tapestry/tapestry-framework/src/java/org/apache/tapestry/html/RequestDisplay.java

// Copyright 2005 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 org.apache.tapestry.html;

import java.util.Collections;
import java.util.Iterator;
import java.util.List;
import java.util.Properties;
import java.util.StringTokenizer;

import org.apache.tapestry.BaseComponent;
import org.apache.tapestry.IMarkupWriter;
import org.apache.tapestry.IRender;
import org.apache.tapestry.IRequestCycle;
import org.apache.tapestry.describe.ReportStatusHub;
import org.apache.tapestry.web.WebUtils;

/**
 * Supports the {@link org.apache.tapestry.pages.Exception} page by
 * displaying the request, session, servlet context and servlet object for the
 * current request.
 * 
 * @author Howard M. Lewis Ship
 * @since 4.0
 */
public abstract class RequestDisplay extends BaseComponent
{

    private boolean _even;

    // Injected

    public abstract ReportStatusHub getReportStatusHub();

    public void renderSystemProperties(IMarkupWriter writer)
    {
        _even = true;

        Properties p = System.getProperties();

        String pathSeparator = p.getProperty("path.separator");

        writer.begin("div");
        writer.attribute("class", "described-object-title");
        writer.print("JVM System Properties");
        writer.end();
        writer.println();

        writer.begin("table");
        writer.attribute("class", "described-object");

        Iterator i = WebUtils.toSortedList(p.keys()).iterator();

        while(i.hasNext())
        {
            String key = (String) i.next();
            String value = p.getProperty(key);

            renderKeyAndValue(writer, key, value, pathSeparator);
        }

        writer.end();
    }

    private void renderKeyAndValue(IMarkupWriter writer, String key,
            String value, String pathSeparator)
    {
        String[] values = split(key, value, pathSeparator);

        for(int i = 0; i < values.length; i++)
        {
            writer.begin("tr");

            writer.attribute("class", _even ? "even" : "odd");

            _even = !_even;

            writer.begin("th");

            if (i == 0) writer.print(key);

            writer.end();
            writer.begin("td");
            writer.print(values[i]);
            writer.end("tr");
            writer.println();
        }
    }

    private String[] split(String key, String value, String pathSeparator)
    {
        if (!key.endsWith(".path")) return new String[] { value };

        StringTokenizer tokenizer = new StringTokenizer(value, pathSeparator);
        List values = Collections.list(tokenizer);

        return (String[]) values.toArray(new String[values.size()]);
    }

    public IRender getSystemPropertiesRenderer()
    {
        return new IRender()
        {

            public void render(IMarkupWriter writer, IRequestCycle cycle)
            {
                renderSystemProperties(writer);
            }
        };
    }

    public IRender getReportStatusRenderer()
    {
        return new IRender()
        {

            public void render(IMarkupWriter writer, IRequestCycle cycle)
            {
                getReportStatusHub().fireReportStatus(writer);
            }
        };
    }
}