org.apache.hadoop.hive.ql.exec.vector

Class DoubleColumnVector

java.lang.Object

org.apache.hadoop.hive.ql.exec.vector.ColumnVector

org.apache.hadoop.hive.ql.exec.vector.DoubleColumnVector

public class DoubleColumnVector
extends ColumnVector

This class represents a nullable double precision floating point column vector. This class will be used for operations on all floating point types (float, double) and as such will use a 64-bit double value to hold the biggest possible value. During copy-in/copy-out, smaller types (i.e. float) will be converted as needed. This will reduce the amount of code that needs to be generated and also will run fast since the machine operates with 64-bit words. The vector[] field is public by design for high-performance access in the inner loop of query execution.

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.hadoop.hive.ql.exec.vector.ColumnVector

ColumnVector.Type

Field Summary

Fields

Modifier and Type	Field and Description
static double	NULL_VALUE
double[]	vector

Fields inherited from class org.apache.hadoop.hive.ql.exec.vector.ColumnVector

isNull, isRepeating, noNulls, type

Constructor Summary

Constructors

Constructor and Description
DoubleColumnVector() Use this constructor by default.
DoubleColumnVector(int len) Don't use this except for testing purposes.

Method Summary

Modifier and Type	Method and Description
void	copySelected(boolean selectedInUse, int[] sel, int size, ColumnVector outputColVector)
void	ensureSize(int size, boolean preserveData) Ensure the ColumnVector can hold at least size values.
void	fill(double value)
void	fillWithNulls()
void	flatten(boolean selectedInUse, int[] sel, int size)
void	setElement(int outputElementNum, int inputElementNum, ColumnVector inputColVector) Set the element in this column vector from the given input vector.
void	shallowCopyTo(ColumnVector otherCv) Shallow copy of the contents of this vector to the other vector; replaces other vector's values.
void	stringifyValue(StringBuilder buffer, int row) Print the value for this column into the given string builder.

Methods inherited from class org.apache.hadoop.hive.ql.exec.vector.ColumnVector

decRef, flattenNoNulls, flattenPush, flattenRepeatingNulls, getRef, incRef, init, reset, setRepeating, unFlatten

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

vector

public double[] vector

NULL_VALUE

public static final double NULL_VALUE

See Also:

Constant Field Values

Constructor Detail

DoubleColumnVector

public DoubleColumnVector()

Use this constructor by default. All column vectors should normally be the default size.

DoubleColumnVector

public DoubleColumnVector(int len)

Don't use this except for testing purposes.

Parameters:

len -

Method Detail

copySelected

public void copySelected(boolean selectedInUse,
                         int[] sel,
                         int size,
                         ColumnVector outputColVector)

Specified by:

copySelected in class ColumnVector

fill

public void fill(double value)

fillWithNulls

public void fillWithNulls()

flatten

public void flatten(boolean selectedInUse,
                    int[] sel,
                    int size)

Specified by:

flatten in class ColumnVector

setElement

public void setElement(int outputElementNum,
                       int inputElementNum,
                       ColumnVector inputColVector)

Set the element in this column vector from the given input vector. The inputElementNum will be adjusted to 0 if the input column has isRepeating set. On the other hand, the outElementNum must have been adjusted to 0 in ADVANCE when the output has isRepeating set. IMPORTANT: if the output entry is marked as NULL, this method will do NOTHING. This supports the caller to do output NULL processing in advance that may cause the output results operation to be ignored. Thus, make sure the output isNull entry is set in ADVANCE. The inputColVector noNulls and isNull entry will be examined. The output will only be set if the input is NOT NULL. I.e. noNulls || !isNull[inputElementNum] where inputElementNum may have been adjusted to 0 for isRepeating. If the input entry is NULL or out-of-range, the output will be marked as NULL. I.e. set output noNull = false and isNull[outElementNum] = true. An example of out-of-range is the DecimalColumnVector which can find the input decimal does not fit in the output precision/scale. (Since we return immediately if the output entry is NULL, we have no need and do not mark the output entry to NOT NULL).

Specified by:

setElement in class ColumnVector

stringifyValue

public void stringifyValue(StringBuilder buffer,
                           int row)

Description copied from class: ColumnVector

Print the value for this column into the given string builder.

Specified by:

stringifyValue in class ColumnVector

Parameters:

buffer - the buffer to print into

row - the id of the row to print

ensureSize

public void ensureSize(int size,
                       boolean preserveData)

Description copied from class: ColumnVector

Ensure the ColumnVector can hold at least size values. This method is deliberately *not* recursive because the complex types can easily have more (or less) children than the upper levels.

Overrides:

ensureSize in class ColumnVector

Parameters:

size - the new minimum size

preserveData - should the old data be preserved?

shallowCopyTo

public void shallowCopyTo(ColumnVector otherCv)

Description copied from class: ColumnVector

Shallow copy of the contents of this vector to the other vector; replaces other vector's values.

Overrides:

shallowCopyTo in class ColumnVector