// 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.describe;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.LineNumberReader;
import java.io.Reader;
import java.net.URL;
import org.apache.hivemind.Location;
import org.apache.tapestry.IMarkupWriter;
import org.apache.tapestry.IRequestCycle;
/**
* Adapter for displaying {@link org.apache.hivemind.Location} objects as
* HTML. This may include showing the content of the
* {@link org.apache.hivemind.Resource}, with the line indicated in the
* Location highlighted.
*
* @author Howard M. Lewis Ship
* @since 4.0
*/
public class LocationRenderStrategy implements RenderStrategy
{
/**
* Lines before and after the actual location to display.
*/
private static final int RANGE = 5;
public void renderObject(Object object, IMarkupWriter writer,
IRequestCycle cycle)
{
Location l = (Location) object;
// Always print out the location as a string.
writer.print(l.toString());
int lineNumber = l.getLineNumber();
if (lineNumber < 1) return;
URL url = l.getResource().getResourceURL();
if (url == null) return;
writeResourceContent(writer, url, lineNumber);
}
private void writeResourceContent(IMarkupWriter writer, URL url,
int lineNumber)
{
LineNumberReader reader = null;
try
{
reader = new LineNumberReader(new BufferedReader(
new InputStreamReader(url.openStream())));
writer.beginEmpty("br");
writer.begin("table");
writer.attribute("class", "location-content");
while(true)
{
String line = reader.readLine();
if (line == null) break;
int currentLine = reader.getLineNumber();
if (currentLine > lineNumber + RANGE) break;
if (currentLine < lineNumber - RANGE) continue;
writer.begin("tr");
if (currentLine == lineNumber)
writer.attribute("class", "target-line");
writer.begin("td");
writer.attribute("class", "line-number");
writer.print(currentLine);
writer.end();
writer.begin("td");
writer.print(line);
writer.end("tr");
writer.println();
}
reader.close();
reader = null;
}
catch (Exception ex)
{
// Ignore it.
}
finally
{
writer.end("table");
close(reader);
}
}
private void close(Reader reader)
{
try
{
if (reader != null) reader.close();
}
catch (IOException ex)
{
// Ignore
}
}
}