char[] buf = new char[DEFAULT_BUF_SIZE];
    int nRead;
    long total = 0;
    while ((nRead = from.read(buf)) != -1) {
      to.write(buf, 0, nRead);
      total += nRead;
    }
    return total;
  }

  /**
   * Reads all characters from a {@link Readable} object into a {@link String}. Does not close the
   * {@code Readable}.
   *
   * @param r the object to read from

}

func (r *checksumReader) Read(b []byte) (n int, err error) {
	if r.err != nil {
		return 0, r.err
	}
	n, err = r.rc.Read(b)
	r.hash.Write(b[:n])
	r.nread += uint64(n)
	if r.nread > r.f.UncompressedSize64 {
		return 0, ErrFormat
	}
	if err == nil {
		return
	}
	if err == io.EOF {
		if r.nread != r.f.UncompressedSize64 {
			return 0, io.ErrUnexpectedEOF
		}

        while (!eol) {
            switch (c = read()) {
            case -1:
            case '\n':
                eol = true;
                break;
            case '\r':
                eol = true;
                final long cur = fp;
                if (read() != '\n') {
                    fp = cur;
                }
                break;
            default:
                input.append((char) c);

    /**
     * Reads exactly len bytes from the input stream into the buffer.
     *
     * @param in the input stream to read from
     * @param b the buffer to read into
     * @param off the offset in the buffer to start writing
     * @param len the number of bytes to read
     * @return the number of bytes actually read
     * @throws IOException if an I/O error occurs
     */

        b += 2 // We rewound two bytes and then added four.
        break
      } else {
        return null // Wrong delimiter.
      }
    }

    // Read a group, one to four hex digits.
    var value = 0
    groupOffset = i
    while (i < limit) {
      val hexDigit = input[i].parseHexDigit()
      if (hexDigit == -1) break
      value = (value shl 4) + hexDigit
      i++
    }

                try {
                    // Invalidate any cached read data
                    // This would typically clear file's internal read buffers
                    // For now, we log the action as the actual implementation
                    // depends on SmbFile's internal caching mechanism
                    log.info("Invalidated read cache for: {}", path);
                } catch (Exception e) {

    /**
     * Read bytes from the input stream into a buffer
     *
     * @param in the input stream to read from
     * @param b the buffer to read into
     * @param off the offset in the buffer to start writing
     * @param len the number of bytes to read
     * @return number of bytes read
     * @throws IOException if an I/O error occurs
     */

 *       block indefinitely or fail if the source creates an infinite reader.
 *   <li><b>Non-destructive:</b> A <i>destructive</i> reader will consume or otherwise alter the
 *       source as they are read from it. A source that provides such readers will not be reusable,
 *       and operations that read from the stream (including {@link #length()}, in some

 *       block indefinitely or fail if the source creates an infinite reader.
 *   <li><b>Non-destructive:</b> A <i>destructive</i> reader will consume or otherwise alter the
 *       source as they are read from it. A source that provides such readers will not be reusable,
 *       and operations that read from the stream (including {@link #length()}, in some

    }
    
    private void invalidateReadCache(String path) {
        // Implementation to invalidate read cache
        // This will be called when losing read cache
    }
}
```

## 5. Lease Break Handling

### 5.1 Lease Break Notification
```java
package jcifs.internal.smb2.lease;

import jcifs.internal.smb2.ServerMessageBlock2;