1
2
3 /*
4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
5 *
6 * Copyright 1997-2007 Sun Microsystems, Inc. All rights reserved.
7 *
8 * Portions Copyright Apache Software Foundation.
9 *
10 * The contents of this file are subject to the terms of either the GNU
11 * General Public License Version 2 only ("GPL") or the Common Development
12 * and Distribution License("CDDL") (collectively, the "License"). You
13 * may not use this file except in compliance with the License. You can obtain
14 * a copy of the License at https://glassfish.dev.java.net/public/CDDL+GPL.html
15 * or glassfish/bootstrap/legal/LICENSE.txt. See the License for the specific
16 * language governing permissions and limitations under the License.
17 *
18 * When distributing the software, include this License Header Notice in each
19 * file and include the License file at glassfish/bootstrap/legal/LICENSE.txt.
20 * Sun designates this particular file as subject to the "Classpath" exception
21 * as provided by Sun in the GPL Version 2 section of the License file that
22 * accompanied this code. If applicable, add the following below the License
23 * Header, with the fields enclosed by brackets [] replaced by your own
24 * identifying information: "Portions Copyrighted [year]
25 * [name of copyright owner]"
26 *
27 * Contributor(s):
28 *
29 * If you wish your version of this file to be governed by only the CDDL or
30 * only the GPL Version 2, indicate your decision by adding "[Contributor]
31 * elects to include this software in this distribution under the [CDDL or GPL
32 * Version 2] license." If you don't indicate a single choice of license, a
33 * recipient has the option to distribute your version of this file under
34 * either the CDDL, the GPL Version 2 or to extend the choice of license to
35 * its licensees as provided above. However, if you add GPL Version 2 code
36 * and therefore, elected the GPL Version 2 license, then the option applies
37 * only if the new code is made subject to such option by the copyright
38 * holder.
39 */
40
41 package javax.servlet;
42
43 import java.io.InputStream;
44 import java.io.IOException;
45
46 /**
47 *
48 * Provides an input stream for reading binary data from a client
49 * request, including an efficient <code>readLine</code> method
50 * for reading data one line at a time. With some protocols, such
51 * as HTTP POST and PUT, a <code>ServletInputStream</code>
52 * object can be used to read data sent from the client.
53 *
54 * <p>A <code>ServletInputStream</code> object is normally retrieved via
55 * the {@link ServletRequest#getInputStream} method.
56 *
57 *
58 * <p>This is an abstract class that a servlet container implements.
59 * Subclasses of this class
60 * must implement the <code>java.io.InputStream.read()</code> method.
61 *
62 *
63 * @author Various
64 *
65 * @see ServletRequest
66 *
67 */
68
69 public abstract class ServletInputStream extends InputStream {
70
71
72
73 /**
74 * Does nothing, because this is an abstract class.
75 *
76 */
77
78 protected ServletInputStream() { }
79
80
81
82
83 /**
84 *
85 * Reads the input stream, one line at a time. Starting at an
86 * offset, reads bytes into an array, until it reads a certain number
87 * of bytes or reaches a newline character, which it reads into the
88 * array as well.
89 *
90 * <p>This method returns -1 if it reaches the end of the input
91 * stream before reading the maximum number of bytes.
92 *
93 *
94 *
95 * @param b an array of bytes into which data is read
96 *
97 * @param off an integer specifying the character at which
98 * this method begins reading
99 *
100 * @param len an integer specifying the maximum number of
101 * bytes to read
102 *
103 * @return an integer specifying the actual number of bytes
104 * read, or -1 if the end of the stream is reached
105 *
106 * @exception IOException if an input or output exception has occurred
107 *
108 */
109
110 public int readLine(byte[] b, int off, int len) throws IOException {
111
112 if (len <= 0) {
113 return 0;
114 }
115 int count = 0, c;
116
117 while ((c = read()) != -1) {
118 b[off++] = (byte)c;
119 count++;
120 if (c == '\n' || count == len) {
121 break;
122 }
123 }
124 return count > 0 ? count : -1;
125 }
126 }
127
128
129
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