carstore.CarBean.java Source code

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Here is the source code for carstore.CarBean.java

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/*
 * The contents of this file are subject to the terms
 * of the Common Development and Distribution License
 * (the License). You may not use this file except in
 * compliance with the License.
 * 
 * You can obtain a copy of the License at
 * https://javaserverfaces.dev.java.net/CDDL.html or
 * legal/CDDLv1.0.txt. 
 * See the License for the specific language governing
 * permission and limitations under the License.
 * 
 * When distributing Covered Code, include this CDDL
 * Header Notice in each file and include the License file
 * at legal/CDDLv1.0.txt.    
 * If applicable, add the following below the CDDL Header,
 * with the fields enclosed by brackets [] replaced by
 * your own identifying information:
 * "Portions Copyrighted [year] [name of copyright owner]"
 * 
 * [Name of File] [ver.__] [Date]
 * 
 * Copyright 2006 Sun Microsystems Inc. All Rights Reserved
 */

package carstore;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import javax.faces.application.Application;
import javax.faces.application.FacesMessage;
import javax.faces.component.UIComponent;
import javax.faces.component.UIInput;
import javax.faces.component.UISelectItems;
import javax.faces.component.ValueHolder;
import javax.faces.context.FacesContext;
import javax.faces.convert.Converter;
import javax.faces.model.SelectItem;

import java.util.ArrayList;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.MissingResourceException;
import java.util.ResourceBundle;
import java.util.StringTokenizer;

/**
 * <p>This bean encapsulates a car model, including pricing and package
 * choices.  The system allows the user to customize the properties of
 * this bean with the help of the {@link CarCustomizer}.</p>
 *
 * <h3>Data Access</h3>
 *
 * <p>This is the only bean in the system that has complicated access to
 * the persistent store of data.  In the present implementation, this
 * persistent store is in <code>ResourceBundle</code> instances.</p>
 *
 * <p>There are three data source <code>ResourceBundle</code> files
 * used:</p>
 *
 *    <ol>
 *
 *      <li><p><code>&lt;ModelName&gt;</code></p>
 *
 *        <p>This contains the localized content for this model.  There
 *        is a variant of this file for each supported locale, for
 *        example, <code>Jalopy_de.properties</code></p>
 *
 *         </li>
 *
 *      <li><p><code>&lt;Common_properties&gt;</code></p>
 *
 *        <p>This contains the localized content common to all
 *        models.</p>
 *
 *         </li>
 *
 *      <li><p><code>&lt;ModelName_options&gt;</code></p>
 *
 *        <p>This contains the non-localized content for this model,
 *        including the non-localized options.  There is only one
 *        variant of this file for all locales for example,
 *        <code>Jalopy_options.properties</code></p>
 *
 *         </li>
 *
 *   </ol>
 *
 * <p>All files conform to the following convention:</p>
 *
 * <code><pre>
 * key
 * key_componentType
 * key_valueType
 * </pre></code>
 *
 * <p>Where <code>key</code> is the name of an attribute of this car.
 * For example, <code>basePrice</code>, or <code>description</code>.
 * <code>key_componentType</code> is the component type of the
 * <code>UIComponent</code> subclass to be used to represent this
 * attribute in the page, for example <code>SelectManyMenu</code>.
 * <code>key_valueType</code> is the data type of the value of the
 * <code>UIComponent</code>, for example <code>java.lang.Integer</code>.
 * For all non-String valueTypes.</p>
 *
 * <p>When the bean is instantiated, we load both of the above
 * properties files and iterate over the keys in each one.  For each
 * key, we look at the <code>componentType</code> and ask the
 * <code>Application</code> to create a component of that type.  We
 * store that <code>UIComponent</code> instance in our
 * <code>components</code> <code>Map</code> under the name
 * <code>key</code>.  We look at the <code>valueType</code> for the
 * <code>key</code>.  For non <code>java.lang.String</code> types, we
 * ask the <code>Application</code> for a <code>Converter</code>
 * instance for that class.  If found, we use it to convert the value
 * for the <code>key</code> to the appropriate type and store that as
 * the <code>value</code> of the <code>UIComponent</code> instance.</p>
 */

public class CarBean extends Object {

    protected static final Log log = LogFactory.getLog(CarBean.class);

    /**
     * <p>The message identifier of the Message to be created if
     * the conversion fails.  The message format string for this
     * message may optionally include a <code>{0}</code>
     * placeholder, which will be replaced by the object and value.</p>
     */
    public static final String CONVERTER_ERROR_MESSAGE_ID = "carstore.Converter_Error";

    //
    // Relationship Instance Variables
    //

    /**
     * Localized labels
     */

    private ResourceBundle resources = null;

    /**
     * Price data
     */
    private ResourceBundle priceData = null;

    /**
     * Keys: String attribute name, such as engine. Values: UIComponent
     * for the attribute
     */

    private Map components = null;

    /**
     * Keys: String attribute name, such as engine. Values: String value
     * of the component named by key in our components Map.
     */

    private Map attributes = null;

