz.getComponentType().newInstance()); } catch (Throwable t) { log.error("Unable to create instance of " + clazz.getName() + " for property=" + name + ", type=" + type + ", initial=" + initial + ", size=" + size + "."); //FIXME: Should we just dump the entire application/module ? } } } } } else { if (initial != null) { initialValue = ConvertUtils.convert(initial, clazz); } else { initialValue = clazz.newInstance(); } } } catch (Throwable t) { initialValue = null; } return (initialValue); } /** * <p>Inherit values that have not been overridden from the provided * config object. Subclasses overriding this method should verify that * the given parameter is of a class that contains a property it is trying * to inherit:</p> * <pre> * if (config instanceof MyCustomFormPropertyConfig) { * MyCustomFormPropertyConfig myConfig = * (MyCustomFormPropertyConfig) config; * * if (getMyCustomProp() == null) { * setMyCustomProp(myConfig.getMyCustomProp()); * } * } * </pre> * * @param config The object that this instance will be inheriting its * values from. */ public void inheritFrom(FormPropertyConfig config) throws IllegalAccessException, InvocationTargetException, InstantiationException, ClassNotFoundException { if (configured) { throw new IllegalStateException("Configuration is frozen"); } if (getInitial() == null) { setInitial(config.getInitial()); } if (getName() == null) { setName(config.getName()); } if (getSize() == 0) { setSize(config.getSize()); } if (getType() == null) { setType(config.getType()); } inheritProperties(config); } /** * Return a String representation of this object. */ public String toString() { StringBuffer sb = new StringBuffer("FormPropertyConfig["); sb.append("name="); sb.append(this.name); sb.append(",type="); sb.append(this.type); sb.append(",initial="); sb.append(this.initial); sb.append(",reset="); sb.append(this.reset); sb.append("]"); return (sb.toString()); } }