com.vaadin.server.FileResource Maven / Gradle / Ivy
/*
* Copyright (C) 2000-2024 Vaadin Ltd
*
* This program is available under Vaadin Commercial License and Service Terms.
*
* See for the full
* license.
*/
package com.vaadin.server;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import com.vaadin.util.FileTypeResolver;
/**
* FileResources are files or directories on local filesystem. The
* files and directories are served through URI:s to the client terminal and
* thus must be registered to an URI context before they can be used. The
* resource is automatically registered to the application when it is created.
*
* @author Vaadin Ltd.
* @since 3.0
*/
@SuppressWarnings("serial")
public class FileResource implements ConnectorResource {
/**
* Default buffer size for this stream resource.
*/
private int bufferSize = 0;
/**
* File where the downloaded content is fetched from.
*/
private File sourceFile;
/**
* Default cache time for this stream resource.
*/
private long cacheTime = DownloadStream.DEFAULT_CACHETIME;
/**
* Creates a new file resource for providing given file for client
* terminals.
*
* @param sourceFile
* the file that should be served.
*/
public FileResource(File sourceFile) {
if (sourceFile == null) {
throw new IllegalArgumentException("File cannot be null");
}
setSourceFile(sourceFile);
}
@Override
public DownloadStream getStream() {
try {
final DownloadStream ds = new DownloadStream(
new FileInputStream(sourceFile), getMIMEType(),
getFilename());
ds.setParameter("Content-Length",
String.valueOf(sourceFile.length()));
ds.setBufferSize(getBufferSize());
ds.setCacheTime(getCacheTime());
return ds;
} catch (final FileNotFoundException e) {
throw new RuntimeException(
"File not found: " + sourceFile.getName(), e);
}
}
/**
* Gets the source file.
*
* @return the source File.
*/
public File getSourceFile() {
return sourceFile;
}
/**
* Sets the source file.
*
* @param sourceFile
* the source file to set.
*/
private void setSourceFile(File sourceFile) {
this.sourceFile = sourceFile;
}
@Override
public String getFilename() {
return sourceFile.getName();
}
@Override
public String getMIMEType() {
return FileTypeResolver.getMIMEType(sourceFile);
}
/**
* Gets the length of cache expiration time. This gives the adapter the
* possibility cache streams sent to the client. The caching may be made in
* adapter or at the client if the client supports caching. Default is
* DownloadStream.DEFAULT_CACHETIME.
*
* @return Cache time in milliseconds.
*/
public long getCacheTime() {
return cacheTime;
}
/**
* Sets the length of cache expiration time. This gives the adapter the
* possibility cache streams sent to the client. The caching may be made in
* adapter or at the client if the client supports caching. Zero or negative
* value disables the caching of this stream.
*
* @param cacheTime
* the cache time in milliseconds.
*/
public void setCacheTime(long cacheTime) {
this.cacheTime = cacheTime;
}
/**
* Gets the size of the download buffer used for this resource.
*
*
* If the buffer size is 0, the buffer size is decided by the terminal
* adapter. The default value is 0.
*
*
* @return the size of the buffer in bytes.
*/
public int getBufferSize() {
return bufferSize;
}
/**
* Sets the size of the download buffer used for this resource.
*
* @param bufferSize
* the size of the buffer in bytes.
*/
public void setBufferSize(int bufferSize) {
this.bufferSize = bufferSize;
}
}