    // 
    // Constructors
    //

    public CarBean() {
        this.init(CarStore.DEFAULT_MODEL_PROPERTIES);
    }

    public CarBean(String bundleName) {
        this.init(bundleName);
    }

    /**
     * <p>Initialize our components <code>Map</code> as described in the
     * class documentation.</p>
     *
     * <p>Create a wrapper <code>Map</code> around the components
     * <code>Map</code> that exposes the String converted value of each
     * component.</p>
     */

    private void init(String bundleName) {
        FacesContext context = FacesContext.getCurrentInstance();
        ResourceBundle data = null;
        Enumeration keys = null;
        components = new HashMap();

        // load the labels
        resources = ResourceBundle.getBundle(CarStore.CARSTORE_PREFIX + ".bundles.Resources",
                context.getViewRoot().getLocale());

        // load the prices
        priceData = ResourceBundle.getBundle(CarStore.CARSTORE_PREFIX + ".bundles.OptionPrices");

        // populate the locale-specific information
        if (log.isDebugEnabled()) {
            log.debug("Loading bundle: " + bundleName + ".");
        }
        data = ResourceBundle.getBundle(bundleName, context.getViewRoot().getLocale());
        if (log.isDebugEnabled()) {
            log.debug("Bundle " + bundleName + " loaded. Reading properties...");
        }
        initComponentsFromProperties(context, data);
        if (log.isDebugEnabled()) {
            log.debug("done.");
        }

        // populate the non-locale-specific information common to all cars
        if (log.isDebugEnabled()) {
            log.debug("Loading bundle: Common_options.");
        }
        data = ResourceBundle.getBundle(CarStore.CARSTORE_PREFIX + ".bundles.Common_options");
        if (log.isDebugEnabled()) {
            log.debug("Bundle Common_options loaded. Reading properties...");
        }
        initComponentsFromProperties(context, data);
        if (log.isDebugEnabled()) {
            log.debug("done.");
        }

        // populate the non-locale-specific information specific to each car
        if (log.isDebugEnabled()) {
            log.debug("Loading bundle: " + bundleName + "_options.");
        }
        data = ResourceBundle.getBundle(bundleName + "_options");
        if (log.isDebugEnabled()) {
            log.debug("Bundle " + bundleName + "_options loaded. Reading properties...");
        }
        initComponentsFromProperties(context, data);
        if (log.isDebugEnabled()) {
            log.debug("done.");
        }

        // create a read-only Map exposing the values of all of our
        // components.
        attributes = new Map() {
            public void clear() {
                CarBean.this.components.clear();
            }

            public boolean containsKey(Object key) {
                return CarBean.this.components.containsKey(key);
            }

            public boolean containsValue(Object value) {
                throw new UnsupportedOperationException();
            }

            public java.util.Set entrySet() {
                throw new UnsupportedOperationException();
            }

            public boolean equals(Object o) {
                throw new UnsupportedOperationException();
            }

            public Object get(Object key) {
                UIComponent component = null;
                Converter converter = null;
                Object result = null;
                if (null == key) {
                    return null;
                }
                if (null != (component = (UIComponent) CarBean.this.components.get(key))) {
                    // if this component can have a Converter
                    if (component instanceof ValueHolder) {
                        // try to get it
                        converter = ((ValueHolder) component).getConverter();
                        result = ((ValueHolder) component).getValue();
                    }

                    // if we do have a value
                    if (null != result) {
                        // and we do have a converter
                        if (null != converter) {
                            // convert the value to String
                            result = converter.getAsString(FacesContext.getCurrentInstance(), component, result);
                        }
                    }
                }
                return result;
            }

            public int hashCode() {
                return CarBean.this.components.hashCode();
            }

            public boolean isEmpty() {
                return CarBean.this.components.isEmpty();
            }

            public java.util.Set keySet() {
                return CarBean.this.components.keySet();
            }

            public Object put(Object k, Object v) {
                throw new UnsupportedOperationException();
            }

            public void putAll(Map t) {
                throw new UnsupportedOperationException();
            }

            public Object remove(Object k) {
                throw new UnsupportedOperationException();
            }

            public int size() {
                return CarBean.this.components.size();
            }

            public java.util.Collection values() {
                ArrayList result = new ArrayList();
                Iterator keys = keySet().iterator();
                while (keys.hasNext()) {
                    result.add(get(keys.next()));
                }
                return result;
            }
        };

    }

    /**
     * <p>For each entry in data, create component and cause it to be
     * populated with values.</p>
     */

    private void initComponentsFromProperties(FacesContext context, ResourceBundle data) {
        Application application = context.getApplication();
        Enumeration keys = data.getKeys();
        String key = null, value = null, componentType = null, valueType = null;
        UIComponent component = null;

