/*
* Copyright 2005 Joe Walker
*
* 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.directwebremoting.convert;
import java.awt.image.BufferedImage;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import javax.imageio.ImageIO;
import javax.servlet.http.HttpServletRequest;
import org.directwebremoting.Container;
import org.directwebremoting.ConversionException;
import org.directwebremoting.WebContextFactory;
import org.directwebremoting.extend.AbstractConverter;
import org.directwebremoting.extend.ContainerUtil;
import org.directwebremoting.extend.DataUrlDownloadManager;
import org.directwebremoting.extend.DownloadManager;
import org.directwebremoting.extend.FormField;
import org.directwebremoting.extend.InboundVariable;
import org.directwebremoting.extend.NonNestedOutboundVariable;
import org.directwebremoting.extend.OutboundContext;
import org.directwebremoting.extend.OutboundVariable;
import org.directwebremoting.io.FileTransfer;
import org.directwebremoting.io.InputStreamFactory;
import org.directwebremoting.util.BrowserDetect;
import org.directwebremoting.util.CopyUtils;
import org.directwebremoting.util.UserAgent;
/**
* The FileConverter can only convert inbound files, convertOutbound is not
* supported.
* Files come from an <input type="file"/> on the client.
* @author Lance Semmens [uklance at gmail dot com]
* @author Joe Walker [joe at getahead dot org]
* @author Niklas Johansson [niklas dot json at gmail dot com]
*/
public class FileConverter extends AbstractConverter
{
/* (non-Javadoc)
* @see org.directwebremoting.extend.Converter#convertInbound(java.lang.Class, org.directwebremoting.extend.InboundVariable, org.directwebremoting.extend.InboundContext)
*/
public Object convertInbound(Class<?> paramType, InboundVariable data) throws ConversionException
{
if (data.isNull())
{
return null;
}
try
{
final FormField formField = data.getFormField();
if (paramType == FileTransfer.class)
{
InputStreamFactory inFactory = new InputStreamFactory()
{
public InputStream getInputStream() throws IOException
{
return formField.getInputStream();
}
public void close() throws IOException
{
formField.getInputStream().close();
}
};
return new FileTransfer(formField.getName(), formField.getMimeType(), formField.getFileSize(), inFactory);
}
else if (paramType == InputStream.class)
{
return formField.getInputStream();
}
else if (paramType == BufferedImage.class)
{
return ImageIO.read(formField.getInputStream());
}
else if (paramType.isArray() && paramType.getComponentType() == Byte.TYPE)
{
InputStream in = formField.getInputStream();
ByteArrayOutputStream out = new ByteArrayOutputStream();
CopyUtils.copy(in, out);
return out.toByteArray();
}
}
catch (IOException ex)
{
throw new ConversionException(paramType, ex);
}
throw new ConversionException(paramType, "File conversion is not possible for a " + paramType);
}
/* (non-Javadoc)
* @see org.directwebremoting.extend.Converter#convertOutbound(java.lang.Object, org.directwebremoting.extend.OutboundContext)
*/
public OutboundVariable convertOutbound(final Object object, OutboundContext outboundContext) throws ConversionException
{
if (object == null)
{
return new NonNestedOutboundVariable("null");
}
try
{
FileTransfer transfer;
if (object instanceof BufferedImage)
{
transfer = new FileTransfer((BufferedImage) object, "png");
}
else if (object instanceof InputStream)
{
final InputStream in = (InputStream) object;
transfer = new FileTransfer("download.dat", "binary/octet-stream", -1, new InputStreamFactory()
{
public InputStream getInputStream() throws IOException
{
return in;
}
public void close() throws IOException
{
in.close();
}
});
}
else if (object instanceof FileTransfer)
{
transfer = (FileTransfer) object;
}
else if (object.getClass().isArray() && object.getClass().getComponentType() == Byte.TYPE)
{
transfer = new FileTransfer("download.dat", "binary/octet-stream", (byte[]) object);
}
else
{
throw new ConversionException(object.getClass());
}
Container container = WebContextFactory.get().getContainer();
boolean preferDataUrlSchema = ContainerUtil.getBooleanSetting(container, "preferDataUrlSchema", false);
DownloadManager downloadManager;
if (preferDataUrlSchema && isDataUrlAvailable())
{
downloadManager = new DataUrlDownloadManager();
}
else
{
downloadManager = container.getBean(DownloadManager.class);
}
String url = downloadManager.addFileTransfer(transfer);
return new NonNestedOutboundVariable(url);
}
catch (IOException ex)
{
throw new ConversionException(getClass(), ex);
}
}
/**
* Is the data: URL allowed by the current browser.
* @return true if data: is allowed
*/
protected boolean isDataUrlAvailable()
{
HttpServletRequest request = WebContextFactory.get().getHttpServletRequest();
return BrowserDetect.atLeast(request, UserAgent.IE, 8) ||
BrowserDetect.atLeast(request, UserAgent.Gecko, 20041107) ||
BrowserDetect.atLeast(request, UserAgent.AppleWebKit, 2) ||
BrowserDetect.atLeast(request, UserAgent.Opera, 8);
}
}