uk.ac.starlink.ttools.cone
Class CdsUploadMatcher

java.lang.Object
  uk.ac.starlink.ttools.cone.CdsUploadMatcher

All Implemented Interfaces:

UploadMatcher

public class CdsUploadMatcher
extends Object
implements UploadMatcher

UploadMatcher implementation for the CDS Xmatch service. This class encapsulates all the information about the CDS Xmatch I/O interface.

Since:

14 May 2014

Author:

Mark Taylor

Nested Class Summary

static class

CdsUploadMatcher.VizierMeta Metadata provided for Vizier tables by the CDS Xmatch service.

Field Summary

static String	SIMBAD_NAME Alias for Simbad flat view table.
static boolean	UPLOAD_EMPTY Whether it is safe/recommended to upload empty tables to match.
static String	XMATCH_URL URL for the CDS Xmatch service.

Constructor Summary

CdsUploadMatcher(URL serviceUrl, String tableId, double srArcsec, ServiceFindMode serviceMode, uk.ac.starlink.util.ContentCoding coding)
Constructor.

Method Summary

ColumnPlan	getColumnPlan(uk.ac.starlink.table.ColumnInfo[] resultCols, uk.ac.starlink.table.ColumnInfo[] uploadCols) Returns an object that understands what columns are where in an output table generated from the raw result produced by this matcher.
static String[]	readAliases() Reads the list of VizieR table aliases that can be used with the Xmatch service.
static CdsUploadMatcher.VizierMeta	readVizierMetadata(String vizName) Reads basic table metadata for a given VizieR table.
static String[]	readVizierNames() Reads the list of VizieR table names that can be used with the Xmatch service.
boolean	streamRawResult(ConeQueryRowSequence coneSeq, uk.ac.starlink.table.TableSink rawResultSink, RowMapper<?> rowMapper, long maxrec) Scans a sequence of positional queries, uploads it to a remote service, and writes the returned values to a given sink.
static String	toCdsId(String txt) Turns a user-supplied string referencing a CDS table into an identifier recognisable by the CDS Xmatch service.

Methods inherited from class java.lang.Object

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

Field Detail

XMATCH_URL

public static final String XMATCH_URL

URL for the CDS Xmatch service.

See Also:

Constant Field Values

SIMBAD_NAME

public static final String SIMBAD_NAME

Alias for Simbad flat view table.

See Also:

Constant Field Values

UPLOAD_EMPTY

public static final boolean UPLOAD_EMPTY

Whether it is safe/recommended to upload empty tables to match.

See Also:

Constant Field Values

Constructor Detail

CdsUploadMatcher

public CdsUploadMatcher(URL serviceUrl,
                        String tableId,
                        double srArcsec,
                        ServiceFindMode serviceMode,
                        uk.ac.starlink.util.ContentCoding coding)

Constructor.

Parameters:

serviceUrl - URL of Xmatch service

tableId - identifier of remote table

srArcsec - match radius in arcseconds

serviceMode - type of match

coding - configures HTTP compression for result

Method Detail

streamRawResult

public boolean streamRawResult(ConeQueryRowSequence coneSeq,
                               uk.ac.starlink.table.TableSink rawResultSink,
                               RowMapper<?> rowMapper,
                               long maxrec)
                        throws IOException

Description copied from interface: UploadMatcher

Scans a sequence of positional queries, uploads it to a remote service, and writes the returned values to a given sink.

Both the read and the write should ideally be streamed (read as uploaded and written as received) so that progress can be logged properly.

The result is written to the given rawResultSink (which will probably be a RowStore). To make sense of the table thus written, it is necessary to use the RowMapper supplied to this method and the ColumnPlan available from this object. The RowMapper associates result rows with queries from the input row sequence, and the ColumnPlan knows where the special and other columns are in the result table.

Specified by:

streamRawResult in interface UploadMatcher

Parameters:

coneSeq - sequence of cone-like positional queries

rawResultSink - destination for result rows obtained from the target matcher service

rowMapper - used to label rows; queries are labelled with the value returned from the getIndex method of coneSeq

maxrec - user-supplied limit on the maximum number of output rows, though the service may truncate the result; if <0, no limit is requested

Returns:

true iff the result was truncated due to overflow

Throws:

IOException

getColumnPlan

public ColumnPlan getColumnPlan(uk.ac.starlink.table.ColumnInfo[] resultCols,
                                uk.ac.starlink.table.ColumnInfo[] uploadCols)

Description copied from interface: UploadMatcher

Returns an object that understands what columns are where in an output table generated from the raw result produced by this matcher.

Specified by:

getColumnPlan in interface UploadMatcher

Parameters:

resultCols - columns in the raw result table written by this object's streamRawResult method

uploadCols - columns from the table that will be joined to the raw result to get the output table

Returns:

column plan

toCdsId

public static String toCdsId(String txt)

Turns a user-supplied string referencing a CDS table into an identifier recognisable by the CDS Xmatch service. At present this just prepends a "vizier:" where applicable.

Parameters:

txt - table name

Returns:

xmatch service identifier

readAliases

public static String[] readAliases()
                            throws IOException

Reads the list of VizieR table aliases that can be used with the Xmatch service. This is expected to be a short list (a few tens of entries).

Returns:

alias list

Throws:

IOException

readVizierNames

public static String[] readVizierNames()
                                throws IOException

Reads the list of VizieR table names that can be used with the Xmatch service. This is expected to be several thousand entries long.

Returns:

table name list

Throws:

IOException

readVizierMetadata

public static CdsUploadMatcher.VizierMeta readVizierMetadata(String vizName)
                                                      throws IOException

Reads basic table metadata for a given VizieR table.

Parameters:

vizName - vizier table name or ID

Returns:

basic metadata object

Throws:

IOException