ARROW-1719: [Java] Remove accessor and mutator interface

java/vector/src/main/codegen/templates/ComplexWriters.java

@@ -79,17 +79,17 @@ protected int idx() {
 
   public void write(${minor.class?cap_first}Holder h) {
     mutator.addSafe(idx(), h);
-    vector.getMutator().setValueCount(idx()+1);
+    vector.setValueCount(idx()+1);
   }
 
   public void write(${minor.class?cap_first}Holder h) {
     mutator.addSafe(idx(), h);
-    vector.getMutator().setValueCount(idx()+1);
+    vector.setValueCount(idx()+1);
   }
 
   public void write${minor.class}(<#list fields as field>${field.type} ${field.name}<#if field_has_next>, </#if></#list>) {
     mutator.addSafe(idx(), <#list fields as field>${field.name}<#if field_has_next>, </#if></#list>);
-    vector.getMutator().setValueCount(idx()+1);
+    vector.setValueCount(idx()+1);
   }
 
   public void setPosition(int idx) {

java/vector/src/main/codegen/templates/UnionVector.java

@@ -416,18 +416,6 @@ public void copyValueSafe(int from, int to) {
     }
   }
 
-  @Override
-  @Deprecated
-  public Accessor getAccessor() {
-    throw new UnsupportedOperationException("Accessor is not supported for reading from UNION");
-  }
-
-  @Override
-  @Deprecated
-  public Mutator getMutator() {
-    throw new UnsupportedOperationException("Mutator is not supported for writing to UNION");
-  }
-
   @Override
   public FieldReader getReader() {
     if (reader == null) {

java/vector/src/main/java/org/apache/arrow/vector/BaseDataValueVector.java

@@ -99,7 +99,7 @@ public ArrowBuf[] getBuffers(boolean clear) {
 
   @Override
   public int getBufferSize() {
-    if (getAccessor().getValueCount() == 0) {
+    if (getValueCount() == 0) {
       return 0;
     }
     return data.writerIndex();

java/vector/src/main/java/org/apache/arrow/vector/BaseFixedWidthVector.java

@@ -91,19 +91,6 @@ public BaseFixedWidthVector(final String name, final BufferAllocator allocator,
    * the top class as of now is not a good idea.
    */
 
-
-  @Override
-  @Deprecated
-  public Mutator getMutator() {
-    throw new UnsupportedOperationException("Mutator is not supported for writing to vector");
-  }
-
-  @Override
-  @Deprecated
-  public Accessor getAccessor() {
-    throw new UnsupportedOperationException("Accessor is not supported for reading from vector");
-  }
-
   /**
    * Get the memory address of buffer that manages the validity
    * (NULL or NON-NULL nature) of elements in the vector.
@@ -711,6 +698,7 @@ private void splitAndTransferValidityBuffer(int startIndex, int length,
    *
    * @return the number of null elements.
    */
+  @Override
   public int getNullCount() {
     return BitVectorHelper.getNullCount(validityBuffer, valueCount);
   }
@@ -721,6 +709,7 @@ public int getNullCount() {
    *
    * @return valueCount for the vector
    */
+  @Override
   public int getValueCount() {
     return valueCount;
   }
@@ -730,6 +719,7 @@ public int getValueCount() {
    *
    * @param valueCount  value count to set
    */
+  @Override
   public void setValueCount(int valueCount) {
     this.valueCount = valueCount;
     final int currentValueCapacity = getValueCapacity();
@@ -789,6 +779,7 @@ public boolean isSafe(int index) {
    * @param index  position of element
    * @return true if element at given index is null, false otherwise
    */
+  @Override
   public boolean isNull(int index) {
     return (isSet(index) == 0);
   }

java/vector/src/main/java/org/apache/arrow/vector/BaseValueVector.java

@@ -68,42 +68,6 @@ public TransferPair getTransferPair(BufferAllocator allocator) {
     return getTransferPair(name, allocator);
   }
 
