|Constructor and Description
|Modifier and Type
|Method and Description
Indicates whether this builder is able to turn a resource of media type indicated by flavor into a table.
Indicates whether this handler can read tables from a stream.
Indicates whether the serialization of some (short) example table should be added to the user documentation for this handler.
Returns the name of the format which can be read by this handler.
Returns user-directed documentation in XML format.
StarTable based on a given DataSource.
Sets the maximum number of rows that will be sampled to determine column data types.
Reads a table from an input stream and writes it a row at a time to a sink.
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
public java.lang.String getFormatName()
public boolean canImport(java.awt.datatransfer.DataFlavor flavor)
TableBuilder.streamStarTable(java.io.InputStream, uk.ac.starlink.table.TableSink, java.lang.String) method stands a reasonable chance of
successfully constructing a StarTable from a
DataSource whose input stream is described by the
It will typically make this determination based on the flavor's
This method should only return true if the flavor looks like it is targeted at this builder; for instance a builder which uses a text-based format should return false for a flavor which indicates a MIME type of text/plain.
This method is used in supporting drag and drop functionality
flavor - the DataFlavor whose suitability as stream input
is to be assessed
public StarTable makeStarTable(DataSource datsrc, boolean wantRandom, StoragePolicy policy) throws TableFormatException, java.io.IOException
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
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.
datsrc - the DataSource containing the table resource
wantRandom - whether, preferentially, a random access table
should be returned
policy - a StoragePolicy object which may be used to
supply scratch storage if the builder needs it
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
public void streamStarTable(java.io.InputStream in, TableSink sink, java.lang.String pos) throws TableFormatException
The input stream should be prepared for use prior to calling this method, so implementations should not in general attempt to decompress or buffer istrm.
public boolean canStream()
public boolean docIncludesExample()
method already includes some example output, should return false.
public java.lang.String getXmlDescription()
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.
@ConfigMethod(property="maxSample", doc="<p>Controls how many rows of the input file are sampled\nto determine column datatypes.\nWhen reading ASCII files, since no type information is present\nin the input file, the handler has to look at the column data\nto see what type of value appears to be present\nin each column, before even starting to read the data in.\nBy default it goes through the whole table when doing this,\nwhich can be time-consuming for large tables.\nIf this value is set, it limits the number of rows\nthat are sampled in this data characterisation pass,\nwhich can reduce read time substantially.\nHowever, if values near the end of the table differ\nin apparent type from those near the start,\nit can also result in getting the datatypes wrong.\n</p>", usage="<int>", example="5000") public void setMaxSample(int maxSample)
maxSample - maximum number of rows sampled;
if <=0, all rows are sampled