minor adjustments for performance (#16714)

changes:
* switch to stop using some string.format
* switch some streams to classic loops

processing/src/main/java/org/apache/druid/query/groupby/epinephelinae/GroupByQueryEngine.java

@@ -211,24 +211,25 @@ public class GroupByQueryEngine
       final List<DimensionSpec> dimensions
   )
   {
-    return dimensions
+    for (DimensionSpec dimension : dimensions) {
-        .stream()
-        .allMatch(
-            dimension -> {
       if (dimension.mustDecorate()) {
         // DimensionSpecs that decorate may turn singly-valued columns into multi-valued selectors.
         // To be safe, we must return false here.
         return false;
       }
 
+      // if dimension spec type is array, skip it since we can handle array or multi-valued
+      if (dimension.getOutputType().isArray()) {
+        continue;
+      }
+
       // Now check column capabilities, which must be present and explicitly not multi-valued and not arrays
-              final ColumnCapabilities columnCapabilities = inspector.getColumnCapabilities(dimension.getDimension());
+      final ColumnCapabilities capabilities = inspector.getColumnCapabilities(dimension.getDimension());
-              return dimension.getOutputType().isArray()
+      if (capabilities == null || capabilities.hasMultipleValues().isMaybeTrue() || capabilities.isArray()) {
-                     || (columnCapabilities != null
+        return false;
-                         && columnCapabilities.hasMultipleValues().isFalse()
+      }
-                         && !columnCapabilities.isArray()
+    }
-                     );
+    return true;
-            });
   }
 
   private abstract static class GroupByEngineIterator<KeyType> implements Iterator<ResultRow>, Closeable

processing/src/main/java/org/apache/druid/query/groupby/epinephelinae/vector/VectorGroupByEngine.java

@@ -29,6 +29,7 @@ import org.apache.druid.java.util.common.io.Closer;
 import org.apache.druid.java.util.common.parsers.CloseableIterator;
 import org.apache.druid.query.DruidProcessingConfig;
 import org.apache.druid.query.aggregation.AggregatorAdapters;
+import org.apache.druid.query.aggregation.AggregatorFactory;
 import org.apache.druid.query.dimension.DefaultDimensionSpec;
 import org.apache.druid.query.dimension.DimensionSpec;
 import org.apache.druid.query.filter.Filter;
@@ -204,9 +205,7 @@ public class VectorGroupByEngine
     return adapter.canVectorize(filter, query.getVirtualColumns(), false)
            && canVectorizeDimensions(inspector, query.getDimensions())
            && VirtualColumns.shouldVectorize(query, query.getVirtualColumns(), adapter)
-           && query.getAggregatorSpecs()
+           && canVectorizeAggregators(inspector, query.getAggregatorSpecs());
-                   .stream()
-                   .allMatch(aggregatorFactory -> aggregatorFactory.canVectorize(inspector));
   }
 
   private static boolean canVectorizeDimensions(
@@ -214,10 +213,7 @@ public class VectorGroupByEngine
       final List<DimensionSpec> dimensions
   )
   {
-    return dimensions
+    for (DimensionSpec dimension : dimensions) {
-        .stream()
-        .allMatch(
-            dimension -> {
       if (!dimension.canVectorize()) {
         return false;
       }
@@ -236,13 +232,26 @@ public class VectorGroupByEngine
 
       // Now check column capabilities.
       final ColumnCapabilities columnCapabilities = inspector.getColumnCapabilities(dimension.getDimension());
+      if (columnCapabilities != null && columnCapabilities.hasMultipleValues().isMaybeTrue()) {
         // null here currently means the column does not exist, nil columns can be vectorized
-              if (columnCapabilities == null) {
+        // multi-value columns implicit unnest is not currently supported in the vector processing engine
+        return false;
+      }
+    }
     return true;
   }
-              // must be single valued
+
-              return columnCapabilities.hasMultipleValues().isFalse();
+  public static boolean canVectorizeAggregators(
-            });
+      final ColumnInspector inspector,
+      final List<AggregatorFactory> aggregatorFactories
+  )
+  {
+    for (AggregatorFactory aggregatorFactory : aggregatorFactories) {
+      if (!aggregatorFactory.canVectorize(inspector)) {
+        return false;
+      }
+    }
+    return true;
   }
 
   @VisibleForTesting

processing/src/main/java/org/apache/druid/query/timeseries/TimeseriesQueryEngine.java

@@ -37,6 +37,7 @@ import org.apache.druid.query.aggregation.Aggregator;
 import org.apache.druid.query.aggregation.AggregatorAdapters;
 import org.apache.druid.query.aggregation.AggregatorFactory;
 import org.apache.druid.query.filter.Filter;
+import org.apache.druid.query.groupby.epinephelinae.vector.VectorGroupByEngine;
 import org.apache.druid.query.vector.VectorCursorGranularizer;
 import org.apache.druid.segment.ColumnInspector;
 import org.apache.druid.segment.SegmentMissingException;
@@ -103,7 +104,7 @@ public class TimeseriesQueryEngine
     final boolean doVectorize = query.context().getVectorize().shouldVectorize(
         adapter.canVectorize(filter, query.getVirtualColumns(), descending)
         && VirtualColumns.shouldVectorize(query, query.getVirtualColumns(), adapter)
-        && query.getAggregatorSpecs().stream().allMatch(aggregatorFactory -> aggregatorFactory.canVectorize(inspector))
+        && VectorGroupByEngine.canVectorizeAggregators(inspector, query.getAggregatorSpecs())
     );
 
     final Sequence<Result<TimeseriesResultValue>> result;

processing/src/main/java/org/apache/druid/segment/VirtualColumns.java

@@ -266,7 +266,12 @@ public class VirtualColumns implements Cacheable
   public boolean canVectorize(ColumnInspector columnInspector)
   {
     final ColumnInspector inspector = wrapInspector(columnInspector);
-    return virtualColumns.stream().allMatch(virtualColumn -> virtualColumn.canVectorize(inspector));
+    for (VirtualColumn virtualColumn : virtualColumns) {
+      if (!virtualColumn.canVectorize(inspector)) {
+        return false;
+      }
+    }
+    return true;
   }
 
   /**

processing/src/main/java/org/apache/druid/segment/nested/CompressedNestedDataComplexColumn.java

@@ -25,6 +25,7 @@ import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Sets;
 import com.google.common.primitives.Doubles;
 import org.apache.druid.collections.bitmap.ImmutableBitmap;
+import org.apache.druid.error.DruidException;
 import org.apache.druid.java.util.common.IAE;
 import org.apache.druid.java.util.common.ISE;
 import org.apache.druid.java.util.common.RE;
@@ -915,13 +916,11 @@ public abstract class CompressedNestedDataComplexColumn<TStringDictionary extend
       );
       // we should check this someday soon, but for now just read it to push the buffer position ahead
       int flags = dataBuffer.getInt();
-      Preconditions.checkState(
+      if (flags != DictionaryEncodedColumnPartSerde.NO_FLAGS) {
-          flags == DictionaryEncodedColumnPartSerde.NO_FLAGS,
+        throw DruidException.defensive(
-          StringUtils.format(
+            "Unrecognized bits set in space reserved for future flags for field column [%s]", field
-              "Unrecognized bits set in space reserved for future flags for field column [%s]",
-              field
-          )
         );
+      }
 
       final Supplier<FixedIndexed<Integer>> localDictionarySupplier = FixedIndexed.read(
           dataBuffer,

processing/src/main/java/org/apache/druid/segment/nested/NestedCommonFormatColumnSerializer.java

@@ -123,6 +123,6 @@ public abstract class NestedCommonFormatColumnSerializer implements GenericColum
    */
   public static String getInternalFileName(String fileNameBase, String field)
   {
-    return StringUtils.format("%s.%s", fileNameBase, field);
+    return fileNameBase + "." + field;
   }
 }

processing/src/main/java/org/apache/druid/segment/nested/NestedDataColumnSerializerV4.java

@@ -27,7 +27,6 @@ import org.apache.druid.common.config.NullHandling;
 import org.apache.druid.java.util.common.FileUtils;
 import org.apache.druid.java.util.common.ISE;
 import org.apache.druid.java.util.common.RE;
-import org.apache.druid.java.util.common.StringUtils;
 import org.apache.druid.java.util.common.io.Closer;
 import org.apache.druid.java.util.common.io.smoosh.FileSmoosher;
 import org.apache.druid.java.util.common.io.smoosh.SmooshedWriter;
@@ -182,7 +181,7 @@ public class NestedDataColumnSerializerV4 implements GenericColumnSerializer<Str
     doubleDictionaryWriter.open();
 
     rawWriter = new CompressedVariableSizedBlobColumnSerializer(
-        getInternalFileName(name, RAW_FILE_NAME),
+        NestedCommonFormatColumnSerializer.getInternalFileName(name, RAW_FILE_NAME),
         segmentWriteOutMedium,
         indexSpec.getJsonCompression() != null ? indexSpec.getJsonCompression() : CompressionStrategy.LZ4
     );
@@ -390,14 +389,9 @@ public class NestedDataColumnSerializerV4 implements GenericColumnSerializer<Str
 
   private void writeInternal(FileSmoosher smoosher, Serializer serializer, String fileName) throws IOException
   {
-    final String internalName = getInternalFileName(name, fileName);
+    final String internalName = NestedCommonFormatColumnSerializer.getInternalFileName(name, fileName);
     try (SmooshedWriter smooshChannel = smoosher.addWithSmooshedWriter(internalName, serializer.getSerializedSize())) {
       serializer.writeTo(smooshChannel, smoosher);
     }
   }
-
-  public static String getInternalFileName(String fileNameBase, String field)
-  {
-    return StringUtils.format("%s.%s", fileNameBase, field);
-  }
 }