src/share/classes/java/util/zip/CheckedInputStream.java

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  69      * bytes are read and <code>0</code> is returned.
  70      * @param buf the buffer into which the data is read
  71      * @param off the start offset in the destination array <code>b</code>
  72      * @param len the maximum number of bytes read
  73      * @return    the actual number of bytes read, or -1 if the end
  74      *            of the stream is reached.
  75      * @exception  NullPointerException If <code>buf</code> is <code>null</code>.
  76      * @exception  IndexOutOfBoundsException If <code>off</code> is negative,
  77      * <code>len</code> is negative, or <code>len</code> is greater than
  78      * <code>buf.length - off</code>
  79      * @exception IOException if an I/O error has occurred
  80      */
  81     public int read(byte[] buf, int off, int len) throws IOException {
  82         len = in.read(buf, off, len);
  83         if (len != -1) {
  84             cksum.update(buf, off, len);
  85         }
  86         return len;
  87     }
  88 


  89     /**
  90      * Skips specified number of bytes of input.
  91      * @param n the number of bytes to skip
  92      * @return the actual number of bytes skipped
  93      * @exception IOException if an I/O error has occurred
  94      */
  95     public long skip(long n) throws IOException {
  96         byte[] buf = new byte[512];


  97         long total = 0;
  98         while (total < n) {
  99             long len = n - total;
 100             len = read(buf, 0, len < buf.length ? (int)len : buf.length);
 101             if (len == -1) {
 102                 return total;
 103             }
 104             total += len;
 105         }
 106         return total;
 107     }
 108 
 109     /**
 110      * Returns the Checksum for this input stream.
 111      * @return the Checksum value
 112      */
 113     public Checksum getChecksum() {
 114         return cksum;
 115     }
 116 }


  69      * bytes are read and <code>0</code> is returned.
  70      * @param buf the buffer into which the data is read
  71      * @param off the start offset in the destination array <code>b</code>
  72      * @param len the maximum number of bytes read
  73      * @return    the actual number of bytes read, or -1 if the end
  74      *            of the stream is reached.
  75      * @exception  NullPointerException If <code>buf</code> is <code>null</code>.
  76      * @exception  IndexOutOfBoundsException If <code>off</code> is negative,
  77      * <code>len</code> is negative, or <code>len</code> is greater than
  78      * <code>buf.length - off</code>
  79      * @exception IOException if an I/O error has occurred
  80      */
  81     public int read(byte[] buf, int off, int len) throws IOException {
  82         len = in.read(buf, off, len);
  83         if (len != -1) {
  84             cksum.update(buf, off, len);
  85         }
  86         return len;
  87     }
  88 
  89     private byte[] tmpbuf;
  90 
  91     /**
  92      * Skips specified number of bytes of input.
  93      * @param n the number of bytes to skip
  94      * @return the actual number of bytes skipped
  95      * @exception IOException if an I/O error has occurred
  96      */
  97     public long skip(long n) throws IOException {
  98         if (tmpbuf == null) {
  99             tmpbuf = new byte[512];
 100         }
 101         long total = 0;
 102         while (total < n) {
 103             long len = n - total;
 104             len = read(buf, 0, len < tmpbuf.length ? (int)len : tmpbuf.length);
 105             if (len == -1) {
 106                 return total;
 107             }
 108             total += len;
 109         }
 110         return total;
 111     }
 112 
 113     /**
 114      * Returns the Checksum for this input stream.
 115      * @return the Checksum value
 116      */
 117     public Checksum getChecksum() {
 118         return cksum;
 119     }
 120 }