org.knime.base.data.append.row
Class AppendedRowsTable

java.lang.Object
  org.knime.base.data.append.row.AppendedRowsTable

All Implemented Interfaces:

Iterable<DataRow>, DataTable

public class AppendedRowsTable
extends Object
implements DataTable

DataTable implementation that concatenates a set of DataTable objects. All tables should have the same columns (identified by their column name). Missing columns in tables are tried to be filled with missing cells (where it is possible - so far for string, double, int). Non matching column types are adjusted such that they match (if not possible, the column's type is DataCell).

The order of colums of this table is determined by the order of the top table (the first array argument in the constructor)

Author:

Bernd Wiswedel, University of Konstanz

Nested Class Summary

static class

AppendedRowsTable.DuplicatePolicy How to deal with duplicate row ids.

Constructor Summary

AppendedRowsTable(AppendedRowsTable.DuplicatePolicy duplPolicy, String suffix, DataTable... tables)
Concatenates a set of tables.

AppendedRowsTable(DataTable... tables)
Concatenates a set of tables.

AppendedRowsTable(String suffix, DataTable... tables)
Concatenates a set of tables.

Method Summary

static DataTableSpec	generateDataTableSpec(DataTableSpec... tableSpecs) Factory method that determines the final DataTableSpec given the tables.
DataTableSpec	getDataTableSpec() Returns the DataTableSpec object of this table which gives information about the structure of this data table.
(package private) AppendedRowsTable.DuplicatePolicy	getDuplPolicy()
(package private) String	getSuffix()
(package private) DataTable[]	getTables()
RowIterator	iterator() Returns a row iterator which returns each row one-by-one from the table.
AppendedRowsIterator	iterator(ExecutionMonitor exec, int totalRowCount) Get an iterator whose RowIterator.next() method may throw an exception if the execution is canceled.

Methods inherited from class java.lang.Object

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

Constructor Detail

AppendedRowsTable

public AppendedRowsTable(DataTable... tables)

Concatenates a set of tables. Duplicate entries are skipped.

Parameters:

tables - all tables to be appended

Throws:

NullPointerException - if argument is null or contains null elements.

AppendedRowsTable

public AppendedRowsTable(String suffix,
                         DataTable... tables)

Concatenates a set of tables. Duplicate keys may be skipped (suffix argument is null) or may be avoided by appending a fixed suffix to any subsequent occurrence of a duplicate.

Parameters:

tables - all tables to be appended

suffix - suffix to append to duplicate keys or null to skip them

Throws:

NullPointerException - if argument is null or contains null elements

IllegalArgumentException - if suffix is empty (null is ok)

AppendedRowsTable

public AppendedRowsTable(AppendedRowsTable.DuplicatePolicy duplPolicy,
                         String suffix,
                         DataTable... tables)

Concatenates a set of tables. Duplicates are handled according to the policy argument.

Parameters:

duplPolicy - How to deal with duplicate keys.

tables - all tables to be appended

suffix - suffix to append to duplicate keys (must not be null if policy is AppendedRowsTable.DuplicatePolicy.AppendSuffix)

Method Detail

getDataTableSpec

public DataTableSpec getDataTableSpec()

Returns the DataTableSpec object of this table which gives information about the structure of this data table.

Specified by:

getDataTableSpec in interface DataTable

Returns:

the DataTableSpec of this table

iterator

public RowIterator iterator()

Returns a row iterator which returns each row one-by-one from the table.

Specified by:

iterator in interface Iterable<DataRow>

Specified by:

iterator in interface DataTable

Returns:

row iterator

See Also:

DataRow

iterator

public AppendedRowsIterator iterator(ExecutionMonitor exec,
                                     int totalRowCount)

Get an iterator whose RowIterator.next() method may throw an exception if the execution is canceled. In particular if you try to concatenate a table to itself and do not allow duplicates, the RowIterator.next() method runs very long (scanning the entire table to just figure out that there are only duplicates).

Parameters:

exec - the execution monitor for cancel / progress

totalRowCount - the total number rows or negative if unknown

Returns:

an iterator which reacts on cancel events

See Also:

AppendedRowsIterator.RuntimeCanceledExecutionException

getTables

DataTable[] getTables()

Returns:

the tables

getSuffix

String getSuffix()

Returns:

the suffix

getDuplPolicy

AppendedRowsTable.DuplicatePolicy getDuplPolicy()

Returns:

the duplPolicy

generateDataTableSpec

public static final DataTableSpec generateDataTableSpec(DataTableSpec... tableSpecs)

Factory method that determines the final DataTableSpec given the tables.

Parameters:

tableSpecs - the table specs as in the constructor

Returns:

the outcoming {qlink DataTableSpec}

See Also:

AppendedRowsTable(DataTable[])