Feature/import documents batch threads

[rkhaja]

This pull request addresses enhancements requested in #273
Please review.

[hkernbach]

Hey @rkhaja, first of all, thank you very much for contributing. The code itself looks good to me. We need a JUnit test to test that feature, then we're able to merge.

If you could also add a test, it would be great. Otherwise, we will add one as soon as we can.

[rkhaja]

@hkernbach Thanks! I will of course write the JUnit test(s) (hopefully very soon) ... I wanted to be sure that the this code met your coding standards before I spent effort to write the tests.

[rkhaja]

I've added the following test:

	@Test
	public void importDocumentsBatchSizeNumThreads() {
		final Collection<BaseDocument> values = new ArrayList<BaseDocument>();
		for (int i = 1; i <= 100; i++) {
			values.add(new BaseDocument(String.valueOf(i)));
		}
		int batchSize = 5;
		int numThreads = 4;
		final Collection<DocumentImportEntity> docsList = db.collection(COLLECTION_NAME).importDocuments(values,
				new DocumentImportOptions(), batchSize, numThreads);
                assertThat(docsList.size(), is(values.size() / batchSize));
		for (final DocumentImportEntity docs : docsList) {
			assertThat(docs, is(notNullValue()));
			assertThat(docs.getCreated(), is(batchSize));
			assertThat(docs.getEmpty(), is(0));
			assertThat(docs.getErrors(), is(0));
			assertThat(docs.getIgnored(), is(0));
			assertThat(docs.getUpdated(), is(0));
			assertThat(docs.getDetails(), is(empty()));
		}
	}

Essentially it is a copy of the basic importDocuments() test except that iterates through individual DocumentImportEntity objects.

	@Test
	public void importDocuments() {
		final Collection<BaseDocument> values = new ArrayList<BaseDocument>();
		values.add(new BaseDocument());
		values.add(new BaseDocument());
		values.add(new BaseDocument());
		final DocumentImportEntity docs = db.collection(COLLECTION_NAME).importDocuments(values);
		assertThat(docs, is(notNullValue()));
		assertThat(docs.getCreated(), is(values.size()));
		assertThat(docs.getEmpty(), is(0));
		assertThat(docs.getErrors(), is(0));
		assertThat(docs.getIgnored(), is(0));
		assertThat(docs.getUpdated(), is(0));
		assertThat(docs.getDetails(), is(empty()));
	}

I hope the test is sufficient but if it is not please let me know.

[hkernbach]

LGTM

[hkernbach]

Thank you for contributing, will merge your PR now. This will be then part of our next ArangoDB Java Driver release (Version: 5.0.8).

[rkhaja]

Thank you!

[rkhaja]

@hkernbach I noticed a small problem.
RIght before the return statement on this line
we need to shutdown the executorService.

        executorService.shutdown();

If another pull request is needed, please let me know.

[hkernbach]

Will fix that, thanks for spotting :)