1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one or more 3 * contributor license agreements. See the NOTICE file distributed with 4 * this work for additional information regarding copyright ownership. 5 * The ASF licenses this file to You under the Apache License, Version 2.0 6 * (the "License"); you may not use this file except in compliance with 7 * the License. You may obtain a copy of the License at 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the License for the specific language governing permissions and 15 * limitations under the License. 16 */ 17 package org.apache.commons.fileupload; 18 19 import java.io.IOException; 20 import java.io.InputStream; 21 22 /** 23 * <p> This interface provides access to a file or form item that was 24 * received within a {@code multipart/form-data} POST request. 25 * The items contents are retrieved by calling {@link #openStream()}.</p> 26 * <p>Instances of this class are created by accessing the 27 * iterator, returned by 28 * {@link FileUploadBase#getItemIterator(RequestContext)}.</p> 29 * <p><em>Note</em>: There is an interaction between the iterator and 30 * its associated instances of {@link FileItemStream}: By invoking 31 * {@link java.util.Iterator#hasNext()} on the iterator, you discard all data, 32 * which hasn't been read so far from the previous data.</p> 33 */ 34 public interface FileItemStream extends FileItemHeadersSupport { 35 36 /** 37 * This exception is thrown, if an attempt is made to read 38 * data from the {@link InputStream}, which has been returned 39 * by {@link FileItemStream#openStream()}, after 40 * {@link java.util.Iterator#hasNext()} has been invoked on the 41 * iterator, which created the {@link FileItemStream}. 42 */ 43 class ItemSkippedException extends IOException { 44 45 /** 46 * The exceptions serial version UID, which is being used 47 * when serializing an exception instance. 48 */ 49 private static final long serialVersionUID = -7280778431581963740L; 50 51 /** 52 * Constructs a new instance. 53 */ 54 public ItemSkippedException() { 55 // empty 56 } 57 58 } 59 60 /** 61 * Returns the content type passed by the browser or {@code null} if 62 * not defined. 63 * 64 * @return The content type passed by the browser or {@code null} if 65 * not defined. 66 */ 67 String getContentType(); 68 69 /** 70 * Returns the name of the field in the multipart form corresponding to 71 * this file item. 72 * 73 * @return The name of the form field. 74 */ 75 String getFieldName(); 76 77 /** 78 * Returns the original file name in the client's file system, as provided by 79 * the browser (or other client software). In most cases, this will be the 80 * base file name, without path information. However, some clients, such as 81 * the Opera browser, do include path information. 82 * 83 * @return The original file name in the client's file system. 84 */ 85 String getName(); 86 87 /** 88 * Determines whether or not a {@code FileItem} instance represents 89 * a simple form field. 90 * 91 * @return {@code true} if the instance represents a simple form 92 * field; {@code false} if it represents an uploaded file. 93 */ 94 boolean isFormField(); 95 96 /** 97 * Creates an {@link InputStream}, which allows to read the 98 * items contents. 99 * 100 * @return The input stream, from which the items data may 101 * be read. 102 * @throws IllegalStateException The method was already invoked on 103 * this item. It is not possible to recreate the data stream. 104 * @throws IOException An I/O error occurred. 105 * @see ItemSkippedException 106 */ 107 InputStream openStream() throws IOException; 108 109 }