diff --git a/ml/src/main/scala/org/apache/spark/graphx2/util/collection/GraphXPrimitiveVector.scala b/ml/src/main/scala/org/apache/spark/graphx2/util/collection/GraphXPrimitiveVector.scala
deleted file mode 100644
index 559cda00..00000000
--- a/ml/src/main/scala/org/apache/spark/graphx2/util/collection/GraphXPrimitiveVector.scala
+++ /dev/null
@@ -1,81 +0,0 @@
-/*
- * 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.spark.graphx2.util.collection
-
-import scala.reflect.ClassTag
-
-/**
- * An append-only, non-threadsafe, array-backed vector that is optimized for primitive types.
- */
-class GraphXPrimitiveVector[@specialized(Long, Int, Double) V: ClassTag](initialSize: Int = 64) {
-  private var _numElements = 0
-  private var _array: Array[V] = _
-
-  // NB: This must be separate from the declaration, otherwise the specialized parent class
-  // will get its own array with the same initial size.
-  _array = new Array[V](initialSize)
-
-  def apply(index: Int): V = {
-    require(index < _numElements)
-    _array(index)
-  }
-
-  def +=(value: V): Unit = {
-    if (_numElements == _array.length) {
-      resize(_array.length * 2)
-    }
-    _array(_numElements) = value
-    _numElements += 1
-  }
-
-  def capacity: Int = _array.length
-
-  def length: Int = _numElements
-
-  def size: Int = _numElements
-
-  def iterator: Iterator[V] = new Iterator[V] {
-    var index = 0
-    override def hasNext: Boolean = index < _numElements
-    override def next(): V = {
-      if (!hasNext) {
-        throw new NoSuchElementException
-      }
-      val value = _array(index)
-      index += 1
-      value
-    }
-  }
-
-  /** Gets the underlying array backing this vector. */
-  def array: Array[V] = _array
-
-  /** Trims this vector so that the capacity is equal to the size. */
-  def trim(): GraphXPrimitiveVector[V] = resize(size)
-
-  /** Resizes the array, dropping elements if the total length decreases. */
-  def resize(newLength: Int): GraphXPrimitiveVector[V] = {
-    val newArray = new Array[V](newLength)
-    _array.copyToArray(newArray)
-    _array = newArray
-    if (newLength < _numElements) {
-      _numElements = newLength
-    }
-    this
-  }
-}