/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.tomcat.util.http.fileupload;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.ByteArrayInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.UnsupportedEncodingException;
/**
* <p> The default implementation of the
* {@link org.apache.tomcat.util.http.fileupload.FileItem FileItem} interface.
*
* <p> After retrieving an instance of this class from a {@link
* org.apache.tomcat.util.http.fileupload.DiskFileUpload DiskFileUpload} instance (see
* {@link org.apache.tomcat.util.http.fileupload.DiskFileUpload
* #parseRequest(javax.servlet.http.HttpServletRequest)}), you may
* either request all contents of file at once using {@link #get()} or
* request an {@link java.io.InputStream InputStream} with
* {@link #getInputStream()} and process the file without attempting to load
* it into memory, which may come handy with large files.
*
* @author <a href="mailto:Rafal.Krzewski@e-point.pl">Rafal Krzewski</a>
* @author <a href="mailto:sean@informage.net">Sean Legassick</a>
* @author <a href="mailto:jvanzyl@apache.org">Jason van Zyl</a>
* @author <a href="mailto:jmcnally@apache.org">John McNally</a>
* @author <a href="mailto:martinc@apache.org">Martin Cooper</a>
* @author Sean C. Sullivan
*
* @version $Id: DefaultFileItem.java 467222 2006-10-24 03:17:11Z markt $
*/
public class DefaultFileItem
implements FileItem
{
// ----------------------------------------------------------- Data members
/**
* Counter used in unique identifier generation.
*/
private static int counter = 0;
/**
* The name of the form field as provided by the browser.
*/
private String fieldName;
/**
* The content type passed by the browser, or <code>null</code> if
* not defined.
*/
private String contentType;
/**
* Whether or not this item is a simple form field.
*/
private boolean isFormField;
/**
* The original filename in the user's filesystem.
*/
private String fileName;
/**
* The threshold above which uploads will be stored on disk.
*/
private int sizeThreshold;
/**
* The directory in which uploaded files will be stored, if stored on disk.
*/
private File repository;
/**
* Cached contents of the file.
*/
private byte[] cachedContent;
/**
* Output stream for this item.
*/
private DeferredFileOutputStream dfos;
// ----------------------------------------------------------- Constructors
/**
* Constructs a new <code>DefaultFileItem</code> instance.
*
* @param fieldName The name of the form field.
* @param contentType The content type passed by the browser or
* <code>null</code> if not specified.
* @param isFormField Whether or not this item is a plain form field, as
* opposed to a file upload.
* @param fileName The original filename in the user's filesystem, or
* <code>null</code> if not specified.
* @param sizeThreshold The threshold, in bytes, below which items will be
* retained in memory and above which they will be
* stored as a file.
* @param repository The data repository, which is the directory in
* which files will be created, should the item size
* exceed the threshold.
*/
DefaultFileItem(String fieldName, String contentType, boolean isFormField,
String fileName, int sizeThreshold, File repository)
{
this.fieldName = fieldName;
this.contentType = contentType;
this.isFormField = isFormField;
this.fileName = fileName;
this.sizeThreshold = sizeThreshold;
this.repository = repository;
}
// ------------------------------- Methods from javax.activation.DataSource
/**
* Returns an {@link java.io.InputStream InputStream} that can be
* used to retrieve the contents of the file.
*
* @return An {@link java.io.InputStream InputStream} that can be
* used to retrieve the contents of the file.
*
* @exception IOException if an error occurs.
*/
public InputStream getInputStream()
throws IOException
{
if (!dfos.isInMemory())
{
return new FileInputStream(dfos.getFile());
}
if (cachedContent == null)
{
cachedContent = dfos.getData();
}
return new ByteArrayInputStream(cachedContent);
}
/**
* Returns the content type passed by the browser or <code>null</code> if
* not defined.
*
* @return The content type passed by the browser or <code>null</code> if
* not defined.
