uk.ac.starlink.votable

Class VOTableWriter

java.lang.Object

uk.ac.starlink.votable.VOTableWriter

All Implemented Interfaces:

MultiStarTableWriter, StarTableWriter

public class VOTableWriter
extends java.lang.Object
implements StarTableWriter, MultiStarTableWriter

Implementation of the StarTableWriter interface for VOTables. The dataFormat and inline attributes can be modified to affect how the bulk cell data are output - this may be in TABLEDATA, FITS, BINARY or BINARY2 format, and in the latter three cases may be either inline as base64 encoded CDATA or to a separate stream.

Some of the Auxiliary metadata items of the ColumnInfo metadata from written tables are respected:

• Tables.NULL_VALUE_INFO: sets the value of "magic" blank value for integer columns
• Tables.UBYTE_FLAG_INFO: if set to Boolean.TRUE and if the column has content class Short or short[], the data will be written with datatype="unsignedByte" instead of (signed 16-bit) "short".
• The COOSYS_*_INFO and TIMESYS_*_INFO items defined in the VOStarTable class; suitable COOSYS/TIMESYS elements will be written and referenced as required to honour these items.
• Various other of the *_INFO items defined in the VOStarTable class; this has the effect that VOTable column attributes read in from a VOTable will be passed through if the same table is written out to a VOTable (or VOTable-based format like FITS-plus).

Field Summary

Fields

Modifier and Type	Field and Description
static java.lang.String	DEFAULT_XML_DECLARATION Default XML declaration in written documents.

Constructor Summary

Constructors

Constructor and Description
VOTableWriter() Constructs a default VOTableWriter.
VOTableWriter(DataFormat dataFormat, boolean inline) Constructs a VOTableWriter with specified output type and default VOTable version.
VOTableWriter(DataFormat dataFormat, boolean inline, VOTableVersion version) Constructs a VOTableWriter with specified output characterstics and a given version of the VOTable standard.

Method Summary

Modifier and Type	Method and Description
DataFormat	getDataFormat() Returns the format in which this writer will output the bulk table data.
java.lang.String	getFormatName() Gives the name of the format which is written by this writer.
boolean	getInline() Indicates whether STREAM elements will be written inline or to an external file in the case of FITS and BINARY encoding.
java.lang.String	getMimeType() Returns a string suitable for use as the value of a MIME Content-Type header.
static StarTableWriter[]	getStarTableWriters() Returns a list of votable writers with variant values of attributes.
VOTableVersion	getVotableVersion() Returns the version of the VOTable standard to which the output of this writer conforms.
boolean	getWriteSchemaLocation() Indicates whether the schema location attribute will be written on opening VOTABLE tags.
java.lang.String	getXMLDeclaration() Returns the XML declaration which is used by this writer at the head of any document written.
boolean	looksLikeFile(java.lang.String filename) Returns true for filenames with the extension ".xml", ".vot" or ".votable";
void	setDataFormat(DataFormat format) Sets the format in which the table data will be output.
void	setInline(boolean inline) Sets whether STREAM elements should be written inline or to an external file in the case of FITS and BINARY encoding.
void	setVotableVersion(VOTableVersion version) Sets the version of the VOTable standard to which the output of this writer will conform.
void	setWriteSchemaLocation(boolean writeSchemaLocation) Determines whether the schema location attribute will be written on opening VOTABLE tags.
void	setXMLDeclaration(java.lang.String xmlDecl) Sets the XML declaration which will be used by this writer at the head of any document written.
java.lang.String	toString()
protected void	writeBetweenTableXML(java.io.BufferedWriter writer) Outputs text between one table (TABLE and possibly other associated elements) and the next.
void	writeInlineStarTable(StarTable startab, java.io.BufferedWriter writer) Writes a table directly to a stream.
void	writeInlineStarTables(StarTable[] startabs, java.io.BufferedWriter writer) Writes multiple tables directly to a stream.
protected void	writePostTableXML(java.io.BufferedWriter writer) Outputs all the text required after any tables in the output table document.
protected void	writePreTableXML(java.io.BufferedWriter writer) Outputs all the text required before any tables are written.
void	writeStarTable(StarTable startab, java.io.OutputStream out) Writes a StarTable to a given stream; must be inline.
void	writeStarTable(StarTable startab, java.io.OutputStream out, java.io.File file) Writes a StarTable to a given stream.
void	writeStarTable(StarTable startab, java.lang.String location, StarTableOutput sto) Writes a StarTable to a given location.
void	writeStarTables(TableSequence tableSeq, java.io.OutputStream out) Writes a sequence of tables to a given stream; must be inline.
void	writeStarTables(TableSequence tableSeq, java.io.OutputStream out, java.io.File file) Writes a sequence of tables to a given stream.
void	writeStarTables(TableSequence tableSeq, java.lang.String location, StarTableOutput sto) Writes a sequence of tables to a given location.

