public void seek(long pos) throws IOException {
        if (pos < 0) {
            throw new IOException(PropertyUtil.getString("MemoryCacheSeekableStream0"));
        }
        pointer = pos;
    }
Sets the file-pointer offset, measured from the beginning of this
file, at which the next read occurs.

@param      pos   the offset position, measured in bytes from the
                  beginning of the file, at which to set the file
                  pointer.
@exception  IOException  if <code>pos</code> is less than
                         <code>0</code> or if an I/O error occurs.
plugins/svg-plugin/batik-codec-fix/src/main/java/org/apache/batik/ext/awt/image/codec/util/MemoryCacheSeekableStream.java