*/
public String getContentType()
{
return contentType;
}
/**
* Returns the original filename in the client's filesystem.
*
* @return The original filename in the client's filesystem.
*/
public String getName()
{
return fileName;
}
// ------------------------------------------------------- FileItem methods
/**
* Provides a hint as to whether or not the file contents will be read
* from memory.
*
* @return <code>true</code> if the file contents will be read
* from memory; <code>false</code> otherwise.
*/
public boolean isInMemory()
{
return (dfos.isInMemory());
}
/**
* Returns the size of the file.
*
* @return The size of the file, in bytes.
*/
public long getSize()
{
if (cachedContent != null)
{
return cachedContent.length;
}
else if (dfos.isInMemory())
{
return dfos.getData().length;
}
else
{
return dfos.getFile().length();
}
}
/**
* Returns the contents of the file as an array of bytes. If the
* contents of the file were not yet cached in memory, they will be
* loaded from the disk storage and cached.
*
* @return The contents of the file as an array of bytes.
*/
public byte[] get()
{
if (dfos.isInMemory())
{
if (cachedContent == null)
{
cachedContent = dfos.getData();
}
return cachedContent;
}
byte[] fileData = new byte[(int) getSize()];
FileInputStream fis = null;
try
{
fis = new FileInputStream(dfos.getFile());
fis.read(fileData);
}
catch (IOException e)
{
fileData = null;
}
finally
{
if (fis != null)
{
try
{
fis.close();
}
catch (IOException e)
{
// ignore
}
}
}
return fileData;
}
/**
* Returns the contents of the file as a String, using the specified
* encoding. This method uses {@link #get()} to retrieve the
* contents of the file.
*
* @param encoding The character encoding to use.
*
* @return The contents of the file, as a string.
*
* @exception UnsupportedEncodingException if the requested character
* encoding is not available.
*/
public String getString(String encoding)
throws UnsupportedEncodingException
{
return new String(get(), encoding);
}
/**
* Returns the contents of the file as a String, using the default
* character encoding. This method uses {@link #get()} to retrieve the
* contents of the file.
*
* @return The contents of the file, as a string.
*/
public String getString()
{
return new String(get());
}
/**
* A convenience method to write an uploaded item to disk. The client code
* is not concerned with whether or not the item is stored in memory, or on
* disk in a temporary location. They just want to write the uploaded item
* to a file.
* <p>
* This implementation first attempts to rename the uploaded item to the
* specified destination file, if the item was originally written to disk.
* Otherwise, the data will be copied to the specified file.
* <p>
* This method is only guaranteed to work <em>once</em>, the first time it
* is invoked for a particular item. This is because, in the event that the
* method renames a temporary file, that file will no longer be available
* to copy or rename again at a later time.
*
* @param file The <code>File</code> into which the uploaded item should
* be stored.
*
* @exception Exception if an error occurs.
*/
public void write(File file) throws Exception
{
if (isInMemory())
{
FileOutputStream fout = null;
try
{
fout = new FileOutputStream(file);
fout.write(get());
}
finally
{
if (fout != null)
{
fout.close();
}
}
}
else
{
File outputFile = getStoreLocation();
if (outputFile != null)
{
/*
* The uploaded file is being stored on disk
* in a temporary location so move it to the
* desired file.
*/
if (!outputFile.renameTo(file))
{
BufferedInputStream in = null;
BufferedOutputStream out = null;
try
{
in = new BufferedInputStream(
new FileInputStream(outputFile));
out = new BufferedOutputStream(
new FileOutputStream(file));
byte[] bytes = new byte[2048];
int s = 0;
while ((s = in.read(bytes)) != -1)
{
out.write(bytes, 0, s);
}
}
finally
{
try
{
in.close();
}
catch (IOException e)
{
// ignore
}
try
{
out.close();
}
catch (IOException e)
{
// ignore
}
}
}
}
else
{
/*
* For whatever reason we cannot write the
* file to disk.