        // populate the map
        while (keys.hasMoreElements()) {
            key = (String) keys.nextElement();
            if (key == null) {
                continue;
            }
            // skip secondary keys.
            if (-1 != key.indexOf("_")) {
                continue;
            }
            value = data.getString(key);
            componentType = data.getString(key + "_componentType");
            valueType = data.getString(key + "_valueType");
            if (log.isDebugEnabled()) {
                log.debug("populating map for " + key + "\n" + "\n\tvalue: " + value + "\n\tcomponentType: "
                        + componentType + "\n\tvalueType: " + valueType);
            }
            // create the component for this componentType
            component = application.createComponent(componentType);
            populateComponentWithValue(context, component, componentType, value, valueType);
            components.put(key, component);
        }
    }

    /**
     * <p>populate the argument component with values, being sensitive
     * to the possible multi-nature of the values, and to the type of
     * the values.</p>
     */

    private void populateComponentWithValue(FacesContext context, UIComponent component, String componentType,
            String value, String valueType) {
        Application application = context.getApplication();
        Converter converter = null;
        UISelectItems items = null;

        // if we need a converter, and can have a converter
        if (!valueType.equals("java.lang.String") && component instanceof ValueHolder) {
            // if so create it,
            try {
                converter = application.createConverter(CarStore.loadClass(valueType, this));
            } catch (ClassNotFoundException cne) {
                FacesMessage errMsg = MessageFactory.getMessage(CONVERTER_ERROR_MESSAGE_ID,
                        (new Object[] { valueType }));
                throw new IllegalStateException(errMsg.getSummary());
            }
            // add it to our component,
            ((ValueHolder) component).setConverter(converter);
        }

        // if this component is a SelectOne or SelectMany, take special action
        if (isMultiValue(componentType)) {
            // create a UISelectItems instance
            items = new UISelectItems();
            items.setValue(parseStringIntoArrayList(context, component, value, valueType, converter));
            // add it to the component
            component.getChildren().add(items);
        } else {
            // we have a single value
            if (null != converter) {
                component.getAttributes().put("value", converter.getAsObject(context, component, value));
            } else {
                component.getAttributes().put("value", value);
            }
        }
    }

    /**
     * @return true if componentType starts with SelectMany or SelectOne
     */
    private boolean isMultiValue(String componentType) {
        if (null == componentType) {
            return false;
        }
        return (componentType.startsWith("javax.faces.SelectMany")
                || componentType.startsWith("javax.faces.SelectOne"));
    }

    /**
     * Tokenizes the passed in String which is a comma separated string of
     * option values that serve as keys into the main resources file.
     * For example, optionStr could be "Disc,Drum", which corresponds to
     * brake options available for the chosen car. This String is tokenized
     * and used as key into the main resource file to get the localized option
     * values and stored in the passed in ArrayList.
     */
    public ArrayList parseStringIntoArrayList(FacesContext context, UIComponent component, String value,
            String valueType, Converter converter) {
        ArrayList optionsList = null;
        int i = 0;
        Object optionValue = null;
        String optionKey = null, optionLabel = null;
        Map nonLocalizedOptionValues = null;

        if (value == null) {
            return null;
        }
        StringTokenizer st = new StringTokenizer(value, ",");
        optionsList = new ArrayList((st.countTokens()) + 1);
        while (st.hasMoreTokens()) {
            optionKey = st.nextToken();
            try {
                optionLabel = resources.getString(optionKey);
            } catch (MissingResourceException e) {
                // if we can't find a hit, the key is the label
                optionLabel = optionKey;
            }

            if (null != converter) {
                // PENDING deal with the converter case
            } else {
                optionsList.add(new SelectItem(optionKey, optionLabel));
            }
        }
        return optionsList;
    }

    public String updatePricing() {
        getCurrentPrice();
        return null;
    }

    public Integer getCurrentPrice() {
        // go through our options and try to get the prices
        int sum = ((Integer) ((ValueHolder) getComponents().get("basePrice")).getValue()).intValue();
        Iterator iter = getComponents().keySet().iterator();
        String key = null;
        Object value = null;
        UIComponent component = null;
        while (iter.hasNext()) {
            key = (String) iter.next();
            component = (UIComponent) getComponents().get(key);
            value = component.getAttributes().get("value");
            if (null == value || (!(component instanceof UIInput))) {
                continue;
            }

            // if the value is a String, see if we have priceData for it
            if (value instanceof String) {
                try {
                    sum += Integer.valueOf(priceData.getString((String) value)).intValue();
                } catch (NumberFormatException e) {
                }
            }
            // if the value is a Boolean, look up the price by name
            else if (value instanceof Boolean && ((Boolean) value).booleanValue()) {
                try {
                    sum += Integer.valueOf(priceData.getString(key)).intValue();
                } catch (NumberFormatException e) {
                }
            } else if (value instanceof Number) {
                sum += ((Number) value).intValue();
            }
        }
        Integer result = new Integer(sum);
        // store the new price into the component for currentPrice
        ((ValueHolder) getComponents().get("currentPrice")).setValue(result);
        return result;
    }

    public Map getComponents() {
        return components;
    }

    public Map getAttributes() {
        return attributes;
    }

}