javax.servlet.http.Part Maven / Gradle / Ivy
/*
* 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 javax.servlet.http;
import java.io.IOException;
import java.io.InputStream;
import java.util.Collection;
/**
* This class represents a part as uploaded to the server as part of a multipart/form-data request body.
* The part may represent either an uploaded file or form data.
*
* @since Servlet 3.0
*/
public interface Part {
/**
* Obtain an InputStream that can be used to retrieve the contents of the file.
*
* @return An InputStream for the contents of the file
*
* @throws IOException if an I/O occurs while obtaining the stream
*/
InputStream getInputStream() throws IOException;
/**
* Obtain the content type passed by the browser.
*
* @return The content type passed by the browser or null if not defined.
*/
String getContentType();
/**
* Obtain the name of the field in the multipart form corresponding to this part.
*
* @return The name of the field in the multipart form corresponding to this part.
*/
String getName();
/**
* If this part represents an uploaded file, gets the file name submitted in the upload. Returns {@code null} if no
* file name is available or if this part is not a file upload.
*
* @return the submitted file name or {@code null}.
*
* @since Servlet 3.1
*/
String getSubmittedFileName();
/**
* Obtain the size of this part.
*
* @return The size of the part if bytes
*/
long getSize();
/**
* A convenience method to write an uploaded part to disk. The client code is not concerned with whether or not the
* part is stored in memory, or on disk in a temporary location. They just want to write the uploaded part to a
* file. This method is not guaranteed to succeed if called more than once for the same part. This allows a
* particular implementation to use, for example, file renaming, where possible, rather than copying all of the
* underlying data, thus gaining a significant performance benefit.
*
* @param fileName The location into which the uploaded part should be stored. Relative locations are relative to
* {@link javax.servlet.MultipartConfigElement#getLocation()}
*
* @throws IOException if an I/O occurs while attempting to write the part
*/
void write(String fileName) throws IOException;
/**
* Deletes the underlying storage for a part, including deleting any associated temporary disk file. Although the
* container will delete this storage automatically this method can be used to ensure that this is done at an
* earlier time, thus preserving system resources.
*
* Containers are only required to delete the associated storage when the Part instance is garbage collected. Apache
* Tomcat will delete the associated storage when the associated request has finished processing. Behaviour of other
* containers may be different.
*
* @throws IOException if an I/O occurs while attempting to delete the part
*/
void delete() throws IOException;
/**
* Obtains the value of the specified part header as a String. If there are multiple headers with the same name,
* this method returns the first header in the part. The header name is case insensitive.
*
* @param name Header name
*
* @return The header value or null if the header is not present
*/
String getHeader(String name);
/**
* Obtain all the values of the specified part header.
*
* @param name The name of the header of interest. The header name is case insensitive.
*
* @return All the values of the specified part header. If the part did not include any headers of the specified
* name, this method returns an empty Collection.
*/
Collection getHeaders(String name);
/**
* Get the header names provided for this part.
*
* @return a Collection of all the header names provided for this part.
*/
Collection getHeaderNames();
}