com.oreilly.servlet

Class MultipartRequest

java.lang.Object

com.oreilly.servlet.MultipartRequest

public class MultipartRequest
extends java.lang.Object

A utility class to handle multipart/form-data requests, the kind of requests that support file uploads. This class emulates the interface of HttpServletRequest, making it familiar to use. It uses a "push" model where any incoming files are read and saved directly to disk in the constructor. If you wish to have more flexibility, e.g. write the files to a database, use the "pull" model MultipartParser instead.

This class can receive arbitrarily large files (up to an artificial limit you can set), and fairly efficiently too. It cannot handle nested data (multipart content within multipart content). It can now with the latest release handle internationalized content (such as non Latin-1 filenames).

To avoid collisions and have fine control over file placement, there's a constructor variety that takes a pluggable FileRenamePolicy implementation. A particular policy can choose to rename or change the location of the file before it's written.

See the included upload.war for an example of how to use this class.

The full file upload specification is contained in experimental RFC 1867, available at http://www.ietf.org/rfc/rfc1867.txt.

See Also:

MultipartParser

Field Summary

Fields

Modifier and Type	Field and Description
protected java.util.Hashtable	files
protected java.util.Hashtable	parameters

Constructor Summary

Constructors

Constructor and Description
MultipartRequest(javax.servlet.http.HttpServletRequest request, java.lang.String saveDirectory) Constructs a new MultipartRequest to handle the specified request, saving any uploaded files to the given directory, and limiting the upload size to 1 Megabyte.
MultipartRequest(javax.servlet.http.HttpServletRequest request, java.lang.String saveDirectory, int maxPostSize) Constructs a new MultipartRequest to handle the specified request, saving any uploaded files to the given directory, and limiting the upload size to the specified length.
MultipartRequest(javax.servlet.http.HttpServletRequest request, java.lang.String saveDirectory, int maxPostSize, FileRenamePolicy policy) Constructs a new MultipartRequest to handle the specified request, saving any uploaded files to the given directory, and limiting the upload size to the specified length.
MultipartRequest(javax.servlet.http.HttpServletRequest request, java.lang.String saveDirectory, int maxPostSize, java.lang.String encoding) Constructs a new MultipartRequest to handle the specified request, saving any uploaded files to the given directory, and limiting the upload size to the specified length.
MultipartRequest(javax.servlet.http.HttpServletRequest request, java.lang.String saveDirectory, int maxPostSize, java.lang.String encoding, FileRenamePolicy policy) Constructs a new MultipartRequest to handle the specified request, saving any uploaded files to the given directory, and limiting the upload size to the specified length.
MultipartRequest(javax.servlet.http.HttpServletRequest request, java.lang.String saveDirectory, java.lang.String encoding) Constructs a new MultipartRequest to handle the specified request, saving any uploaded files to the given directory, and limiting the upload size to the specified length.
MultipartRequest(javax.servlet.ServletRequest request, java.lang.String saveDirectory) Constructor with an old signature, kept for backward compatibility.
MultipartRequest(javax.servlet.ServletRequest request, java.lang.String saveDirectory, int maxPostSize) Constructor with an old signature, kept for backward compatibility.

Method Summary

Modifier and Type	Method and Description
java.lang.String	getContentType(java.lang.String name) Returns the content type of the specified file (as supplied by the client browser), or null if the file was not included in the upload.
java.io.File	getFile(java.lang.String name) Returns a File object for the specified file saved on the server's filesystem, or null if the file was not included in the upload.
java.util.Enumeration	getFileNames() Returns the names of all the uploaded files as an Enumeration of Strings.
java.lang.String	getFilesystemName(java.lang.String name) Returns the filesystem name of the specified file, or null if the file was not included in the upload.
java.lang.String	getOriginalFileName(java.lang.String name) Returns the original filesystem name of the specified file (before any renaming policy was applied), or null if the file was not included in the upload.
java.lang.String	getParameter(java.lang.String name) Returns the value of the named parameter as a String, or null if the parameter was not sent or was sent without a value.
java.util.Enumeration	getParameterNames() Returns the names of all the parameters as an Enumeration of Strings.
java.lang.String[]	getParameterValues(java.lang.String name) Returns the values of the named parameter as a String array, or null if the parameter was not sent.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

parameters

protected java.util.Hashtable parameters

files

protected java.util.Hashtable files

Constructor Detail

MultipartRequest

public MultipartRequest(javax.servlet.http.HttpServletRequest request,
                        java.lang.String saveDirectory)
                 throws java.io.IOException

