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1
16 package org.apache.commons.vfs.provider.http;
17
18 import org.apache.commons.httpclient.methods.GetMethod;
19 import org.apache.commons.vfs.FileSystemException;
20 import org.apache.commons.vfs.provider.AbstractRandomAccessContent;
21 import org.apache.commons.vfs.util.MonitorInputStream;
22 import org.apache.commons.vfs.util.RandomAccessMode;
23
24 import java.io.DataInputStream  ;
25 import java.io.FilterInputStream ;
26 import java.io.IOException ;
27 import java.io.InputStream ;
28 import java.net.HttpURLConnection ;
29
30 class HttpRandomAccesContent extends AbstractRandomAccessContent
31 {
32 private final HttpFileObject fileObject;
33 private final HttpFileSystem fileSystem;
34
35 protected long filePointer = 0;
36 private DataInputStream dis = null;
37 private MonitorInputStream mis = null;
38
39 HttpRandomAccesContent(final HttpFileObject fileObject, RandomAccessMode mode)
40 {
41 super(mode);
42
43 this.fileObject = fileObject;
44 fileSystem = (HttpFileSystem) this.fileObject.getFileSystem();
45 }
46
47 public long getFilePointer() throws IOException
48 {
49 return filePointer;
50 }
51
52 public void seek(long pos) throws IOException
53 {
54 if (pos == filePointer)
55 {
56 return;
58 }
59
60 if (pos < 0)
61 {
62 throw new FileSystemException("vfs.provider/random-access-invalid-position.error",
63 new Object []
64 {
65 new Long (pos)
66 });
67 }
68 if (dis != null)
69 {
70 close();
71 }
72
73 filePointer = pos;
74 }
75
76 private void createStream() throws IOException
77 {
78 if (dis != null)
79 {
80 return;
81 }
82
83 final GetMethod getMethod = new GetMethod();
84 fileObject.setupMethod(getMethod);
85 getMethod.setRequestHeader("Range", "bytes=" + filePointer + "-");
86 final int status = fileSystem.getClient().executeMethod(getMethod);
87 if (status != HttpURLConnection.HTTP_PARTIAL)
88 {
89 throw new FileSystemException("vfs.provider.http/get-range.error", new Object []
90 {
91 fileObject.getName(),
92 new Long (filePointer)
93 });
94 }
95
96 mis = new HttpFileObject.HttpInputStream(getMethod);
97 dis = new DataInputStream (new FilterInputStream (mis)
98 {
99 public int read() throws IOException
100 {
101 int ret = super.read();
102 if (ret > -1)
103 {
104 filePointer++;
105 }
106 return ret;
107 }
108
109 public int read(byte b[]) throws IOException
110 {
111 int ret = super.read(b);
112 if (ret > -1)
113 {
114 filePointer+=ret;
115 }
116 return ret;
117 }
118
119 public int read(byte b[], int off, int len) throws IOException
120 {
121 int ret = super.read(b, off, len);
122 if (ret > -1)
123 {
124 filePointer+=ret;
125 }
126 return ret;
127 }
128 });
129 }
130
131
132 public void close() throws IOException
133 {
134 if (dis != null)
135 {
136 dis.close();
137 dis = null;
138 mis = null;
139 }
140 }
141
142 public long length() throws IOException
143 {
144 return fileObject.getContent().getSize();
145 }
146
147 public byte readByte() throws IOException
148 {
149 createStream();
150 byte data = dis.readByte();
151 return data;
152 }
153
154 public char readChar() throws IOException
155 {
156 createStream();
157 char data = dis.readChar();
158 return data;
159 }
160
161 public double readDouble() throws IOException
162 {
163 createStream();
164 double data = dis.readDouble();
165 return data;
166 }
167
168 public float readFloat() throws IOException
169 {
170 createStream();
171 float data = dis.readFloat();
172 return data;
173 }
174
175 public int readInt() throws IOException
176 {
177 createStream();
178 int data = dis.readInt();
179 return data;
180 }
181
182 public int readUnsignedByte() throws IOException
183 {
184 createStream();
185 int data = dis.readUnsignedByte();
186 return data;
187 }
188
189 public int readUnsignedShort() throws IOException
190 {
191 createStream();
192 int data = dis.readUnsignedShort();
193 return data;
194 }
195
196 public long readLong() throws IOException
197 {
198 createStream();
199 long data = dis.readLong();
200 return data;
201 }
202
203 public short readShort() throws IOException
204 {
205 createStream();
206 short data = dis.readShort();
207 return data;
208 }
209
210 public boolean readBoolean() throws IOException
211 {
212 createStream();
213 boolean data = dis.readBoolean();
214 return data;
215 }
216
217 public int skipBytes(int n) throws IOException
218 {
219 createStream();
220 int data = dis.skipBytes(n);
221 return data;
222 }
223
224 public void readFully(byte b[]) throws IOException
225 {
226 createStream();
227 dis.readFully(b);
228 }
229
230 public void readFully(byte b[], int off, int len) throws IOException
231 {
232 createStream();
233 dis.readFully(b, off, len);
234 }
235
236 public String readUTF() throws IOException
237 {
238 createStream();
239 String data = dis.readUTF();
240 return data;
241 }
242
243 public InputStream getInputStream() throws IOException
244 {
245 createStream();
246 return dis;
247 }
248 } |
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