-  public abstract static class BaseAccessor implements ValueVector.Accessor {
-    protected BaseAccessor() {
-    }
-
-    @Override
-    public boolean isNull(int index) {
-      return false;
-    }
-
-    @Override
-    // override this in case your implementation is faster, see BitVector
-    public int getNullCount() {
-      int nullCount = 0;
-      for (int i = 0; i < getValueCount(); i++) {
-        if (isNull(i)) {
-          nullCount++;
-        }
-      }
-      return nullCount;
-    }
-  }
-
-  public abstract static class BaseMutator implements ValueVector.Mutator {
-    protected BaseMutator() {
-    }
-
-    @Override
-    public void generateTestData(int values) {
-    }
-
-    //TODO: consider making mutator stateless(if possible) on another issue.
-    @Override
-    public void reset() {
-    }
-  }
-
   @Override
   public Iterator<ValueVector> iterator() {
     return Collections.emptyIterator();
@@ -136,33 +100,6 @@ protected ArrowBuf releaseBuffer(ArrowBuf buffer) {
     return buffer;
   }
 
-  @Override
-  public int getValueCount() {
-    return getAccessor().getValueCount();
-  }
-
-  @Override
-  public void setValueCount(int valueCount) {
-    getMutator().setValueCount(valueCount);
-  }
-
-  @Override
-
-  public Object getObject(int index) {
-    return getAccessor().getObject(index);
-  }
-
-  @Override
-
-  public int getNullCount() {
-    return getAccessor().getNullCount();
-  }
-
-  @Override
-  public boolean isNull(int index) {
-    return getAccessor().isNull(index);
-  }
-
   /* number of bytes for the validity buffer for the given valueCount */
   protected static int getValidityBufferSizeFromCount(final int valueCount) {
     return (int) Math.ceil(valueCount / 8.0);

java/vector/src/main/java/org/apache/arrow/vector/BaseVariableWidthVector.java

@@ -90,18 +90,6 @@ public BaseVariableWidthVector(final String name, final BufferAllocator allocato
    * the top class as of now is not a good idea.
    */
 
-  @Override
-  @Deprecated
-  public VariableWidthMutator getMutator() {
-    throw new UnsupportedOperationException("Mutator is not supported for writing into vector");
-  }
-
-  @Override
-  @Deprecated
-  public VariableWidthAccessor getAccessor() {
-    throw new UnsupportedOperationException("Accessor is not supported for reading from vector");
-  }
-
   /**
    * Get buffer that manages the validity (NULL or NON-NULL nature) of
    * elements in the vector. Consider it as a buffer for internal bit vector

java/vector/src/main/java/org/apache/arrow/vector/ValueVector.java

@@ -135,18 +135,6 @@ public interface ValueVector extends Closeable, Iterable<ValueVector> {
    */
   TransferPair makeTransferPair(ValueVector target);
 
-  /**
-   * @return an {@link org.apache.arrow.vector.ValueVector.Accessor accessor} that is used to read from this vector
-   * instance.
-   */
-  Accessor getAccessor();
-
-  /**
-   * @return an {@link org.apache.arrow.vector.ValueVector.Mutator mutator} that is used to write to this vector
-   * instance.
-   */
-  Mutator getMutator();
-
   /**
    * @return a {@link org.apache.arrow.vector.complex.reader.FieldReader field reader} that supports reading values
    * from this vector.
@@ -160,7 +148,7 @@ public interface ValueVector extends Closeable, Iterable<ValueVector> {
 
   /**
    * Returns the number of bytes that is used by this vector if it holds the given number
-   * of values. The result will be the same as if Mutator.setValueCount() were called, followed
+   * of values. The result will be the same as if setValueCount() were called, followed
    * by calling getBufferSize(), but without any of the closing side-effects that setValueCount()
    * implies wrt finishing off the population of a vector. Some operations might wish to use
    * this to determine how much memory has been used by a vector so far, even though it is
@@ -182,91 +170,56 @@ public interface ValueVector extends Closeable, Iterable<ValueVector> {
    */
   ArrowBuf[] getBuffers(boolean clear);
 
-  /**
-   * An abstraction that is used to read from this vector instance.
-   */
-  interface Accessor {
-    /**
-     * Get the Java Object representation of the element at the specified position. Useful for testing.
-     *
-     * @param index Index of the value to get
-     * @return the friendly java type
-     */
-    Object getObject(int index);
-
-    /**
-     * @return the number of values that is stored in this vector.
-     */
-    int getValueCount();
-
-    /**
-     * @param index the index to check for nullity
-     * @return true if the value at the given index is null, false otherwise.
-     */
-    boolean isNull(int index);
-
-    /**
-     * @return the number of null values
-     */
-    int getNullCount();
-  }
-
-  /**
-   * An abstraction that is used to write into this vector instance.
-   */
-  interface Mutator {
-    /**
-     * Sets the number of values that is stored in this vector to the given value count.
-     *
-     * @param valueCount value count to set.
-     */
-    void setValueCount(int valueCount);
-
-    /**
-     * Resets the mutator to pristine state.
-     */
-    void reset();
-
-    /**
-     * @param values the number of values to generate
-     * @deprecated this has nothing to do with value vector abstraction and should be removed.
-     */
-    @Deprecated
-    void generateTestData(int values);
-  }
-
   /**
    * Gets the underlying buffer associated with validity vector
    *
    * @return buffer
    */
-  public ArrowBuf getValidityBuffer();
+  ArrowBuf getValidityBuffer();
 
   /**
    * Gets the underlying buffer associated with data vector
    *
    * @return buffer
    */
-  public ArrowBuf getDataBuffer();
+  ArrowBuf getDataBuffer();
 
   /**
    * Gets the underlying buffer associated with offset vector
    *
    * @return buffer
    */
-  public ArrowBuf getOffsetBuffer();
+  ArrowBuf getOffsetBuffer();
 
-  /* temporarily add these methods here until we remove other vectors
-   * (non-nullable) which are under ValueVector hierarchy and still
-   * use the mutator/accessor interfaces.
+  /**
+   * Gets the number of values
+   * @return
    */
-  public int getValueCount();
+  int getValueCount();
 
-  public void setValueCount(int valueCount);
+  /**
+   * Set number of values in the vector
+   * @return
+   */
+  void setValueCount(int valueCount);
 
-  public Object getObject(int index);
+  /**
+   * Get friendly type object from the vector
+   * @param index
+   * @return
+   */
+  Object getObject(int index);
 
-  public int getNullCount();
+  /**
+   * Returns number of null elements in the vector
+   * @return
+   */
+  int getNullCount();
 
-  public boolean isNull(int index);
+  /**
+   * Check whether an element in the vector is null
+   * @param index
+   * @return
+   */
+  boolean isNull(int index);
 }

java/vector/src/main/java/org/apache/arrow/vector/VariableWidthVector.java

@@ -35,17 +35,5 @@ public interface VariableWidthVector extends ValueVector {
    */
   int getByteCapacity();
 
-  VariableWidthMutator getMutator();
-
-  VariableWidthAccessor getAccessor();
-
-  interface VariableWidthAccessor extends Accessor {
-    int getValueLength(int index);
-  }
-
   int getCurrentSizeInBytes();
-
-  interface VariableWidthMutator extends Mutator {
-    void setValueLengthSafe(int index, int length);
-  }
 }

java/vector/src/main/java/org/apache/arrow/vector/VectorSchemaRoot.java

@@ -140,7 +140,7 @@ public String contentToTSVString() {
     for (int i = 0; i < rowCount; i++) {
       row.clear();
       for (FieldVector v : fieldVectors) {
-        row.add(v.getAccessor().getObject(i));
+        row.add(v.getObject(i));
       }
       printRow(sb, row);
     }