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_XML_DECLARATION

public static final java.lang.String DEFAULT_XML_DECLARATION

Default XML declaration in written documents.

See Also:

Constant Field Values

Constructor Detail

VOTableWriter

public VOTableWriter()

Constructs a default VOTableWriter. Output is in TABLEDATA format.

VOTableWriter

public VOTableWriter(DataFormat dataFormat,
                     boolean inline)

Constructs a VOTableWriter with specified output type and default VOTable version.

Parameters:

dataFormat - the format in which tables will be written

inline - whether output of streamed formats should be inline and base64-encoded or not

VOTableWriter

public VOTableWriter(DataFormat dataFormat,
                     boolean inline,
                     VOTableVersion version)

Constructs a VOTableWriter with specified output characterstics and a given version of the VOTable standard.

Parameters:

dataFormat - the format in which tables will be written

inline - whether output of streamed formats should be inline and base64-encoded or not

version - version of the VOTable standard

Method Detail

writeStarTable

public void writeStarTable(StarTable startab,
                           java.lang.String location,
                           StarTableOutput sto)
                    throws java.io.IOException

Writes a StarTable to a given location.

Specified by:

writeStarTable in interface StarTableWriter

Parameters:

startab - the table to write

location - the filename to which to write the table

sto - object used for location resolution

Throws:

TableFormatException - if startab cannot be written to location

java.io.IOException - if there is some I/O error

writeStarTables

public void writeStarTables(TableSequence tableSeq,
                            java.lang.String location,
                            StarTableOutput sto)
                     throws java.io.IOException

Writes a sequence of tables to a given location. They are written as separate TABLE elements in the same VOTable document.

Specified by:

writeStarTables in interface MultiStarTableWriter

Parameters:

tableSeq - table sequence

location - the filename to which to write the table

sto - object used for location resolution

Throws:

java.io.IOException

writeStarTable

public void writeStarTable(StarTable startab,
                           java.io.OutputStream out)
                    throws java.io.IOException

Writes a StarTable to a given stream; must be inline. Same as writeStarTable(startab,out,(File)null).

Specified by:

writeStarTable in interface StarTableWriter

Parameters:

startab - the table to write

out - the stream down which to write the table

Throws:

TableFormatException - if this table cannot be written to a stream

java.io.IOException - if there is some I/O error

writeStarTables

public void writeStarTables(TableSequence tableSeq,
                            java.io.OutputStream out)
                     throws java.io.IOException

Writes a sequence of tables to a given stream; must be inline. Same as writeStarTables(tableSeq,out,null).

Specified by:

writeStarTables in interface MultiStarTableWriter

Parameters:

tableSeq - tables to write

out - destination stream

Throws:

java.io.IOException

writeStarTable

public void writeStarTable(StarTable startab,
                           java.io.OutputStream out,
                           java.io.File file)
                    throws java.io.IOException

Writes a StarTable to a given stream.

Parameters:

startab - the table to write

out - the stream down which to write the table

file - the filename to which out refers; this is used if necessary to come up with a suitable filename for related files which need to be written. May be null.

Throws:

java.io.IOException

writeStarTables

public void writeStarTables(TableSequence tableSeq,
                            java.io.OutputStream out,
                            java.io.File file)
                     throws java.io.IOException

Writes a sequence of tables to a given stream.

Parameters:

tableSeq - table sequence to write

out - destination stream

file - the filename to which out refers; this is used if necessary to come up with a suitable filename for related files which need to be written. May be null.

Throws:

java.io.IOException

writeInlineStarTable

public void writeInlineStarTable(StarTable startab,
                                 java.io.BufferedWriter writer)
                          throws java.io.IOException

Writes a table directly to a stream.

Parameters:

startab - table to write

writer - destination stream

Throws:

java.io.IOException

writeInlineStarTables

public void writeInlineStarTables(StarTable[] startabs,
                                  java.io.BufferedWriter writer)
                           throws java.io.IOException

Writes multiple tables directly to a stream.

