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