*/
throw new FileUploadException(
"Cannot write uploaded file to disk!");
}
}
}
/**
* Deletes the underlying storage for a file item, including deleting any
* associated temporary disk file. Although this storage will be deleted
* automatically when the <code>FileItem</code> instance is garbage
* collected, this method can be used to ensure that this is done at an
* earlier time, thus preserving system resources.
*/
public void delete()
{
cachedContent = null;
File outputFile = getStoreLocation();
if (outputFile != null && outputFile.exists())
{
outputFile.delete();
}
}
/**
* Returns the name of the field in the multipart form corresponding to
* this file item.
*
* @return The name of the form field.
*
* @see #setFieldName(java.lang.String)
*
*/
public String getFieldName()
{
return fieldName;
}
/**
* Sets the field name used to reference this file item.
*
* @param fieldName The name of the form field.
*
* @see #getFieldName()
*
*/
public void setFieldName(String fieldName)
{
this.fieldName = fieldName;
}
/**
* Determines whether or not a <code>FileItem</code> instance represents
* a simple form field.
*
* @return <code>true</code> if the instance represents a simple form
* field; <code>false</code> if it represents an uploaded file.
*
* @see #setFormField(boolean)
*
*/
public boolean isFormField()
{
return isFormField;
}
/**
* Specifies whether or not a <code>FileItem</code> instance represents
* a simple form field.
*
* @param state <code>true</code> if the instance represents a simple form
* field; <code>false</code> if it represents an uploaded file.
*
* @see #isFormField()
*
*/
public void setFormField(boolean state)
{
isFormField = state;
}
/**
* Returns an {@link java.io.OutputStream OutputStream} that can
* be used for storing the contents of the file.
*
* @return An {@link java.io.OutputStream OutputStream} that can be used
* for storing the contensts of the file.
*
* @exception IOException if an error occurs.
*/
public OutputStream getOutputStream()
throws IOException
{
if (dfos == null)
{
File outputFile = getTempFile();
dfos = new DeferredFileOutputStream(sizeThreshold, outputFile);
}
return dfos;
}
// --------------------------------------------------------- Public methods
/**
* Returns the {@link java.io.File} object for the <code>FileItem</code>'s
* data's temporary location on the disk. Note that for
* <code>FileItem</code>s that have their data stored in memory,
* this method will return <code>null</code>. When handling large
* files, you can use {@link java.io.File#renameTo(java.io.File)} to
* move the file to new location without copying the data, if the
* source and destination locations reside within the same logical
* volume.
*
* @return The data file, or <code>null</code> if the data is stored in
* memory.
*/
public File getStoreLocation()
{
return dfos.getFile();
}
// ------------------------------------------------------ Protected methods
/**
* Removes the file contents from the temporary storage.
*/
protected void finalize()
{
File outputFile = dfos.getFile();
if (outputFile != null && outputFile.exists())
{
outputFile.delete();
}
}
/**
* Creates and returns a {@link java.io.File File} representing a uniquely
* named temporary file in the configured repository path.
*
* @return The {@link java.io.File File} to be used for temporary storage.
*/
protected File getTempFile()
{
File tempDir = repository;
if (tempDir == null)
{
tempDir = new File(System.getProperty("java.io.tmpdir"));
}
String fileName = "upload_" + getUniqueId() + ".tmp";
File f = new File(tempDir, fileName);
f.deleteOnExit();
return f;
}
// -------------------------------------------------------- Private methods
/**
* Returns an identifier that is unique within the class loader used to
* load this class, but does not have random-like apearance.
*
* @return A String with the non-random looking instance identifier.
*/
private static String getUniqueId()
{
int current;
synchronized (DefaultFileItem.class)
{
current = counter++;
}
String id = Integer.toString(current);
// If you manage to get more than 100 million of ids, you'll
// start getting ids longer than 8 characters.
if (current < 100000000)
{
id = ("00000000" + id).substring(id.length());
}
return id;
}
}
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