Method openIterator

src/org/apache/pig/PigServer.java:989–1022

Executes a Pig Latin script up to and including indicated alias. That is, if a user does: PigServer server = new PigServer(); server.registerQuery("A = load 'foo';"); server.registerQuery("B = filter A by $0 > 0;"); server.registerQuery("C = order B by $1;"); Then server.openI

(String id)

     * @throws IOException
     */
    public Iterator<Tuple> openIterator(String id) throws IOException {
        try {
            pigContext.getProperties().setProperty( PigContext.JOB_NAME, jobName );
            if( jobPriority != null ) {
                pigContext.getProperties().setProperty( PigContext.JOB_PRIORITY, jobPriority );
            }
            ExecJob job = store(id, FileLocalizer.getTemporaryPath(pigContext)
                    .toString(), Utils.getTmpFileCompressorName(pigContext)
                    + "()");

            // invocation of "execute" is synchronous!

            if (job.getStatus() == JOB_STATUS.COMPLETED) {
                return job.getResults();
            } else if (job.getStatus() == JOB_STATUS.FAILED
                    && job.getException() != null) {
                // throw the backend exception in the failed case
                Exception e = job.getException();
                int errCode = 1066;
                String msg = "Unable to open iterator for alias " + id
                        + ". Backend error : " + e.getMessage();
                throw new FrontendException(msg, errCode, PigException.INPUT, e);
            } else {
                throw new IOException("Job terminated with anomalous status "
                        + job.getStatus().toString());
            }
        } catch (FrontendException e) {
            throw e;
        } catch (Exception e) {
            int errCode = 1066;
            String msg = "Unable to open iterator for alias " + id;
            throw new FrontendException(msg, errCode, PigException.INPUT, e);
        }
    }

    /**
     * Executes a Pig Latin script up to and including indicated alias and stores the resulting