source: other-projects/trunk/realistic-books/packages/AntInstaller/src/org/tp23/antinstaller/input/OutputField.java@ 19253

/* 
 * Copyright 2005 Paul Hinds
 *
 * 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 org.tp23.antinstaller.input;

import java.util.MissingResourceException;
import java.util.ResourceBundle;

import org.tp23.antinstaller.InstallerContext;
import org.tp23.antinstaller.ValidationException;
/**
 * This is the super class of all "Input types".  It is called OutputField since
 * it handles the base features of "Input types" for outputing text for
 * the user to read.  It also encapsulates some convenience methods for
 * interpreting boolean values from the command line and in configuration files.
 */
public abstract class OutputField {

    // i18n support
    private static ResourceBundle langPack = null;
    private static int commentIdx = 0;
    static{
        try {
            langPack = ResourceBundle.getBundle("resources.LanguagePack");
        } catch (MissingResourceException e) {
            // ignore, signifies no lang packs installed 
        }
    }
    
    /* This is redundant unless language packs are used
     */
    private String name = "comment." + ++commentIdx;
    
    protected String displayText;
    protected String explanatoryText;
    protected ResultContainer resultContainer;
    
    public OutputField() {
        
    }

    /* This is redundant unless language packs are used
     */
    public String getName() {
        return name;
    }

    /* This is redundant unless language packs are used
     */
    public void setName(String name) {
        this.name = name;
    }

    public String getDisplayText() {
        if(langPack != null){
            return langPack.getString(getName() + ".displayText");
        }
        return displayText;
    }

    public void setDisplayText(String displayText) {
        this.displayText = displayText;
    }

    public String getExplanatoryText() {
        if(langPack != null){
            try {
                return langPack.getString(getName() + ".explanatoryText");
            } catch (MissingResourceException e) {
                // ignore and return null explanatoryText is optional
            }
        }
        return explanatoryText;
    }

    public void setExplanatoryText(String explanatoryText) {
        this.explanatoryText = explanatoryText;
    }

    public void setResultContainer(ResultContainer resultContainer) {
        this.resultContainer = resultContainer;
    }

    /**
     * Validate the user input (or lack of it)
     * This method should return false if the validation fails an throw an exception
     * if it is not possible to validate or there is an error.
     *
     * @param cxt InstallerContext
     * @throws ValidationException thrown in error conditions not validation failure
     * @return boolean
     */
    public abstract boolean validate(InstallerContext cxt) throws ValidationException;

    /**
     * Used to validate the configuration, this can be run prior to distributing the
     * installer to check that the config is valid. Will not be used at runtime.
     * @throws ValidationException
     * @return boolean
     */
    public abstract boolean validateObject();

    //////////////////////Static convenience methods

        /** true if specified and true or yes.
         *  N.B it is possible for X,  isTrue(X) == isFalse(X); 
         *  This occurs if the value is null.
         */
        public static boolean isTrue(String value){
            if(value == null)return false;
            return value.equalsIgnoreCase("true") || value.equalsIgnoreCase("yes");
        }
        /** same as isTrue() but default is false if not specified */
        public static boolean isFalse(String value){
            if(value == null)return false;
            return value.equalsIgnoreCase("false") || value.equalsIgnoreCase("no");
        }
        /**
         * Return true if the value is set to true or false, returns false if the value is null
         * @param value String
         * @return boolean
         */
        public static boolean requiredBoolean(String value){
            return isTrue(value) || isFalse(value);
        }
        /**
         * Return true if the value is set to true or false, returns false if the value is null
         * @param value String
         * @return boolean
         */
        public static boolean optionalBoolean(String value){
            return value == null || isTrue(value) || isFalse(value);
        }
}