com.davisor.data.stream
Class DataBuffers

java.lang.Object
  com.davisor.data.stream.DataBuffers

public class DataBuffers

extends java.lang.Object

DataBuffers provides tools for DataBuffer manipulation.

Since:

JDK1.1

See Also:

Type

Constructor Summary

DataBuffers()

Method Summary

static DataBuffer	removeNulls(DataBuffer buffer) Copies non-null buffer elements into a new list data buffer.
static DataBuffer[]	toListBuffers(DataBuffer buffer) Copies given data buffer column content into corresponding list data buffers.
static java.util.List[]	toLists(DataBuffer buffer) Copies given data buffer column content into corresponding lists.
static DataBuffer[]	toProxyBuffers(DataBuffer buffer) Creates proxy buffers giving single column views to corresponding columns in given data buffer.

Methods inherited from class java.lang.Object

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

Constructor Detail

DataBuffers

public DataBuffers()

Method Detail

toListBuffers

public static DataBuffer[] toListBuffers(DataBuffer buffer)
                                  throws InvalidDataException

Copies given data buffer column content into corresponding list data buffers.

Parameters:

buffer - buffer to copy content from

Returns:

as many new list data buffers as the buffer contains columns, filled with data

Throws:

InvalidDataException - if buffer content access fails

See Also:

toLists(com.davisor.data.stream.DataBuffer), toProxyBuffers(com.davisor.data.stream.DataBuffer)

toLists

public static java.util.List[] toLists(DataBuffer buffer)
                                throws InvalidDataException

Copies given data buffer column content into corresponding lists.

Parameters:

buffer - buffer to copy content from

Returns:

as many new lists as the buffer contains columns, filled with data

Throws:

InvalidDataException - if buffer content access fails

See Also:

toListBuffers(com.davisor.data.stream.DataBuffer)

toProxyBuffers

public static DataBuffer[] toProxyBuffers(DataBuffer buffer)
                                   throws InvalidDataException,
                                          com.davisor.core.InvalidIndexException

Creates proxy buffers giving single column views to corresponding columns in given data buffer. Unlike toListBuffers(com.davisor.data.stream.DataBuffer), this method does not copy buffer content, but creates tools that just transparently access data in given data buffer.

If the given buffer has already a single simple type column (not of TupleType), the buffer is returned as it is in a single slot array. Otherwise an array of ProxyDataBuffer objects is created and returned.

Parameters:

buffer - source data buffer

Returns:

a number of data buffers equal to columns in the source buffer

Throws:

InvalidDataException - if buffer type resolvation fails

com.davisor.core.InvalidIndexException - if buffer column access fails

See Also:

ProxyDataBuffer, toListBuffers(com.davisor.data.stream.DataBuffer)

removeNulls

public static DataBuffer removeNulls(DataBuffer buffer)
                              throws InvalidDataException

Copies non-null buffer elements into a new list data buffer.

Parameters:

buffer - buffer to copy

Returns:

a new list data buffer containing only non-null elements

Throws:

InvalidDataException - if buffer content access fails