net.sourceforge.stripes.action.ValidationErrorReportResolution Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of stripes Show documentation
Stripes web framework jar, including tag library.
There is a newer version: 1.7.0-async-beta
/* Copyright 2010 Ben Gunter
 *
 * 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 net.sourceforge.stripes.action;

import java.io.PrintWriter;
import java.util.List;
import java.util.Locale;
import java.util.MissingResourceException;
import java.util.ResourceBundle;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import net.sourceforge.stripes.controller.StripesFilter;
import net.sourceforge.stripes.exception.SourcePageNotFoundException;
import net.sourceforge.stripes.tag.ErrorsTag;
import net.sourceforge.stripes.util.HtmlUtil;
import net.sourceforge.stripes.util.Log;
import net.sourceforge.stripes.validation.ValidationError;

/**
 * A resolution that streams a simple HTML response to the client detailing the validation errors
 * that apply for an {@link ActionBeanContext}.
 * 
 * @author Ben Gunter
 * @since Stripes 1.5.5
 */
public class ValidationErrorReportResolution implements Resolution {
    private static final Log log = Log.getInstance(ValidationErrorReportResolution.class);
    private ActionBeanContext context;

    /** Construct a new instance to report validation errors in the specified context. */
    public ValidationErrorReportResolution(ActionBeanContext context) {
        this.context = context;
    }

    /** Get the action bean context on which the validation errors occurred. */
    public ActionBeanContext getContext() {
        return context;
    }

    public void execute(HttpServletRequest request, HttpServletResponse response) throws Exception {
        // log an exception for the stack trace
        SourcePageNotFoundException exception = new SourcePageNotFoundException(getContext());
        log.error(exception);

        // start the HTML error report
        response.setContentType("text/html");
        PrintWriter writer = response.getWriter();
        writer.println("");
        writer.println("Stripes validation error report
");
        writer.println(HtmlUtil.encode(exception.getMessage()));
        writer.println("
Validation errors
");
        sendErrors(request, response);
        writer.println("");
    }

    /**
     * Called by {@link #execute(HttpServletRequest, HttpServletResponse)} to write the actual
     * validation errors to the client. The {@code header}, {@code footer}, {@code beforeError} and
     * {@code afterError} resources are used by this method.
     * 
     * @param request The servlet request.
     * @param response The servlet response.
     */
    protected void sendErrors(HttpServletRequest request, HttpServletResponse response)
            throws Exception {
        // Output all errors in a standard format
        Locale locale = request.getLocale();
        ResourceBundle bundle = null;

        try {
            bundle = StripesFilter.getConfiguration().getLocalizationBundleFactory()
                    .getErrorMessageBundle(locale);
        }
        catch (MissingResourceException mre) {
            log.warn(getClass().getName(), " could not find the error messages resource bundle. ",
                    "As a result default headers/footers etc. will be used. Check that ",
                    "you have a StripesResources.properties in your classpath (unless ",
                    "of course you have configured a different bundle).");
        }

        // Fetch the header and footer
        String header = getResource(bundle, "header", ErrorsTag.DEFAULT_HEADER);
        String footer = getResource(bundle, "footer", ErrorsTag.DEFAULT_FOOTER);
        String openElement = getResource(bundle, "beforeError", "");
        String closeElement = getResource(bundle, "afterError", "");

        // Write out the error messages
        PrintWriter writer = response.getWriter();
        writer.write(header);

        for (List list : getContext().getValidationErrors().values()) {
            for (ValidationError fieldError : list) {
                writer.write(openElement);
                writer.write(HtmlUtil.encode(fieldError.getMessage(locale)));
                writer.write(closeElement);
            }
        }

        writer.write(footer);
    }

    /**
     * Utility method that is used to lookup the resources used for the error header, footer, and
     * the strings that go before and after each error.
     * 
     * @param bundle the bundle to look up the resource from
     * @param name the name of the resource to lookup (prefixes will be added)
     * @param fallback a value to return if no resource can be found
     * @return the value to use for the named resource
     */
    protected String getResource(ResourceBundle bundle, String name, String fallback) {
        if (bundle == null) {
            return fallback;
        }

        String resource;
        try {
            resource = bundle.getString("stripes.errors." + name);
        }
        catch (MissingResourceException mre) {
            resource = fallback;
        }

        return resource;
    }
}