public int read(byte[] buffer, int pos, int len) throws IOException {
if (transparent) {
return (input.read(buffer, pos, len));
}
// [header]
// file [body-start -> body-end]
long start_pos = seek_position;
int start_len = len;
if (seek_position < header.length) {
int rem = (int) (header.length - seek_position);
if (rem > len) {
rem = len;
}
System.arraycopy(header, (int) seek_position, buffer, pos, rem);
pos += rem;
len -= rem;
seek_position += rem;
}
if (len > 0) {
long file_position = body_start + seek_position - header.length;
long rem = body_end - file_position;
if (len < rem) {
rem = len;
}
input.seek(file_position);
int temp = input.read(buffer, pos, (int) rem);
pos += temp;
len -= temp;
seek_position += temp;
}
int read = start_len - len;
seek_position = start_pos + read;
return (read);
}
