001/* 002 * (C) Copyright 2011 Nuxeo SA (http://nuxeo.com/) and contributors. 003 * 004 * All rights reserved. This program and the accompanying materials 005 * are made available under the terms of the GNU Lesser General Public License 006 * (LGPL) version 2.1 which accompanies this distribution, and is available at 007 * http://www.gnu.org/licenses/lgpl.html 008 * 009 * This library is distributed in the hope that it will be useful, 010 * but WITHOUT ANY WARRANTY; without even the implied warranty of 011 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 012 * Lesser General Public License for more details. 013 * 014 * Contributors: 015 * matic 016 */ 017package org.nuxeo.ecm.automation.jaxrs.io; 018 019import java.io.BufferedInputStream; 020import java.io.File; 021import java.io.FileInputStream; 022import java.io.IOException; 023import java.io.InputStream; 024 025import javax.mail.internet.SharedInputStream; 026 027public class SharedFileInputStream extends InputStream implements SharedInputStream { 028 029 protected final InputStream in; 030 031 protected final SharedFileInputStream parent; 032 033 protected final File file; 034 035 protected final long length; 036 037 protected final long start; 038 039 protected long current; 040 041 protected long marked; 042 043 public SharedFileInputStream(File file) throws IOException { 044 this.in = new BufferedInputStream(new FileInputStream(file)); 045 this.parent = null; 046 this.file = file; 047 this.start = 0; 048 this.length = file.length(); 049 this.in.skip(start); 050 } 051 052 protected SharedFileInputStream(SharedFileInputStream parent, long start, long len) throws IOException { 053 this.in = new BufferedInputStream(new FileInputStream(parent.file)); 054 this.parent = parent; 055 this.file = parent.file; 056 this.start = start; 057 this.length = len; 058 this.in.skip(start); 059 } 060 061 public long getPosition() { 062 return this.current; 063 } 064 065 public SharedFileInputStream newStream(long start, long end) { 066 try { 067 long length; 068 if (end == -1L) { 069 length = this.length - start; 070 } else { 071 length = end - start; 072 } 073 return new SharedFileInputStream(this, this.start + start, length); 074 } catch (IOException localIOException) { 075 throw new IllegalStateException("unable to create shared stream: " + localIOException); 076 } 077 } 078 079 public int read(byte[] buffer) throws IOException { 080 return read(buffer, 0, buffer.length); 081 } 082 083 public int read(byte[] buffer, int offset, int len) throws IOException { 084 int i = 0; 085 if (len == 0) 086 return 0; 087 while (i < len) { 088 int j = read(); 089 if (j < 0) 090 break; 091 buffer[(offset + i)] = (byte) j; 092 ++i; 093 } 094 if (i == 0) 095 return -1; 096 return i; 097 } 098 099 public int read() throws IOException { 100 if (this.current == this.length) 101 return -1; 102 this.current += 1L; 103 return this.in.read(); 104 } 105 106 public boolean markSupported() { 107 return true; 108 } 109 110 public long skip(long len) throws IOException { 111 for (int count = 0; count < len; ++count) { 112 if (read() < 0) 113 return count; 114 } 115 return len; 116 } 117 118 public void mark(int limit) { 119 this.marked = this.current; 120 this.in.mark(limit); 121 } 122 123 public void reset() throws IOException { 124 current = marked; 125 in.reset(); 126 } 127 128 public SharedFileInputStream getRoot() { 129 if (parent != null) 130 return parent.getRoot(); 131 return this; 132 } 133}