uk.ac.starlink.table.formats
Class WDCTableBuilder

java.lang.Object
  extended by uk.ac.starlink.table.formats.WDCTableBuilder
All Implemented Interfaces:
TableBuilder

public class WDCTableBuilder
extends java.lang.Object
implements TableBuilder

Implementation of the TableBuilder interface which gets StarTables from World Data Centre-type text files. This format doesn't appear to have a proper name or definition. This implementation is a result of reverse-engineering the format specification by looking at a couple of files.


Constructor Summary
WDCTableBuilder()
           
 
Method Summary
 boolean canImport(java.awt.datatransfer.DataFlavor flavor)
          Returns false since there is no MIME type which targets WDC format.
 java.lang.String getFormatName()
          Returns the name of the format which can be read by this handler.
 StarTable makeStarTable(DataSource datsrc, boolean wantRandom, StoragePolicy storagePolicy)
          Constructs a StarTable based on a given DataSource.
static java.lang.String readLine(java.io.BufferedInputStream strm)
           
 void streamStarTable(java.io.InputStream in, TableSink sink, java.lang.String pos)
          Throws an exception; streaming of WDC tables is not implemented.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

WDCTableBuilder

public WDCTableBuilder()
Method Detail

getFormatName

public java.lang.String getFormatName()
Description copied from interface: TableBuilder
Returns the name of the format which can be read by this handler. Matching against this string may be used by callers to identify or select this handler from a list.

Specified by:
getFormatName in interface TableBuilder
Returns:
one-word description of this handler's format

makeStarTable

public StarTable makeStarTable(DataSource datsrc,
                               boolean wantRandom,
                               StoragePolicy storagePolicy)
                        throws java.io.IOException
Description copied from interface: TableBuilder
Constructs a StarTable based on a given DataSource. If the source is not recognised or this builder does not know how to construct a table from it, then a TableFormatException should be thrown. If this builder thinks it should be able to handle the source but an error occurs during processing, an IOException can be thrown.

The wantRandom parameter is used to indicate whether, ideally, a random-access table should be returned. There is no requirement for the builder to honour this request, but if it knows how to make both random and non-random tables, it can use this flag to decide which to return.

Note: the presence of the wantRandom parameter is somewhat misleading. TableBuilder implementations usually should, and do, ignore it (it would be removed from the interface if it were not for backward compatibility issues). Regardless of the value of this parameter, implementations should return a random-access table only if it is easy for them to do so; in particular they should not use the supplied storagePolicy, or any other resource-expensive measure, to randomise a sequential table just because the wantRandom parameter is true.

Specified by:
makeStarTable in interface TableBuilder
Parameters:
datsrc - the DataSource containing the table resource
wantRandom - whether, preferentially, a random access table should be returned
storagePolicy - a StoragePolicy object which may be used to supply scratch storage if the builder needs it
Returns:
a StarTable made out of datsrc
Throws:
TableFormatException - if the table is not of a kind that can be handled by this handler
java.io.IOException - if an unexpected I/O error occurs during processing

canImport

public boolean canImport(java.awt.datatransfer.DataFlavor flavor)
Returns false since there is no MIME type which targets WDC format.

Specified by:
canImport in interface TableBuilder
Parameters:
flavor - the DataFlavor whose suitability as stream input is to be assessed
Returns:
true iff this builder reckons it stands a good chance of turning a stream of type flavor into a StarTable

streamStarTable

public void streamStarTable(java.io.InputStream in,
                            TableSink sink,
                            java.lang.String pos)
                     throws TableFormatException
Throws an exception; streaming of WDC tables is not implemented. It probably could be if necessary.

Specified by:
streamStarTable in interface TableBuilder
Parameters:
in - input stream containing table data
sink - destination of the table
pos - position identifier describing the location of the table within the stream; see DataSource.getPosition() (may be null)
Throws:
TableFormatException - if the table can't be streamed or the data is malformed

readLine

public static java.lang.String readLine(java.io.BufferedInputStream strm)
                                 throws java.io.IOException
Throws:
java.io.IOException

Copyright © 2004 CLRC: Central Laboratory of the Research Councils. All rights reserved.