34 * This class implements a stream filter for uncompressing data in the 35 * "deflate" compression format. It is also used as the basis for other 36 * decompression filters, such as GZIPInputStream. 37 * 38 * @see Inflater 39 * @author David Connelly 40 */ 41 public 42 class InflaterInputStream extends FilterInputStream { 43 /** 44 * Decompressor for this stream. 45 */ 46 protected Inflater inf; 47 48 /** 49 * Input buffer for decompression. 50 */ 51 protected byte[] buf; 52 53 /** 54 * Length of input buffer. 55 */ 56 protected int len; 57 58 private boolean closed = false; 59 // this flag is set to true after EOF has reached 60 private boolean reachEOF = false; 61 62 /** 63 * Check to make sure that this stream has not been closed 64 */ 65 private void ensureOpen() throws IOException { 66 if (closed) { 67 throw new IOException("Stream closed"); 68 } 69 } 70 71 72 /** 73 * Creates a new input stream with the specified decompressor and 74 * buffer size. 75 * @param in the input stream 76 * @param inf the decompressor ("inflater") 77 * @param size the input buffer size 78 * @exception IllegalArgumentException if {@code size <= 0} 79 */ 80 public InflaterInputStream(InputStream in, Inflater inf, int size) { 81 super(in); 82 if (in == null || inf == null) { 83 throw new NullPointerException(); 84 } else if (size <= 0) { 85 throw new IllegalArgumentException("buffer size <= 0"); 86 } 87 this.inf = inf; 88 buf = new byte[size]; 89 } 90 91 /** 92 * Creates a new input stream with the specified decompressor and a 93 * default buffer size. 94 * @param in the input stream 95 * @param inf the decompressor ("inflater") 96 */ 97 public InflaterInputStream(InputStream in, Inflater inf) { 98 this(in, inf, 512); 99 } 100 101 boolean usesDefaultInflater = false; 102 103 /** 104 * Creates a new input stream with a default decompressor and buffer size. 105 * @param in the input stream 106 */ 107 public InflaterInputStream(InputStream in) { 108 this(in, new Inflater()); 222 */ 223 public void close() throws IOException { 224 if (!closed) { 225 if (usesDefaultInflater) 226 inf.end(); 227 in.close(); 228 closed = true; 229 } 230 } 231 232 /** 233 * Fills input buffer with more data to decompress. 234 * @exception IOException if an I/O error has occurred 235 */ 236 protected void fill() throws IOException { 237 ensureOpen(); 238 len = in.read(buf, 0, buf.length); 239 if (len == -1) { 240 throw new EOFException("Unexpected end of ZLIB input stream"); 241 } 242 inf.setInput(buf, 0, len); 243 } 244 245 /** 246 * Tests if this input stream supports the <code>mark</code> and 247 * <code>reset</code> methods. The <code>markSupported</code> 248 * method of <code>InflaterInputStream</code> returns 249 * <code>false</code>. 250 * 251 * @return a <code>boolean</code> indicating if this stream type supports 252 * the <code>mark</code> and <code>reset</code> methods. 253 * @see java.io.InputStream#mark(int) 254 * @see java.io.InputStream#reset() 255 */ 256 public boolean markSupported() { 257 return false; 258 } 259 260 /** 261 * Marks the current position in this input stream. 267 * the mark position becomes invalid. 268 * @see java.io.InputStream#reset() 269 */ 270 public synchronized void mark(int readlimit) { 271 } 272 273 /** 274 * Repositions this stream to the position at the time the 275 * <code>mark</code> method was last called on this input stream. 276 * 277 * <p> The method <code>reset</code> for class 278 * <code>InflaterInputStream</code> does nothing except throw an 279 * <code>IOException</code>. 280 * 281 * @exception IOException if this method is invoked. 282 * @see java.io.InputStream#mark(int) 283 * @see java.io.IOException 284 */ 285 public synchronized void reset() throws IOException { 286 throw new IOException("mark/reset not supported"); 287 } 288 } | 34 * This class implements a stream filter for uncompressing data in the 35 * "deflate" compression format. It is also used as the basis for other 36 * decompression filters, such as GZIPInputStream. 