Constructs a new MultipartRequest to handle the specified request, saving any uploaded files to the given directory, and limiting the upload size to 1 Megabyte. If the content is too large, an IOException is thrown. This constructor actually parses the multipart/form-data and throws an IOException if there's any problem reading or parsing the request.

Parameters:

request - the servlet request.

saveDirectory - the directory in which to save any uploaded files.

Throws:

java.io.IOException - if the uploaded content is larger than 1 Megabyte or there's a problem reading or parsing the request.

MultipartRequest

public MultipartRequest(javax.servlet.http.HttpServletRequest request,
                        java.lang.String saveDirectory,
                        int maxPostSize)
                 throws java.io.IOException

Constructs a new MultipartRequest to handle the specified request, saving any uploaded files to the given directory, and limiting the upload size to the specified length. If the content is too large, an IOException is thrown. This constructor actually parses the multipart/form-data and throws an IOException if there's any problem reading or parsing the request.

Parameters:

request - the servlet request.

saveDirectory - the directory in which to save any uploaded files.

maxPostSize - the maximum size of the POST content.

Throws:

java.io.IOException - if the uploaded content is larger than maxPostSize or there's a problem reading or parsing the request.

MultipartRequest

public MultipartRequest(javax.servlet.http.HttpServletRequest request,
                        java.lang.String saveDirectory,
                        java.lang.String encoding)
                 throws java.io.IOException

Constructs a new MultipartRequest to handle the specified request, saving any uploaded files to the given directory, and limiting the upload size to the specified length. If the content is too large, an IOException is thrown. This constructor actually parses the multipart/form-data and throws an IOException if there's any problem reading or parsing the request.

Parameters:

request - the servlet request.

saveDirectory - the directory in which to save any uploaded files.

encoding - the encoding of the response, such as ISO-8859-1

Throws:

java.io.IOException - if the uploaded content is larger than 1 Megabyte or there's a problem reading or parsing the request.

MultipartRequest

public MultipartRequest(javax.servlet.http.HttpServletRequest request,
                        java.lang.String saveDirectory,
                        int maxPostSize,
                        FileRenamePolicy policy)
                 throws java.io.IOException

Constructs a new MultipartRequest to handle the specified request, saving any uploaded files to the given directory, and limiting the upload size to the specified length. If the content is too large, an IOException is thrown. This constructor actually parses the multipart/form-data and throws an IOException if there's any problem reading or parsing the request.

Parameters:

request - the servlet request.

saveDirectory - the directory in which to save any uploaded files.

maxPostSize - the maximum size of the POST content.

policy - the rules for renaming in case of file name collisions

Throws:

java.io.IOException - if the uploaded content is larger than maxPostSize or there's a problem reading or parsing the request.

MultipartRequest

public MultipartRequest(javax.servlet.http.HttpServletRequest request,
                        java.lang.String saveDirectory,
                        int maxPostSize,
                        java.lang.String encoding)
                 throws java.io.IOException

Constructs a new MultipartRequest to handle the specified request, saving any uploaded files to the given directory, and limiting the upload size to the specified length. If the content is too large, an IOException is thrown. This constructor actually parses the multipart/form-data and throws an IOException if there's any problem reading or parsing the request.

Parameters:

request - the servlet request.

saveDirectory - the directory in which to save any uploaded files.

maxPostSize - the maximum size of the POST content.

encoding - the encoding of the response, such as ISO-8859-1

Throws:

java.io.IOException - if the uploaded content is larger than maxPostSize or there's a problem reading or parsing the request.

