org.pentaho.di.core.row

Class RowDataUtil

java.lang.Object

org.pentaho.di.core.row.RowDataUtil

public class RowDataUtil
extends Object

This class of static methods can be used to manipulate rows: add, delete, resize, etc... That way, when we want to go for a metadata driven system with hiding deletes, over sized arrays etc, we can change these methods to find occurrences.

For example, a step adding a field to the row should always call

 public static Object[] resizeArray(Object[] objects, int newSize)
 

which will either physically resize the array or return the original row, in case it was over-allocated and has enough slots. If a step needs to create new rows from scratch, it should use allocateRowData() which will return a somewhat over-allocated object array to fit the desired number of fields.

Author:

Matt

Field Summary

Fields

Modifier and Type	Field and Description
static int	OVER_ALLOCATE_SIZE

Constructor Summary

Constructors

Constructor and Description
RowDataUtil()

Method Summary

Methods

Modifier and Type	Method and Description
static Object[]	addRowData(Object[] one, int sourceLength, Object[] two) Add two arrays and make one new one.
static Object[]	addValueData(Object[] rowData, int length, Object extra) Add a single value to a row of data
static Object[]	allocateRowData(int size) Allocate a new Object array.
static Object[]	createResizedCopy(Object[][] objects, int[] lengths) This method concatenates data from an array of rows, each with their own specific length.
static Object[]	createResizedCopy(Object[] objects, int newSize) Resize an object array making it bigger, over allocate, always create a copy of the original array, even if there's enough room in the old one.
static Object[]	removeItem(Object[] objects, int index) Remove an item from an Object array.
static Object[]	removeItems(Object[] rowData, int[] index) Remove a number of items in a row of data.
static Object[]	resizeArray(Object[] objects, int newSize) Resize an object array making it bigger, over allocate, return the original array if there's enough room.

Methods inherited from class java.lang.Object

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

Field Detail

OVER_ALLOCATE_SIZE

public static int OVER_ALLOCATE_SIZE

Constructor Detail

RowDataUtil

public RowDataUtil()

Method Detail

allocateRowData

public static Object[] allocateRowData(int size)

Allocate a new Object array. However, over allocate by a constant factor to make adding values faster.

Parameters:

size - the minimum size to allocate.

Returns:

the newly allocated object array

resizeArray

public static Object[] resizeArray(Object[] objects,
                   int newSize)

Resize an object array making it bigger, over allocate, return the original array if there's enough room.

Parameters:

objects -

newSize -

Returns:

A new object array, resized.

createResizedCopy

public static Object[] createResizedCopy(Object[] objects,
                         int newSize)

Resize an object array making it bigger, over allocate, always create a copy of the original array, even if there's enough room in the old one.

Parameters:

objects - the original row

newSize - the new size

Returns:

A new object array, resized.

createResizedCopy

public static Object[] createResizedCopy(Object[][] objects,
                         int[] lengths)

This method concatenates data from an array of rows, each with their own specific length.

Parameters:

objects -

lengths -

Returns:

The concatenated array of objects.

removeItem

public static Object[] removeItem(Object[] objects,
                  int index)

Remove an item from an Object array. This is a slow operation, later we want to just flag this object and discard it at the next resize. The question is of-course if it makes that much of a difference in the end.

Parameters:

objects -

index -

Returns:

addRowData

public static Object[] addRowData(Object[] one,
                  int sourceLength,
                  Object[] two)

Add two arrays and make one new one.

Parameters:

one - The first array

the - length of the row data or of it's longer, the location of the new extra value in the returned data row

two - The second array

Returns:

a new Array containing all elements from one and two after one another

addValueData

public static Object[] addValueData(Object[] rowData,
                    int length,
                    Object extra)

Add a single value to a row of data

Parameters:

rowData - The original row of data

the - length of the row data or of it's longer, the location of the new extra value in the returned data row

extra - The extra value to add

Returns:

a new Array containing all elements, including the extra one

removeItems

public static Object[] removeItems(Object[] rowData,
                   int[] index)

Remove a number of items in a row of data.

Parameters:

rowData - the row of data to remove from

index - the index of all the items in the source table to remove. We don't check if the same index gets deleted twice!