37 * 38 * @see Inflater 39 * @author David Connelly 40 */ 41 public 42 class InflaterInputStream extends FilterInputStream { 43 /** 44 * Decompressor for this stream. 45 */ 46 protected Inflater inf; 47 48 /** 49 * Input buffer for decompression. 50 */ 51 protected byte[] buf; 52 53 /** 54 * Original input buffer. 55 */ 56 protected byte[] originBuf; 57 58 /** 59 * Length of input buffer. 60 */ 61 protected int len; 62 63 private boolean closed = false; 64 // this flag is set to true after EOF has reached 65 private boolean reachEOF = false; 66 67 private ZipCryption zipCryption; 68 69 /** 70 * Check to make sure that this stream has not been closed 71 */ 72 private void ensureOpen() throws IOException { 73 if (closed) { 74 throw new IOException("Stream closed"); 75 } 76 } 77 78 79 /** 80 * Creates a new input stream with the specified decompressor and 81 * buffer size. 82 * @param in the input stream 83 * @param inf the decompressor ("inflater") 84 * @param size the input buffer size 85 * @exception IllegalArgumentException if {@code size <= 0} 86 */ 87 public InflaterInputStream(InputStream in, Inflater inf, int size) { 88 super(in); 89 if (in == null || inf == null) { 90 throw new NullPointerException(); 91 } else if (size <= 0) { 92 throw new IllegalArgumentException("buffer size <= 0"); 93 } 94 this.inf = inf; 95 buf = new byte[size]; 96 originBuf = new byte[size]; 97 } 98 99 /** 100 * Creates a new input stream with the specified decompressor and a 101 * default buffer size. 102 * @param in the input stream 103 * @param inf the decompressor ("inflater") 104 */ 105 public InflaterInputStream(InputStream in, Inflater inf) { 106 this(in, inf, 512); 107 } 108 109 boolean usesDefaultInflater = false; 110 111 /** 112 * Creates a new input stream with a default decompressor and buffer size. 113 * @param in the input stream 114 */ 115 public InflaterInputStream(InputStream in) { 116 this(in, new Inflater()); 230 */ 231 public void close() throws IOException { 232 if (!closed) { 233 if (usesDefaultInflater) 234 inf.end(); 235 in.close(); 236 closed = true; 237 } 238 } 239 240 /** 241 * Fills input buffer with more data to decompress. 242 * @exception IOException if an I/O error has occurred 243 */ 244 protected void fill() throws IOException { 245 ensureOpen(); 246 len = in.read(buf, 0, buf.length); 247 if (len == -1) { 248 throw new EOFException("Unexpected end of ZLIB input stream"); 249 } 250 251 if (zipCryption != null) { 252 System.arraycopy(buf, 0, originBuf, 0, len); 253 zipCryption.decryptBytes(buf, 0, len); 254 } 255 256 inf.setInput(buf, 0, len); 257 } 258 259 /** 260 * Tests if this input stream supports the <code>mark</code> and 261 * <code>reset</code> methods. The <code>markSupported</code> 262 * method of <code>InflaterInputStream</code> returns 263 * <code>false</code>. 264 * 265 * @return a <code>boolean</code> indicating if this stream type supports 266 * the <code>mark</code> and <code>reset</code> methods. 267 * @see java.io.InputStream#mark(int) 268 * @see java.io.InputStream#reset() 269 */ 270 public boolean markSupported() { 271 return false; 272 } 273 274 /** 275 * Marks the current position in this input stream. 281 * the mark position becomes invalid. 282 * @see java.io.InputStream#reset() 283 */ 284 public synchronized void mark(int readlimit) { 285 } 286 287 /** 288 * Repositions this stream to the position at the time the 289 * <code>mark</code> method was last called on this input stream. 290 * 291 * <p> The method <code>reset</code> for class 292 * <code>InflaterInputStream</code> does nothing except throw an 293 * <code>IOException</code>. 294 * 295 * @exception IOException if this method is invoked. 296 * @see java.io.InputStream#mark(int) 297 * @see java.io.IOException 298 */ 299 public synchronized void reset() throws IOException { 300 throw new IOException("mark/reset not supported"); 301 } 302 303 /** 304 * Set ZIP encryption/decryption engine to this inflater. 305 * @param zipCryption ZIP encrypt/decrypt engine. 306 */ 307 public void setZipCryption(ZipCryption zipCryption) { 308 this.zipCryption = zipCryption; 309 } 310 } |