1 /*
2 * ====================================================================
3 * Licensed to the Apache Software Foundation (ASF) under one
4 * or more contributor license agreements. See the NOTICE file
5 * distributed with this work for additional information
6 * regarding copyright ownership. The ASF licenses this file
7 * to you under the Apache License, Version 2.0 (the
8 * "License"); you may not use this file except in compliance
9 * with the License. You may obtain a copy of the License at
10 *
11 * http://www.apache.org/licenses/LICENSE-2.0
12 *
13 * Unless required by applicable law or agreed to in writing,
14 * software distributed under the License is distributed on an
15 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
16 * KIND, either express or implied. See the License for the
17 * specific language governing permissions and limitations
18 * under the License.
19 * ====================================================================
20 *
21 * This software consists of voluntary contributions made by many
22 * individuals on behalf of the Apache Software Foundation. For more
23 * information on the Apache Software Foundation, please see
24 * <http://www.apache.org/>.
25 *
26 */
27
28 package org.apache.hc.core5.http.impl.io;
29
30 import java.io.IOException;
31 import java.io.OutputStream;
32
33 import org.apache.hc.core5.http.StreamClosedException;
34 import org.apache.hc.core5.http.io.SessionOutputBuffer;
35 import org.apache.hc.core5.util.Args;
36
37 /**
38 * Output stream that cuts off after a defined number of bytes. This class
39 * is used to send content of HTTP messages where the end of the content entity
40 * is determined by the value of the {@code Content-Length header}.
41 * Entities transferred using this stream can be maximum {@link Long#MAX_VALUE}
42 * long.
43 * <p>
44 * Note that this class NEVER closes the underlying stream, even when
45 * {@link #close()} gets called. Instead, the stream will be marked as closed
46 * and no further output will be permitted.
47 *
48 * @since 4.0
49 */
50 public class ContentLengthOutputStream extends OutputStream {
51
52 private final SessionOutputBuffer buffer;
53 private final OutputStream outputStream;
54
55 /**
56 * The maximum number of bytes that can be written the stream. Subsequent
57 * write operations will be ignored.
58 */
59 private final long contentLength;
60
61 /** Total bytes written */
62 private long total;
63
64 /** True if the stream is closed. */
65 private boolean closed;
66
67 /**
68 * Default constructor.
69 *
70 * @param buffer Session output buffer
71 * @param outputStream Output stream
72 * @param contentLength The maximum number of bytes that can be written to
73 * the stream. Subsequent write operations will be ignored.
74 *
75 * @since 4.0
76 */
77 public ContentLengthOutputStream(final SessionOutputBuffer buffer, final OutputStream outputStream, final long contentLength) {
78 super();
79 this.buffer = Args.notNull(buffer, "Session output buffer");
80 this.outputStream = Args.notNull(outputStream, "Output stream");
81 this.contentLength = Args.notNegative(contentLength, "Content length");
82 }
83
84 /**
85 * Finishes writing to the underlying stream, but does NOT close the underlying stream.
86 * @throws IOException If an I/O problem occurs.
87 */
88 @Override
89 public void close() throws IOException {
90 if (!this.closed) {
91 this.closed = true;
92 this.buffer.flush(this.outputStream);
93 }
94 }
95
96 @Override
97 public void flush() throws IOException {
98 this.buffer.flush(this.outputStream);
99 }
100
101 @Override
102 public void write(final byte[] b, final int off, final int len) throws IOException {
103 if (this.closed) {
104 throw new StreamClosedException();
105 }
106 if (this.total < this.contentLength) {
107 final long max = this.contentLength - this.total;
108 int chunk = len;
109 if (chunk > max) {
110 chunk = (int) max;
111 }
112 this.buffer.write(b, off, chunk, this.outputStream);
113 this.total += chunk;
114 }
115 }
116
117 @Override
118 public void write(final byte[] b) throws IOException {
119 write(b, 0, b.length);
120 }
121
122 @Override
123 public void write(final int b) throws IOException {
124 if (this.closed) {
125 throw new StreamClosedException();
126 }
127 if (this.total < this.contentLength) {
128 this.buffer.write(b, this.outputStream);
129 this.total++;
130 }
131 }
132
133 }