Parameters:

startabs - tables

writer - destination stream

Throws:

java.io.IOException

writePreTableXML

protected void writePreTableXML(java.io.BufferedWriter writer)
                         throws java.io.IOException

Outputs all the text required before any tables are written. This method can be overridden to alter the behaviour of the writer if required.

Parameters:

writer - destination stream

Throws:

java.io.IOException

See Also:

writePostTableXML(java.io.BufferedWriter)

writeBetweenTableXML

protected void writeBetweenTableXML(java.io.BufferedWriter writer)
                             throws java.io.IOException

Outputs text between one table (TABLE and possibly other associated elements) and the next. It's only called as a separator between adjacent tables, not at the start or end of a sequence of them; hence it's not called if only a single table is being output. This method can be overridden to alter the behaviour of the writer if required.

This method closes one RESOURCE element and opens another one.

Parameters:

writer - destination stream

Throws:

java.io.IOException

writePostTableXML

protected void writePostTableXML(java.io.BufferedWriter writer)
                          throws java.io.IOException

Outputs all the text required after any tables in the output table document. This method can be overridden to alter the behaviour of this writer if required.

Parameters:

writer - destination stream

Throws:

java.io.IOException

See Also:

writePreTableXML(java.io.BufferedWriter)

looksLikeFile

public boolean looksLikeFile(java.lang.String filename)

Returns true for filenames with the extension ".xml", ".vot" or ".votable";

Specified by:

looksLikeFile in interface StarTableWriter

Parameters:

filename - name of the file

Returns:

true if filename looks like the home of a VOTable

getFormatName

public java.lang.String getFormatName()

Description copied from interface: StarTableWriter

Gives the name of the format which is written by this writer. Matching against this string may be used by callers to identify or select this writer from a list.

Specified by:

getFormatName in interface StarTableWriter

Returns:

a short string identifying the output format of this writer

getMimeType

public java.lang.String getMimeType()

Description copied from interface: StarTableWriter

Returns a string suitable for use as the value of a MIME Content-Type header. If no suitable MIME type is available or known, one of "application/octet-stream" (for binary formats) or "text/plain" for ASCII ones) is recommended.

Specified by:

getMimeType in interface StarTableWriter

Returns:

MIME content type

setDataFormat

public void setDataFormat(DataFormat format)

Sets the format in which the table data will be output.

Parameters:

format - bulk data format

getDataFormat

public DataFormat getDataFormat()

Returns the format in which this writer will output the bulk table data.

Returns:

bulk data format

setInline

public void setInline(boolean inline)

Sets whether STREAM elements should be written inline or to an external file in the case of FITS and BINARY encoding.

Parameters:

inline - true iff streamed data will be encoded inline in the STREAM element

getInline

public boolean getInline()

Indicates whether STREAM elements will be written inline or to an external file in the case of FITS and BINARY encoding.

Returns:

true iff streamed data will be encoded inline in the STREAM element

setXMLDeclaration

public void setXMLDeclaration(java.lang.String xmlDecl)

Sets the XML declaration which will be used by this writer at the head of any document written. By default this is the value of DEFAULT_XML_DECLARATION.

Parameters:

xmlDecl - new XML declaration

getXMLDeclaration

public java.lang.String getXMLDeclaration()

Returns the XML declaration which is used by this writer at the head of any document written.

Returns:

XML declaration

setVotableVersion

public void setVotableVersion(VOTableVersion version)

Sets the version of the VOTable standard to which the output of this writer will conform.

Parameters:

version - new version

getVotableVersion

public VOTableVersion getVotableVersion()

Returns the version of the VOTable standard to which the output of this writer conforms.

Returns:

version

setWriteSchemaLocation

public void setWriteSchemaLocation(boolean writeSchemaLocation)

Determines whether the schema location attribute will be written on opening VOTABLE tags.

Parameters:

writeSchemaLocation - whether to write xsi:schemaLocation atts

getWriteSchemaLocation

public boolean getWriteSchemaLocation()

Indicates whether the schema location attribute will be written on opening VOTABLE tags.

Returns:

whether xsi:schemaLocation attributes will be written

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

getStarTableWriters

public static StarTableWriter[] getStarTableWriters()

Returns a list of votable writers with variant values of attributes.

Returns:

non-standard VOTableWriters.