address java code

sql-plugin/src/main/java/com/nvidia/spark/rapids/GpuColumnVector.java

@@ -276,13 +276,8 @@ public static final class GpuArrowColumnarBatchBuilder extends GpuColumnarBatchB
     /**
      * A collection of builders for building up columnar data from Arrow data.
      * @param schema the schema of the batch.
-     * @param rows the maximum number of rows in this batch.
-     * @param batch if this is going to copy a ColumnarBatch in a non GPU format that batch
-     *              we are going to copy. If not this may be null. This is used to get an idea
-     *              of how big to allocate buffers that do not necessarily correspond to the
-     *              number of rows.
      */
-    public GpuArrowColumnarBatchBuilder(StructType schema, int rows, ColumnarBatch batch) {
+    public GpuArrowColumnarBatchBuilder(StructType schema) {
       fields = schema.fields();
       int len = fields.length;
       builders = new ai.rapids.cudf.ArrowColumnBuilder[len];
@@ -315,9 +310,9 @@ protected ColumnVector buildAndPutOnDevice(int builderIndex) {
       return gcv;
     }
 
-    public void copyColumnar(ColumnVector cv, int colNum, boolean nullable, int rows) {
+    public void copyColumnar(ColumnVector cv, int colNum, boolean ignored, int rows) {
       referenceHolders[colNum].addReferences(
-        HostColumnarToGpu.arrowColumnarCopy(cv, builder(colNum), nullable, rows)
+        HostColumnarToGpu.arrowColumnarCopy(cv, builder(colNum), rows)
       );
     }
 
@@ -345,12 +340,8 @@ public static final class GpuColumnarBatchBuilder extends GpuColumnarBatchBuilde
      * A collection of builders for building up columnar data.
      * @param schema the schema of the batch.
      * @param rows the maximum number of rows in this batch.
-     * @param batch if this is going to copy a ColumnarBatch in a non GPU format that batch
-     *              we are going to copy. If not this may be null. This is used to get an idea
-     *              of how big to allocate buffers that do not necessarily correspond to the
-     *              number of rows.
      */
-    public GpuColumnarBatchBuilder(StructType schema, int rows, ColumnarBatch batch) {
+    public GpuColumnarBatchBuilder(StructType schema, int rows) {
       fields = schema.fields();
       int len = fields.length;
       builders = new ai.rapids.cudf.HostColumnVector.ColumnBuilder[len];
@@ -423,7 +414,7 @@ public void close() {
   }
 
   private static final class ArrowBufReferenceHolder {
-    private List<ReferenceManager> references = new ArrayList<>();
+    private final List<ReferenceManager> references = new ArrayList<>();
 
     public void addReferences(List<ReferenceManager> refs) {
       references.addAll(refs);
@@ -495,7 +486,7 @@ public static DType getNonNestedRapidsType(DataType type) {
    * returning an empty batch from an operator is almost always the wrong thing to do.
    */
   public static ColumnarBatch emptyBatch(StructType schema) {
-    try (GpuColumnarBatchBuilder builder = new GpuColumnarBatchBuilder(schema, 0, null)) {
+    try (GpuColumnarBatchBuilder builder = new GpuColumnarBatchBuilder(schema, 0)) {
       return builder.build(0);
     }
   }
@@ -514,7 +505,7 @@ public static ColumnarBatch emptyBatch(List<Attribute> format) {
    * when serializing an empty broadcast table.
    */
   public static HostColumnVector[] emptyHostColumns(StructType schema) {
-    try (GpuColumnarBatchBuilder builder = new GpuColumnarBatchBuilder(schema, 0, null)) {
+    try (GpuColumnarBatchBuilder builder = new GpuColumnarBatchBuilder(schema, 0)) {
       return builder.buildHostColumns();
     }
   }
@@ -911,8 +902,8 @@ public static long getTotalDeviceMemoryUsed(ColumnarBatch batch) {
   public static long getTotalDeviceMemoryUsed(GpuColumnVector[] vectors) {
     long sum = 0;
     HashSet<Long> found = new HashSet<>();
-    for (int i = 0; i < vectors.length; i++) {
-      ai.rapids.cudf.ColumnVector cv = vectors[i].getBase();
+    for (GpuColumnVector vector : vectors) {
+      ai.rapids.cudf.ColumnVector cv = vector.getBase();
       long id = cv.getNativeView();
       if (found.add(id)) {
         sum += cv.getDeviceMemorySize();

sql-plugin/src/main/java/com/nvidia/spark/rapids/GpuColumnVectorBase.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020, NVIDIA CORPORATION.
+ * Copyright (c) 2020-2021, NVIDIA CORPORATION.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,7 +16,6 @@
 
 package com.nvidia.spark.rapids;
 
-import ai.rapids.cudf.DType;
 import org.apache.spark.sql.types.*;
 import org.apache.spark.sql.vectorized.ColumnVector;
 import org.apache.spark.sql.vectorized.ColumnarArray;

sql-plugin/src/main/java/com/nvidia/spark/rapids/RapidsHostColumnVector.java

@@ -1,6 +1,6 @@
 
 /*
- * Copyright (c) 2020, NVIDIA CORPORATION.
+ * Copyright (c) 2020-2021, NVIDIA CORPORATION.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -78,8 +78,4 @@ public final RapidsHostColumnVector incRefCount() {
   public final ai.rapids.cudf.HostColumnVector getBase() {
     return cudfCv;
   }
-
-  public GpuColumnVector copyToDevice() {
-    return new GpuColumnVector(type, cudfCv.copyToDevice());
-  }
 }

sql-plugin/src/main/java/com/nvidia/spark/rapids/RapidsHostColumnVectorCore.java

@@ -1,6 +1,6 @@
 
 /*
- * Copyright (c) 2020, NVIDIA CORPORATION.
+ * Copyright (c) 2020-2021, NVIDIA CORPORATION.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -31,9 +31,6 @@
 import org.apache.spark.sql.vectorized.ColumnarMap;
 import org.apache.spark.unsafe.types.UTF8String;
 
-import java.math.BigDecimal;
-import java.math.RoundingMode;
-
 /**
  * A GPU accelerated version of the Spark ColumnVector.
  * Most of the standard Spark APIs should never be called, as they assume that the data

sql-plugin/src/main/java/com/nvidia/spark/rapids/UnsafeRowToColumnarBatchIterator.java

@@ -145,7 +145,7 @@ public ColumnarBatch next() {
         devColumn = hostColumn.copyToDevice();
       }
     }
-    try (NvtxRange range = buildRange;
+    try (NvtxRange ignored = buildRange;
          ColumnVector cv = devColumn;
          Table tab = Table.convertFromRows(cv, rapidsTypes)) {
       return GpuColumnVector.from(tab, outputTypes);

udf-examples/src/main/java/com/nvidia/spark/rapids/udf/hive/URLEncode.java

@@ -77,7 +77,7 @@ public Object evaluate(GenericUDF.DeferredObject[] arguments) throws HiveExcepti
     if (text == null) {
       return null;
     }
-    String encoded = null;
+    String encoded;
     try {
       encoded = URLEncoder.encode(text.toString(), "utf-8")
           .replace("+", "%20")