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.io.entity;
29
30 import java.io.InputStream;
31
32 /**
33 * @since 5.1
34 */
35 public final class EmptyInputStream extends InputStream {
36
37 /**
38 * Singleton instance of EmptyInputStream.
39 */
40 public static final EmptyInputStream INSTANCE = new EmptyInputStream();
41
42 private EmptyInputStream() {
43 // noop.
44 }
45
46 /**
47 * Returns {@code 0}.
48 */
49 @Override
50 public int available() {
51 return 0;
52 }
53
54 /**
55 * Noop.
56 */
57 @Override
58 public void close() {
59 // noop.
60 }
61
62 /**
63 * Noop.
64 */
65 @SuppressWarnings("sync-override")
66 @Override
67 public void mark(final int readLimit) {
68 // noop.
69 }
70
71 /**
72 * Returns {@code true}.
73 */
74 @Override
75 public boolean markSupported() {
76 return true;
77 }
78
79 /**
80 * Returns {@code -1}.
81 */
82 @Override
83 public int read() {
84 return -1;
85 }
86
87 /**
88 * Returns {@code -1}.
89 */
90 @Override
91 public int read(final byte[] buf) {
92 return -1;
93 }
94
95 /**
96 * Returns {@code -1}.
97 */
98 @Override
99 public int read(final byte[] buf, final int off, final int len) {
100 return -1;
101 }
102
103 /**
104 * Noop.
105 */
106 @SuppressWarnings("sync-override")
107 @Override
108 public void reset() {
109 // noop
110 }
111
112 /**
113 * Returns {@code 0}.
114 */
115 @Override
116 public long skip(final long n) {
117 return 0L;
118 }
119 }
120