Examples with DatasetType co.cask.cdap.api.dataset.module.DatasetType used on opensource projects

Example 1 with DatasetType

use of co.cask.cdap.api.dataset.module.DatasetType in project cdap by caskdata.

the class SingleTypeModule method register.

@Override
public void register(DatasetDefinitionRegistry registry) {
    final Constructor ctor = findSuitableCtorOrFail(dataSetClass);
    DatasetType typeAnn = dataSetClass.getAnnotation(DatasetType.class);
    // default type name to dataset class name
    String typeName = typeAnn != null ? typeAnn.value() : dataSetClass.getName();
    // The ordering is important. It is the same order as the parameters
    final Map<String, DatasetDefinition> embeddedDefinitions = Maps.newLinkedHashMap();
    final Class<?>[] paramTypes = ctor.getParameterTypes();
    Annotation[][] paramAnns = ctor.getParameterAnnotations();
    // Gather all dataset name and type information for the @EmbeddedDataset parameters
    for (int i = 1; i < paramTypes.length; i++) {
        // Must have the EmbeddedDataset as it's the contract of the findSuitableCtorOrFail method
        EmbeddedDataset anno = Iterables.filter(Arrays.asList(paramAnns[i]), EmbeddedDataset.class).iterator().next();
        String type = anno.type();
        // default to dataset class name if dataset type name is not specified through the annotation
        if (EmbeddedDataset.DEFAULT_TYPE_NAME.equals(type)) {
            type = paramTypes[i].getName();
        }
        DatasetDefinition embeddedDefinition = registry.get(type);
        if (embeddedDefinition == null) {
            throw new IllegalStateException(String.format("Unknown Dataset type '%s', specified by parameter number %d of the %s Dataset", type, i, dataSetClass.getName()));
        }
        embeddedDefinitions.put(anno.value(), embeddedDefinition);
    }
    registry.add(new CompositeDatasetDefinition<Dataset>(typeName, embeddedDefinitions) {

        @Override
        public Dataset getDataset(DatasetContext datasetContext, DatasetSpecification spec, Map<String, String> arguments, ClassLoader classLoader) throws IOException {
            List<Object> params = new ArrayList<>();
            params.add(spec);
            for (Map.Entry<String, DatasetDefinition> entry : embeddedDefinitions.entrySet()) {
                params.add(entry.getValue().getDataset(datasetContext, spec.getSpecification(entry.getKey()), arguments, classLoader));
            }
            try {
                return (Dataset) ctor.newInstance(params.toArray());
            } catch (Exception e) {
                throw Throwables.propagate(e);
            }
        }
    });
}