uk.ac.starlink.cdf

Class CdfTableBuilder

java.lang.Object

uk.ac.starlink.table.formats.DocumentedTableBuilder

uk.ac.starlink.cdf.CdfTableBuilder

All Implemented Interfaces:

Documented, DocumentedIOHandler, MultiTableBuilder, TableBuilder

public class CdfTableBuilder
extends DocumentedTableBuilder
implements MultiTableBuilder

Table input handler for NASA CDF (Common Data Format) files.

Since:

24 Jun 2013

Field Summary

Fields

Modifier and Type	Field and Description
static CdfTableProfile	DEFAULT_PROFILE Default CDF-StarTable translation profile.

Constructor Summary

Constructors

Constructor and Description
CdfTableBuilder() Constructs a default Cdf table builder.
CdfTableBuilder(CdfTableProfile profile) Constructs a Cdf table builder with a custom translation profile.

Method Summary

Modifier and Type	Method and Description
boolean	canImport(java.awt.datatransfer.DataFlavor flavor) Returns false.
boolean	canStream() Indicates whether this handler can read tables from a stream.
static CdfTableProfile	createProfile(boolean invarParams, java.lang.String[] descripAttNames, java.lang.String[] unitAttNames, java.lang.String[] blankvalAttNames, java.lang.String[] depend0AttNames) Constructs an instance of CdfTableProfile with some suggestions for attribute names with known semantics.
boolean	docIncludesExample() Indicates whether the serialization of some (short) example table should be added to the user documentation for this handler.
java.lang.String	getFormatName() Returns "CDF".
java.lang.String	getXmlDescription() Returns user-directed documentation in XML format.
StarTable	makeStarTable(DataSource datsrc, boolean wantRandom, StoragePolicy storagePolicy) Constructs a StarTable based on a given DataSource.
TableSequence	makeStarTables(DataSource datsrc, StoragePolicy storagePolicy) Constructs a sequence of StarTables based on a given DataSource.
void	streamStarTable(java.io.InputStream in, TableSink sink, java.lang.String pos) Throws a TableFormatException.

Methods inherited from class uk.ac.starlink.table.formats.DocumentedTableBuilder

getExtensions, looksLikeFile

Methods inherited from class java.lang.Object

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

Methods inherited from interface uk.ac.starlink.table.TableBuilder

looksLikeFile

Methods inherited from interface uk.ac.starlink.table.formats.DocumentedIOHandler

matchesExtension, readText, toLink

Field Detail

DEFAULT_PROFILE

public static final CdfTableProfile DEFAULT_PROFILE

Default CDF-StarTable translation profile. This is based on the ISTP Metadata Guidelines at https://spdf.gsfc.nasa.gov/sp_use_of_cdf.html

Constructor Detail

CdfTableBuilder

public CdfTableBuilder()

Constructs a default Cdf table builder.

CdfTableBuilder

public CdfTableBuilder(CdfTableProfile profile)

Constructs a Cdf table builder with a custom translation profile.

Parameters:

profile - CDF-Startable translation profile

Method Detail

getFormatName

public java.lang.String getFormatName()

Returns "CDF".

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

makeStarTables

public TableSequence makeStarTables(DataSource datsrc,
                                    StoragePolicy storagePolicy)
                             throws java.io.IOException

Description copied from interface: MultiTableBuilder

Constructs a sequence of StarTables based on a given DataSource. If the source is not recognised or this object does not know how to make tables 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.

If the position of the data source is not null, then this method should return a sequence containing a single table, the one which would be returned by the makeStarTable method with that position.

Specified by:

makeStarTables in interface MultiTableBuilder

Parameters:

datsrc - the DataSource containing the table resource

storagePolicy - a StoragePolicy object which may be used to supply scratch storage if the builder needs it

Returns:

an array of StarTables read from 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. I don't think there is a MIME type associated with the CDF format. References to application/x-cdf and application/cdf appear on the web, but neither is IANA registered, and I think they refer to some other 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 java.io.IOException

Throws a TableFormatException. CDF is not suitable for streaming.

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

java.io.IOException - if some other error occurs

getXmlDescription

public java.lang.String getXmlDescription()

Description copied from interface: Documented

Returns user-directed documentation in XML format.

The output should be a sequence of one or more <P> elements, using XHTML-like XML. Since rendering may be done in a number of contexts however, use of the full range of XHTML elements is discouraged. Where possible, the content should stick to simple markup such as the elements P, A, UL, OL, LI, DL, DT, DD EM, STRONG, I, B, CODE, TT, PRE.

Specified by:

getXmlDescription in interface Documented

Returns:

XML description of this object

docIncludesExample

public boolean docIncludesExample()

Description copied from interface: DocumentedIOHandler

Indicates whether the serialization of some (short) example table should be added to the user documentation for this handler. Binary formats, or instances for which the Documented.getXmlDescription() method already includes some example output, should return false.

Specified by:

docIncludesExample in interface DocumentedIOHandler

Returns:

true if the user documentation would benefit from the addition of an example serialization

canStream

public boolean canStream()

Description copied from class: DocumentedTableBuilder

Indicates whether this handler can read tables from a stream.

Specified by:

canStream in class DocumentedTableBuilder

Returns:

true iff this handler can read from streams

createProfile

public static CdfTableProfile createProfile(boolean invarParams,
                                            java.lang.String[] descripAttNames,
                                            java.lang.String[] unitAttNames,
                                            java.lang.String[] blankvalAttNames,
                                            java.lang.String[] depend0AttNames)

Constructs an instance of CdfTableProfile with some suggestions for attribute names with known semantics.

Parameters:

invarParams - true for turning non-row-varying variables into table parameters, false for turning them into variables

descripAttNames - ordered list of names of attributes that might supply description metadata

unitAttNames - ordered list of names of attributes that might supply units metadata

blankvalAttNames - ordered list of names of attributes that might supply magic blank values

depend0AttNames - ordered list of names of attributes that might supply a dependent variable name

Returns:

new profile instance