001// *************************************************************************************************************************** 002// * Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE file * 003// * distributed with this work for additional information regarding copyright ownership. The ASF licenses this file * 004// * to you under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance * 005// * with the License. You may obtain a copy of the License at * 006// * * 007// * http://www.apache.org/licenses/LICENSE-2.0 * 008// * * 009// * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an * 010// * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the * 011// * specific language governing permissions and limitations under the License. * 012// *************************************************************************************************************************** 013package org.apache.juneau.rest.util; 014 015import java.io.*; 016 017import javax.servlet.*; 018 019/** 020 * ServletInputStream wrapper around a normal input stream with support for limiting input. 021 */ 022public final class BoundedServletInputStream extends ServletInputStream { 023 024 private final InputStream is; 025 private final ServletInputStream sis; 026 private long remain; 027 028 /** 029 * Wraps the specified input stream. 030 * 031 * @param is The input stream to wrap. 032 * @param max The maximum number of bytes to read from the stream. 033 */ 034 public BoundedServletInputStream(InputStream is, long max) { 035 this.is = is; 036 this.sis = null; 037 this.remain = max; 038 } 039 040 /** 041 * Wraps the specified input stream. 042 * 043 * @param sis The input stream to wrap. 044 * @param max The maximum number of bytes to read from the stream. 045 */ 046 public BoundedServletInputStream(ServletInputStream sis, long max) { 047 this.sis = sis; 048 this.is = sis; 049 this.remain = max; 050 } 051 052 /** 053 * Wraps the specified byte array. 054 * 055 * @param b The byte contents of the stream. 056 */ 057 public BoundedServletInputStream(byte[] b) { 058 this(new ByteArrayInputStream(b), Long.MAX_VALUE); 059 } 060 061 @Override /* InputStream */ 062 public final int read() throws IOException { 063 decrement(); 064 return is.read(); 065 } 066 067 @Override /* InputStream */ 068 public int read(byte[] b) throws IOException { 069 return read(b, 0, b.length); 070 } 071 072 @Override /* InputStream */ 073 public int read(final byte[] b, final int off, final int len) throws IOException { 074 long numBytes = Math.min(len, remain); 075 int r = is.read(b, off, (int) numBytes); 076 if (r == -1) 077 return -1; 078 decrement(numBytes); 079 return r; 080 } 081 082 @Override /* InputStream */ 083 public long skip(final long n) throws IOException { 084 long toSkip = Math.min(n, remain); 085 long r = is.skip(toSkip); 086 decrement(r); 087 return r; 088 } 089 090 @Override /* InputStream */ 091 public int available() throws IOException { 092 if (remain <= 0) 093 return 0; 094 return is.available(); 095 } 096 097 @Override /* InputStream */ 098 public synchronized void reset() throws IOException { 099 is.reset(); 100 } 101 102 @Override /* InputStream */ 103 public synchronized void mark(int limit) { 104 is.mark(limit); 105 } 106 107 @Override /* InputStream */ 108 public boolean markSupported() { 109 return is.markSupported(); 110 } 111 112 @Override /* InputStream */ 113 public final void close() throws IOException { 114 is.close(); 115 } 116 117 @Override /* ServletInputStream */ 118 public boolean isFinished() { 119 return sis == null ? false : sis.isFinished(); 120 } 121 122 @Override /* ServletInputStream */ 123 public boolean isReady() { 124 return sis == null ? true : sis.isReady(); 125 } 126 127 @Override /* ServletInputStream */ 128 public void setReadListener(ReadListener arg0) { 129 if (sis != null) 130 sis.setReadListener(arg0); 131 } 132 133 private void decrement() throws IOException { 134 remain--; 135 if (remain < 0) 136 throw new IOException("Input limit exceeded. See @RestResource(maxInput)."); 137 } 138 139 private void decrement(long count) throws IOException { 140 remain -= count; 141 if (remain < 0) 142 throw new IOException("Input limit exceeded. See @RestResource(maxInput)."); 143 } 144}