Java tutorial
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See the License for the * specific language governing permissions and limitations * under the License. */ package org.apache.druid.segment; import com.google.common.base.Function; import com.google.common.base.Preconditions; import com.google.common.base.Throwables; import com.google.common.collect.Iterables; import com.google.common.collect.Lists; import org.apache.druid.data.input.InputRow; import org.apache.druid.java.util.common.StringUtils; import org.apache.druid.query.aggregation.AggregatorFactory; import org.apache.druid.query.aggregation.CountAggregatorFactory; import org.apache.druid.segment.incremental.IncrementalIndex; import org.apache.druid.segment.incremental.IncrementalIndexSchema; import org.apache.druid.segment.incremental.IndexSizeExceededException; import org.apache.druid.segment.writeout.OffHeapMemorySegmentWriteOutMediumFactory; import org.apache.druid.segment.writeout.SegmentWriteOutMediumFactory; import java.io.File; import java.io.IOException; import java.util.Arrays; import java.util.List; import java.util.UUID; import java.util.concurrent.ThreadLocalRandom; /** * Helps tests make segments. */ public class IndexBuilder { private static final int ROWS_PER_INDEX_FOR_MERGING = 1; private static final int DEFAULT_MAX_ROWS = Integer.MAX_VALUE; private IncrementalIndexSchema schema = new IncrementalIndexSchema.Builder() .withMetrics(new CountAggregatorFactory("count")).build(); private SegmentWriteOutMediumFactory segmentWriteOutMediumFactory = OffHeapMemorySegmentWriteOutMediumFactory .instance(); private IndexMerger indexMerger = TestHelper.getTestIndexMergerV9(segmentWriteOutMediumFactory); private File tmpDir; private IndexSpec indexSpec = new IndexSpec(); private int maxRows = DEFAULT_MAX_ROWS; private final List<InputRow> rows = Lists.newArrayList(); private IndexBuilder() { } public static IndexBuilder create() { return new IndexBuilder(); } public IndexBuilder schema(IncrementalIndexSchema schema) { this.schema = schema; return this; } public IndexBuilder segmentWriteOutMediumFactory(SegmentWriteOutMediumFactory segmentWriteOutMediumFactory) { this.segmentWriteOutMediumFactory = segmentWriteOutMediumFactory; this.indexMerger = TestHelper.getTestIndexMergerV9(segmentWriteOutMediumFactory); return this; } public IndexBuilder indexSpec(IndexSpec indexSpec) { this.indexSpec = indexSpec; return this; } public IndexBuilder tmpDir(File tmpDir) { this.tmpDir = tmpDir; return this; } public IndexBuilder rows(Iterable<InputRow> rows) { this.rows.clear(); Iterables.addAll(this.rows, rows); return this; } public IncrementalIndex buildIncrementalIndex() { return buildIncrementalIndexWithRows(schema, maxRows, rows); } public QueryableIndex buildMMappedIndex() { Preconditions.checkNotNull(indexMerger, "indexMerger"); Preconditions.checkNotNull(tmpDir, "tmpDir"); try (final IncrementalIndex incrementalIndex = buildIncrementalIndex()) { return TestHelper.getTestIndexIO() .loadIndex(indexMerger.persist(incrementalIndex, new File(tmpDir, StringUtils.format("testIndex-%s", ThreadLocalRandom.current().nextInt(Integer.MAX_VALUE))), indexSpec, null)); } catch (IOException e) { throw Throwables.propagate(e); } } public QueryableIndex buildMMappedMergedIndex() { IndexMerger indexMerger = TestHelper.getTestIndexMergerV9(segmentWriteOutMediumFactory); Preconditions.checkNotNull(tmpDir, "tmpDir"); final List<QueryableIndex> persisted = Lists.newArrayList(); try { for (int i = 0; i < rows.size(); i += ROWS_PER_INDEX_FOR_MERGING) { persisted .add(TestHelper.getTestIndexIO() .loadIndex( indexMerger.persist( buildIncrementalIndexWithRows(schema, maxRows, rows.subList(i, Math.min(rows.size(), i + ROWS_PER_INDEX_FOR_MERGING))), new File(tmpDir, StringUtils.format("testIndex-%s", UUID.randomUUID().toString())), indexSpec, null))); } final QueryableIndex merged = TestHelper.getTestIndexIO().loadIndex( indexMerger.merge(Lists.transform(persisted, new Function<QueryableIndex, IndexableAdapter>() { @Override public IndexableAdapter apply(QueryableIndex input) { return new QueryableIndexIndexableAdapter(input); } }), true, Iterables.toArray(Iterables.transform(Arrays.asList(schema.getMetrics()), new Function<AggregatorFactory, AggregatorFactory>() { @Override public AggregatorFactory apply(AggregatorFactory input) { return input.getCombiningFactory(); } }), AggregatorFactory.class), new File(tmpDir, StringUtils.format("testIndex-%s", UUID.randomUUID())), indexSpec)); for (QueryableIndex index : persisted) { index.close(); } return merged; } catch (IOException e) { throw Throwables.propagate(e); } } private static IncrementalIndex buildIncrementalIndexWithRows(IncrementalIndexSchema schema, int maxRows, Iterable<InputRow> rows) { Preconditions.checkNotNull(schema, "schema"); final IncrementalIndex incrementalIndex = new IncrementalIndex.Builder().setIndexSchema(schema) .setMaxRowCount(maxRows).buildOnheap(); for (InputRow row : rows) { try { incrementalIndex.add(row); } catch (IndexSizeExceededException e) { throw Throwables.propagate(e); } } return incrementalIndex; } }