org.das2.qstream

Class QdsToD2sStream

java.lang.Object

org.das2.qstream.QdsToD2sStream

Direct Known Subclasses:

QdsToDas22, QdsToDas23

public abstract class QdsToD2sStream
extends java.lang.Object

Base class for QDataSet to das2 stream serializers

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected static class	QdsToD2sStream.PacketXferInfo
protected static class	QdsToD2sStream.QdsXferInfo Determine and hold the information needed to transfer values out of a given QDataSet into a byte buffer.
protected static class	QdsToD2sStream.Sequence1D

Field Summary

Fields

Modifier and Type	Field and Description
protected boolean	bBinary
static int	DEFAUT_FRAC_SEC
static int	DEFAUT_SIG_DIGIT
static int	FIXED_PKT_TAGS
static java.lang.String	FORMAT_2_2
static java.lang.String	FORMAT_2_3_BASIC
static java.lang.String	FORMAT_2_4_GENERAL
static java.lang.String[]	formats
protected int	nSecDigit
protected int	nSigDigit
static int	VAR_PKT_TAGS

Constructor Summary

Constructors

Constructor and Description
QdsToD2sStream() Initialize a binary QDataSet to das2 stream exporter
QdsToD2sStream(int genSigDigits, int fracSecDigits) Initialize a text QDataSet to das2 stream exporter

Method Summary

Modifier and Type	Method and Description
protected boolean	_stripDotProps(QDataSet qds)
abstract boolean	canWrite(QDataSet qds) Determine if the given dataset can be written
protected int	copySimpleProps(MutablePropertyDataSet dsDest, QDataSet dsSrc) Only copy over the simple properties of a dataset, ignore the structural items such as depend, offset, axis, reference, bundle etc.
static java.lang.String	getQdsAxis(QDataSet qds) Determine the name of the das2 axis on which values from a dataset would typically be plotted.
protected QdsToD2sStream.Sequence1D	getSequenceRank1(QDataSet qds, double rMaxJitter) Determine if a rank 1 dataset is really just a sequence
protected java.lang.String	makeNameFromUnits(Units units)
protected org.w3c.dom.Document	newXmlDoc()
abstract boolean	write(QDataSet qds, java.io.OutputStream os) Write the given dataset
protected void	writeData(java.io.OutputStream out, int nTagType, int iPktId, QdsToD2sStream.PacketXferInfo pktXfer)

Methods inherited from class java.lang.Object

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

Field Detail

FORMAT_2_2

public static final java.lang.String FORMAT_2_2

See Also:

Constant Field Values

FORMAT_2_3_BASIC

public static final java.lang.String FORMAT_2_3_BASIC

See Also:

Constant Field Values

FORMAT_2_4_GENERAL

public static final java.lang.String FORMAT_2_4_GENERAL

See Also:

Constant Field Values

formats

public static final java.lang.String[] formats

DEFAUT_FRAC_SEC

public static final int DEFAUT_FRAC_SEC

See Also:

Constant Field Values

DEFAUT_SIG_DIGIT

public static final int DEFAUT_SIG_DIGIT

See Also:

Constant Field Values

FIXED_PKT_TAGS

public static final int FIXED_PKT_TAGS

See Also:

Constant Field Values

VAR_PKT_TAGS

public static final int VAR_PKT_TAGS

See Also:

Constant Field Values

nSigDigit

protected int nSigDigit

nSecDigit

protected int nSecDigit

bBinary

protected boolean bBinary

Constructor Detail

QdsToD2sStream

public QdsToD2sStream()

Initialize a binary QDataSet to das2 stream exporter

QdsToD2sStream

public QdsToD2sStream(int genSigDigits,
                      int fracSecDigits)

Initialize a text QDataSet to das2 stream exporter

Parameters:

genSigDigits - The number of significant digits used for general text value data output. If you don't know what else to use, 5 is typically a fine precision without being ridiculous.

fracSecDigits - The number of fractional seconds digits to use for ISO-8601 date-time values. The number of fraction seconds can be set as low as 0 and as high as 12 (picoseconds). If successive time values vary by less than the specified precision (but not 0, repeats are accepted) then stream writing fails. Use 3 (i.e. microseconds) if you don't know what else to choose.

Method Detail

canWrite

public abstract boolean canWrite(QDataSet qds)

Determine if the given dataset can be written

Parameters:

qds -

Returns:

write

public abstract boolean write(QDataSet qds,
                              java.io.OutputStream os)
                       throws java.io.IOException

Write the given dataset

Parameters:

qds -

os -

Returns:

Throws:

java.io.IOException

writeData

protected void writeData(java.io.OutputStream out,
                         int nTagType,
                         int iPktId,
                         QdsToD2sStream.PacketXferInfo pktXfer)
                  throws java.io.IOException

Throws:

java.io.IOException

makeNameFromUnits

protected java.lang.String makeNameFromUnits(Units units)

_stripDotProps

protected boolean _stripDotProps(QDataSet qds)

newXmlDoc

protected org.w3c.dom.Document newXmlDoc()

getSequenceRank1

protected QdsToD2sStream.Sequence1D getSequenceRank1(QDataSet qds,
                                                     double rMaxJitter)

Determine if a rank 1 dataset is really just a sequence

Parameters:

qds -

rMaxJitter - Recommend 1e-4 if no other values comes to mind

Returns:

A Sequence1D object with minval and interval set.

getQdsAxis

public static java.lang.String getQdsAxis(QDataSet qds)

Determine the name of the das2 axis on which values from a dataset would typically be plotted. This is a duck-typing check. Which looks at the number of dependencies and planes in a dataset. If the dataset has a PLANE_0 property, the axis of the PLANE_0 values is returned instead of the axis of the primary dataset.

Parameters:

qds -

Returns:

one of "x", "y", "z","w" or null if we can't figure it out.

copySimpleProps

protected int copySimpleProps(MutablePropertyDataSet dsDest,
                              QDataSet dsSrc)

Only copy over the simple properties of a dataset, ignore the structural items such as depend, offset, axis, reference, bundle etc.

Parameters:

dsDest -

dsSrc -

Returns: