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eFaps WebApp provides a web interface as the User Interface for eFaps
which can be easily expanded and altered.
/*
* Copyright 2003 - 2013 The eFaps Team
*
* 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.
*
* Revision: $Rev:1510 $
* Last Changed: $Date:2007-10-18 09:35:40 -0500 (Thu, 18 Oct 2007) $
* Last Changed By: $Author:jmox $
*/
package org.efaps.ui.servlet;
import java.io.IOException;
import java.util.UUID;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.efaps.ci.CIAdminUserInterface;
import org.efaps.db.Checkout;
import org.efaps.db.Instance;
import org.efaps.db.MultiPrintQuery;
import org.efaps.db.QueryBuilder;
import org.efaps.db.SelectBuilder;
import org.efaps.util.EFapsException;
import org.efaps.util.cache.CacheObjectInterface;
import org.efaps.util.cache.CacheReloadException;
import org.efaps.util.cache.InfinispanCache;
import org.infinispan.Cache;
import org.joda.time.DateTime;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* The servlet checks out user interface images depending on the
* administrational name (not file name).
* E.g.:
* /efaps/servlet/image/Admin_UI_Image.
*
* @author The eFaps Team
* @version $Id:ImageServlet.java 1510 2007-10-18 14:35:40Z jmox $
*/
public class ImageServlet
extends HttpServlet
{
/**
* Needed for serialization.
*/
private static final long serialVersionUID = -2469349574113406199L;
/**
* Logging instance used in this class.
*/
private static final Logger LOG = LoggerFactory.getLogger(ImageServlet.class);
/**
* Name of the Cache.
*/
private static final String CACHENAME = "ImageServletCache";
/**
* Used as null for caching purpose.
*/
private static ImageMapper NULL = new ImageMapper(null, null, null, Long.valueOf(0), Long.valueOf(0));
/**
* The method checks the image from the user interface image object out and
* returns them in a output stream to the web client. The name of the user
* interface image object must given as name at the end of the path.
*
* @param _req request variable
* @param _res response variable
* @throws ServletException on error
*/
@Override
protected void doGet(final HttpServletRequest _req,
final HttpServletResponse _res)
throws ServletException
{
String imgName = _req.getRequestURI();
imgName = imgName.substring(imgName.lastIndexOf('/') + 1);
try {
final Cache cache = InfinispanCache.get().getCache(
ImageServlet.CACHENAME);
if (!cache.containsKey(imgName)) {
final QueryBuilder queryBldr = new QueryBuilder(CIAdminUserInterface.Image);
queryBldr.addWhereAttrEqValue(CIAdminUserInterface.Image.Name, imgName);
final MultiPrintQuery multi = queryBldr.getPrint();
final SelectBuilder selLabel = new SelectBuilder().file().label();
final SelectBuilder selLength = new SelectBuilder().file().length();
multi.addSelect(selLabel, selLength);
multi.addAttribute(CIAdminUserInterface.Image.Name,
CIAdminUserInterface.Image.Modified);
multi.executeWithoutAccessCheck();
if (multi.next()) {
final String name = multi.getAttribute(CIAdminUserInterface.Image.Name);
final String file = multi.getSelect(selLabel);
final Long filelength = multi.getSelect(selLength);
final DateTime time = multi.getAttribute(CIAdminUserInterface.Image.Modified);
final ImageMapper imageMapper = new ImageMapper(multi.getCurrentInstance(),
name, file, filelength, time.getMillis());
cache.put(imgName, imageMapper);
} else {
cache.put(imgName, ImageServlet.NULL);
}
}
final ImageMapper imageMapper = cache.get(imgName);
if (imageMapper != null && !imageMapper.equals(ImageServlet.NULL)) {
final Checkout checkout = new Checkout(imageMapper.instance);
_res.setContentType(getServletContext().getMimeType(imageMapper.file));
_res.setContentLength((int) imageMapper.filelength);
_res.setDateHeader("Last-Modified", imageMapper.time);
_res.setDateHeader("Expires", System.currentTimeMillis()
+ (3600 * 1000));
_res.setHeader("Cache-Control", "max-age=3600");
checkout.execute(_res.getOutputStream());
checkout.close();
}
} catch (final IOException e) {
ImageServlet.LOG.error("while reading history data", e);
throw new ServletException(e);
} catch (final CacheReloadException e) {
ImageServlet.LOG.error("while reading history data", e);
throw new ServletException(e);
} catch (final EFapsException e) {
ImageServlet.LOG.error("while reading history data", e);
throw new ServletException(e);
}
}
/**
* The class is used to map from the administrational image name to the
* image file name and image object id.
*/
private static final class ImageMapper
implements CacheObjectInterface
{
/**
* The instance variable stores the administational name of the image.
*/
private final String name;
/**
* The instance variable stores the file name of the image.
*/
private final String file;
/**
* Lenght of the image in long.
*/
private final long filelength;
/**
* Time the image was last retrieved.
*/
private final Long time;
/**
* Instance of this image.
*/
private final Instance instance;
/**
* @param _instance Instance
* @param _name administrational name of the image
* @param _file file name of the image
* @param _filelength lenght of the file
* @param _time time
*/
private ImageMapper(final Instance _instance,
final String _name,
final String _file,
final Long _filelength,
final Long _time)
{
this.name = _name;
this.instance = _instance;
this.file = _file;
this.filelength = _filelength;
this.time = _time;
}
/**
* This is the getter method for instance variable {@link #name}.
*
* @return value of instance variable {@link #name}
* @see #name
*/
public String getName()
{
return this.name;
}
/**
* The method is not needed in this cache implementation, but to
* implement interface {@link CacheInterface} the method is required.
*
* @return always null
*/
public UUID getUUID()
{
return null;
}
/**
* The method is not needed in this cache implementation, but to
* implement interface {@link CacheInterface} the method is required.
*
* @return always 0
*/
public long getId()
{
return 0;
}
}
}