/* * Copyright 2002-2006,2009 The Apache Software Foundation. * * Licensed 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 com.opensymphony.xwork2.conversion.impl; import java.util.Map; /** * <code>EnumTypeConverter</code> * * <!-- START SNIPPET: description --> * This class converts java 5 enums to String and from String[] to enum. * <p/> * One of Java 5's improvements is providing enumeration facility. * Up to now, there existed no enumerations. The only way to simulate was the so-called int Enum pattern: * {code} * public static final int SEASON_WINTER = 0; * public static final int SEASON_SPRING = 1; * public static final int SEASON_SUMMER = 2; * public static final int SEASON_FALL = 3; * {code} * <p/> * Java 5.0 now provides the following construct: * {code} * public static enum Season { WINTER, SPRING, SUMMER, FALL }; * {code} * <!-- END SNIPPET: description --> * * <!-- START SNIPPET: example --> * h3. Implementing Java 5 Enumeration Type Conversion * <p/> * 1. myAction-conversion.properties* * <p/> * Place a myAction-conversion.properties-file in the path of your Action. * Add the following entry to the properties-file: * {code} * nameOfYourField=fullyClassifiedNameOfYourConverter * {code} *   * <p/> * 2. myAction.java* * Your action contains the _enumeration_: * {code} * public enum Criticality {DEBUG, INFO, WARNING, ERROR, FATAL} * {code} *   * * Your action contains the _private field_: * {code} * private myEnum myFieldForEnum; * {code} *   * Your action contains _getters and setters_ for your field: * {code} * public myEnum getCriticality() { * return myFieldForEnum; * } * * public void setCriticality(myEnum myFieldForEnum) { * this.myFieldForEnum= myFieldForEnum; * } * {code} * <p/> * 3. JSP* * <p/> *     In your jsp you can access an enumeration value just normal by using the known <ww:property>-Tag: * {code} * <ww:property value="myField"/> * {code} * <!-- END SNIPPET: example --> * * @author Tamara Cattivelli * @author <a href="mailto:hermanns@aixcept.de">Rainer Hermanns</a> * @version $Id$ * @deprecated Since Struts 2.1.0 as enum support is now built into XWork */ @Deprecated public class EnumTypeConverter extends DefaultTypeConverter { /** * Converts the given object to a given type. How this is to be done is implemented in toClass. The OGNL context, o * and toClass are given. This method should be able to handle conversion in general without any context or object * specified. * * @param context - OGNL context under which the conversion is being done * @param o - the object to be converted * @param toClass - the class that contains the code to convert to enumeration * @return Converted value of type declared in toClass or TypeConverter.NoConversionPossible to indicate that the * conversion was not possible. */ @Override public Object convertValue(Map<String, Object> context, Object o, Class toClass) { if (o instanceof String[]) { return convertFromString(((String[]) o)[0], toClass); } else if (o instanceof String) { return convertFromString((String) o, toClass); } return super.convertValue(context, o, toClass); } /** * Converts one or more String values to the specified class. * @param value - the String values to be converted, such as those submitted from an HTML form * @param toClass - the class to convert to * @return the converted object */ public java.lang.Enum convertFromString(String value, Class toClass) { return Enum.valueOf(toClass, value); } }