org.knime.base.node.io.filereader
Class FileReaderPreviewRowIterator

java.lang.Object
  org.knime.core.data.RowIterator
      org.knime.base.node.io.filereader.FileReaderPreviewRowIterator

All Implemented Interfaces:

Iterator<DataRow>

 class FileReaderPreviewRowIterator
extends RowIterator

The iterator for the FileReaderPreviewTable. Wraps the iterator of the underlying file table. Catches exceptions thrown by the underlying iterator, returns an "error row" instead and will end the table. If an error occurres it sets an error message in the underlying table.

Author:

Peter, University of Konstanz

Constructor Summary

FileReaderPreviewRowIterator(FileRowIterator rowIterator, FileReaderPreviewTable previewTable)
A new non-failing file row iterator.

Method Summary

void	dispose() Call this before releasing the last reference to this iterator.
protected void	finalize()
boolean	hasNext() Returns true if there are more rows and false otherwise.
DataRow	next() Returns the next DataRow.

Methods inherited from class org.knime.core.data.RowIterator

remove

Methods inherited from class java.lang.Object

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

Constructor Detail

FileReaderPreviewRowIterator

FileReaderPreviewRowIterator(FileRowIterator rowIterator,
                             FileReaderPreviewTable previewTable)

A new non-failing file row iterator. It wraps the passed iterator and catches its exceptions, converting them into rows with error messages.

Parameters:

rowIterator - the row iterator to wrap

previewTable - the corresponding table this is the iterator from. Needed to pull the sprc from for creating the row in case of an error/exception and to tell the table an error occurred.

Method Detail

finalize

protected void finalize()
                 throws Throwable

Overrides:

finalize in class Object

Throws:

Throwable

dispose

public void dispose()

Call this before releasing the last reference to this iterator. It closes the underlying source. Especially if the iterator didn't run to the end of the table, it is required to call this method. Otherwise the file handle is not released until the garbage collector cleans up. A call to next() after disposing of the iterator has undefined behavior.

hasNext

public boolean hasNext()

Returns true if there are more rows and false otherwise.

Specified by:

hasNext in interface Iterator<DataRow>

Specified by:

hasNext in class RowIterator

Returns:

true if the iterator has more elements, otherwise false

See Also:

RowIterator.next()

next

public DataRow next()

Returns the next DataRow.

Specified by:

next in interface Iterator<DataRow>

Specified by:

next in class RowIterator

Returns:

the next row in the DataTable