[ARROW-7073][Java] Rewrite tests with vector populator and provide st…

…atic utility

java/vector/src/main/java/org/apache/arrow/vector/util/VectorAppender.java

@@ -37,7 +37,7 @@
 /**
  * Utility to append two vectors together.
  */
-public class VectorAppender implements VectorVisitor<ValueVector, Void> {
+class VectorAppender implements VectorVisitor<ValueVector, Void> {
 
   /**
    * The targetVector to be appended.
@@ -50,9 +50,9 @@ public class VectorAppender implements VectorVisitor<ValueVector, Void> {
    * Constructs a new targetVector appender, with the given targetVector.
    * @param targetVector the targetVector to be appended.
    */
-  public VectorAppender(ValueVector targetVector) {
+  VectorAppender(ValueVector targetVector) {
     this.targetVector = targetVector;
-    typeVisitor = new TypeEqualsVisitor(targetVector);
+    typeVisitor = new TypeEqualsVisitor(targetVector, false, true);
   }
 
   @Override
@@ -194,7 +194,7 @@ public ValueVector visit(FixedSizeListVector deltaVector, Void value) {
     int newValueCount = targetVector.getValueCount() + deltaVector.getValueCount();
 
     int targetListSize = targetListVector.getValueCount() * targetListVector.getListSize();
-    int deltaListSize = deltaVector.getValueCount() * deltaVector.getValueCount();
+    int deltaListSize = deltaVector.getValueCount() * deltaVector.getListSize();
 
     // make sure the underlying vector has value count set
     targetListVector.getDataVector().setValueCount(targetListSize);

java/vector/src/main/java/org/apache/arrow/vector/util/VectorBatchAppender.java

@@ -0,0 +1,39 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.arrow.vector.util;
+
+import org.apache.arrow.vector.ValueVector;
+
+/**
+ * Utility to add vector values in batch.
+ */
+public class VectorBatchAppender {
+
+  /**
+   * Add value vectors in batch.
+   * @param targetVector the  target vector.
+   * @param vectorsToAppend the vectors to append.
+   * @param <V> the vector type.
+   */
+  public static <V extends ValueVector> void batchAppend(V targetVector, V... vectorsToAppend) {
+    VectorAppender appender = new VectorAppender(targetVector);
+    for (V delta : vectorsToAppend) {
+      delta.accept(appender, null);
+    }
+  }
+}

java/vector/src/test/java/org/apache/arrow/vector/testing/ValueVectorDataPopulator.java

@@ -17,10 +17,14 @@
 
 package org.apache.arrow.vector.testing;
 
+import static org.junit.Assert.assertEquals;
+
 import java.nio.charset.StandardCharsets;
+import java.util.List;
 
 import org.apache.arrow.vector.BigIntVector;
 import org.apache.arrow.vector.BitVector;
+import org.apache.arrow.vector.BitVectorHelper;
 import org.apache.arrow.vector.DateDayVector;
 import org.apache.arrow.vector.DateMilliVector;
 import org.apache.arrow.vector.DecimalVector;
@@ -51,7 +55,12 @@
 import org.apache.arrow.vector.UInt8Vector;
 import org.apache.arrow.vector.VarBinaryVector;
 import org.apache.arrow.vector.VarCharVector;
+import org.apache.arrow.vector.complex.BaseRepeatedValueVector;
+import org.apache.arrow.vector.complex.FixedSizeListVector;
+import org.apache.arrow.vector.complex.ListVector;
 import org.apache.arrow.vector.holders.IntervalDayHolder;
+import org.apache.arrow.vector.types.Types;
+import org.apache.arrow.vector.types.pojo.FieldType;
 
 /**
  * Utility for populating {@link org.apache.arrow.vector.ValueVector}.
@@ -533,10 +542,62 @@ public static void setVector(VarCharVector vector, String... values) {
     vector.allocateNewSafe();
     for (int i = 0; i < length; i++) {
       if (values[i] != null) {
-        vector.set(i, values[i].getBytes(StandardCharsets.UTF_8));
+        vector.setSafe(i, values[i].getBytes(StandardCharsets.UTF_8));
       }
     }
     vector.setValueCount(length);
   }
 
+  /**
+   * Populate values for {@link ListVector}.
+   */
+  public static void setVector(ListVector vector, List<Integer>... values) {
+    Types.MinorType type = Types.MinorType.INT;
+    vector.addOrGetVector(FieldType.nullable(type.getType()));
+
+    IntVector dataVector = (IntVector) vector.getDataVector();
+    dataVector.allocateNew();
+
+    // set underlying vectors
+    int curPos = 0;
+    vector.getOffsetBuffer().setInt(0, curPos);
+    for (int i = 0; i < values.length; i++) {
+      BitVectorHelper.setBit(vector.getValidityBuffer(), i);
+      for (int value : values[i]) {
+        dataVector.set(curPos, value);
+        curPos += 1;
+      }
+      vector.getOffsetBuffer().setInt((i + 1) * BaseRepeatedValueVector.OFFSET_WIDTH, curPos);
+    }
+    dataVector.setValueCount(curPos);
+    vector.setLastSet(values.length - 1);
+    vector.setValueCount(values.length);
+  }
+
+  /**
+   * Populate values for {@link FixedSizeListVector}.
+   */
+  public static void setVector(FixedSizeListVector vector, List<Integer>... values) {
+    for (int i = 0; i < values.length; i++) {
+      assertEquals(vector.getListSize(), values[i].size());
+    }
+
+    Types.MinorType type = Types.MinorType.INT;
+    vector.addOrGetVector(FieldType.nullable(type.getType()));
+
+    IntVector dataVector = (IntVector) vector.getDataVector();
+    dataVector.allocateNew();
+
+    // set underlying vectors
+    int curPos = 0;
+    for (int i = 0; i < values.length; i++) {
+      BitVectorHelper.setBit(vector.getValidityBuffer(), i);
+      for (int value : values[i]) {
+        dataVector.set(curPos, value);
+        curPos += 1;
+      }
+    }
+    dataVector.setValueCount(curPos);
+    vector.setValueCount(values.length);
+  }
 }