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.fileupload2.core;
18
19 /**
20 * Receives progress information. May be used to display a progress bar.
21 */
22 @FunctionalInterface
23 public interface ProgressListener {
24
25 /**
26 * Nop implementation.
27 */
28 ProgressListener NOP = (bytesRead, contentLength, items) -> {
29 // nop
30 };
31
32 /**
33 * Updates the listeners status information.
34 *
35 * @param bytesRead The total number of bytes, which have been read so far.
36 * @param contentLength The total number of bytes, which are being read. May be -1, if this number is unknown.
37 * @param items The number of the field, which is currently being read. (0 = no item so far, 1 = first item is being read, ...)
38 */
39 void update(long bytesRead, long contentLength, int items);
40
41 }