- * We consider that when the under-laying {@link InputStream} is also spent, - * we cannot have a next sub-stream (it will thus return FALSE). - *
* {@link IOException}s can happen when we have no data available in the * buffer; in that case, we fetch more data to know if we can have a next * sub-stream or not. + *
+ * This is can be a blocking call when data need to be fetched. * - * @return TRUE if we unblocked the next sub-stream, FALSE if not + * @return TRUE if we unblocked the next sub-stream, FALSE if not (i.e., + * FALSE when there are no more sub-streams to fetch) * * @throws IOException * in case of I/O error or if the stream is closed @@ -101,6 +103,8 @@ public class NextableInputStream extends BufferedInputStream { *
* That is, the next stream, if any, will be the last one and will not be * subject to the {@link NextableInputStreamStep}. + *
+ * This is can be a blocking call when data need to be fetched. * * @return TRUE if we unblocked the next sub-stream, FALSE if not * @@ -115,16 +119,19 @@ public class NextableInputStream extends BufferedInputStream { * Check if this stream is totally spent (no more data to read or to * process). *
- * Note: an empty stream that is still not started will return FALSE, as we - * don't know yet if it is empty. + * Note: when the stream is divided into sub-streams, each sub-stream will + * report its own eof when spent. * * @return TRUE if it is + * + * @throws IOException + * in case of I/O error */ @Override - public boolean eof() { + public boolean eof() throws IOException { return super.eof(); } - + /** * Check if we still have some data in the buffer and, if not, fetch some. * @@ -138,7 +145,7 @@ public class NextableInputStream extends BufferedInputStream { protected boolean preRead() throws IOException { if (!stopped) { boolean bufferChanged = super.preRead(); - checkBuffer(true); + checkBuffer(bufferChanged); return bufferChanged; } @@ -149,11 +156,6 @@ public class NextableInputStream extends BufferedInputStream { return false; } - /** - * We have more data available in the buffer or we can fetch more. - * - * @return TRUE if it is the case, FALSE if not - */ @Override protected boolean hasMoreData() { return started && super.hasMoreData(); @@ -172,12 +174,12 @@ public class NextableInputStream extends BufferedInputStream { * the {@link NextableInputStreamStep} */ private void checkBuffer(boolean newBuffer) { - if (step != null && stop > 0) { + if (step != null && stop >= 0) { if (newBuffer) { step.clearBuffer(); } - int stopAt = step.stop(buffer, start, stop); + int stopAt = step.stop(buffer, start, stop, eof); if (stopAt >= 0) { stop = stopAt; eof = true; @@ -189,12 +191,15 @@ public class NextableInputStream extends BufferedInputStream { /** * The implementation of {@link NextableInputStream#next()} and * {@link NextableInputStream#nextAll()}. + *
+ * This is can be a blocking call when data need to be fetched. * * @param all * TRUE for {@link NextableInputStream#nextAll()}, FALSE for * {@link NextableInputStream#next()} * - * @return TRUE if we unblocked the next sub-stream, FALSE if not + * @return TRUE if we unblocked the next sub-stream, FALSE if not (i.e., + * FALSE when there are no more sub-streams to fetch) * * @throws IOException * in case of I/O error or if the stream is closed @@ -213,23 +218,62 @@ public class NextableInputStream extends BufferedInputStream { return true; } - if (step != null && !hasMoreData() && stopped) { + // If started, must be stopped and no more data to continue + // i.e., sub-stream must be spent + if (!stopped || hasMoreData()) { + return false; + } + + if (step != null) { stop = step.getResumeLen(); start += step.getResumeSkip(); - eof = false; + eof = step.getResumeEof(); + stopped = false; if (all) { step = null; } - if (!preRead()) { - checkBuffer(false); - } + checkBuffer(false); - // consider that if EOF, there is no next - return hasMoreData(); + return true; } return false; + + // // consider that if EOF, there is no next + // if (start >= stop) { + // // Make sure, block if necessary + // preRead(); + // + // return hasMoreData(); + // } + // + // return true; + } + + /** + * Display a DEBUG {@link String} representation of this object. + *
+ * Do not use for release code. + */ + @Override + public String toString() { + String data = ""; + if (stop > 0) { + try { + data = new String(Arrays.copyOfRange(buffer, 0, stop), "UTF-8"); + } catch (UnsupportedEncodingException e) { + } + if (data.length() > 200) { + data = data.substring(0, 197) + "..."; + } + } + String rep = String.format( + "Nextable %s: %d -> %d [eof: %s] [more data: %s]: %s", + (stopped ? "stopped" : "running"), start, stop, "" + eof, "" + + hasMoreData(), data); + + return rep; } }