MultipartRequest

public MultipartRequest(javax.servlet.http.HttpServletRequest request,
                        java.lang.String saveDirectory,
                        int maxPostSize,
                        java.lang.String encoding,
                        FileRenamePolicy policy)
                 throws java.io.IOException

Constructs a new MultipartRequest to handle the specified request, saving any uploaded files to the given directory, and limiting the upload size to the specified length. If the content is too large, an IOException is thrown. This constructor actually parses the multipart/form-data and throws an IOException if there's any problem reading or parsing the request. To avoid file collisions, this constructor takes an implementation of the FileRenamePolicy interface to allow a pluggable rename policy.

Parameters:

request - the servlet request.

saveDirectory - the directory in which to save any uploaded files.

maxPostSize - the maximum size of the POST content.

encoding - the encoding of the response, such as ISO-8859-1

policy - a pluggable file rename policy

Throws:

java.io.IOException - if the uploaded content is larger than maxPostSize or there's a problem reading or parsing the request.

MultipartRequest

public MultipartRequest(javax.servlet.ServletRequest request,
                        java.lang.String saveDirectory)
                 throws java.io.IOException

Constructor with an old signature, kept for backward compatibility. Without this constructor, a servlet compiled against a previous version of this class (pre 1.4) would have to be recompiled to link with this version. This constructor supports the linking via the old signature. Callers must simply be careful to pass in an HttpServletRequest.

Throws:

java.io.IOException

MultipartRequest

public MultipartRequest(javax.servlet.ServletRequest request,
                        java.lang.String saveDirectory,
                        int maxPostSize)
                 throws java.io.IOException

Constructor with an old signature, kept for backward compatibility. Without this constructor, a servlet compiled against a previous version of this class (pre 1.4) would have to be recompiled to link with this version. This constructor supports the linking via the old signature. Callers must simply be careful to pass in an HttpServletRequest.

Throws:

java.io.IOException

Method Detail

getParameterNames

public java.util.Enumeration getParameterNames()

Returns the names of all the parameters as an Enumeration of Strings. It returns an empty Enumeration if there are no parameters.

Returns:

the names of all the parameters as an Enumeration of Strings.

getFileNames

public java.util.Enumeration getFileNames()

Returns the names of all the uploaded files as an Enumeration of Strings. It returns an empty Enumeration if there are no file input fields on the form. Any file input field that's left empty will result in a FilePart with null contents. Each file name is the name specified by the form, not by the user.

Returns:

the names of all the uploaded files as an Enumeration of Strings.

getParameter

public java.lang.String getParameter(java.lang.String name)

Returns the value of the named parameter as a String, or null if the parameter was not sent or was sent without a value. The value is guaranteed to be in its normal, decoded form. If the parameter has multiple values, only the last one is returned (for backward compatibility). For parameters with multiple values, it's possible the last "value" may be null.

Parameters:

name - the parameter name.

Returns:

the parameter value.

getParameterValues

public java.lang.String[] getParameterValues(java.lang.String name)

Returns the values of the named parameter as a String array, or null if the parameter was not sent. The array has one entry for each parameter field sent. If any field was sent without a value that entry is stored in the array as a null. The values are guaranteed to be in their normal, decoded form. A single value is returned as a one-element array.

Parameters:

name - the parameter name.

Returns:

the parameter values.

getFilesystemName

public java.lang.String getFilesystemName(java.lang.String name)

Returns the filesystem name of the specified file, or null if the file was not included in the upload. A filesystem name is the name specified by the user. It is also the name under which the file is actually saved.

Parameters:

name - the html page's file parameter name.

Returns:

the filesystem name of the file.

getOriginalFileName

public java.lang.String getOriginalFileName(java.lang.String name)

Returns the original filesystem name of the specified file (before any renaming policy was applied), or null if the file was not included in the upload. A filesystem name is the name specified by the user.

Parameters:

name - the html page's file parameter name.

Returns:

the original file name of the file.

getContentType

public java.lang.String getContentType(java.lang.String name)

Returns the content type of the specified file (as supplied by the client browser), or null if the file was not included in the upload.

Parameters:

name - the html page's file parameter name.

Returns:

the content type of the file.

getFile

public java.io.File getFile(java.lang.String name)

Returns a File object for the specified file saved on the server's filesystem, or null if the file was not included in the upload.

Parameters:

name - the html page's file parameter name.

Returns:

a File object for the named file.