org.knime.base.node.flowvariable.variableloophead
Class LoopStartVariableNodeModel

java.lang.Object
  org.knime.core.node.NodeModel
      org.knime.base.node.flowvariable.tablerowtovariable.TableToVariableNodeModel
          org.knime.base.node.flowvariable.variableloophead.LoopStartVariableNodeModel

All Implemented Interfaces:

LoopStartNode, LoopStartNodeTerminator

public class LoopStartVariableNodeModel
extends TableToVariableNodeModel
implements LoopStartNodeTerminator

Start of loop: pushes variables in input datatable columns onto stack, taking the values from one row per iteration.

Author:

M. Berthold, University of Konstanz

Constructor Summary

protected

LoopStartVariableNodeModel() One input, one output.

Method Summary

protected PortObjectSpec[]	configure(PortObjectSpec[] inSpecs) Configure method for general port types.
protected PortObject[]	execute(PortObject[] inPOs, ExecutionContext exec) Execute method for general port types.
protected void	reset() Override this function in the derived model and reset your NodeModel.
boolean	terminateLoop()

Methods inherited from class org.knime.base.node.flowvariable.tablerowtovariable.TableToVariableNodeModel

loadInternals, loadValidatedSettingsFrom, pushVariables, saveInternals, saveSettingsTo, validateSettings

Methods inherited from class org.knime.core.node.NodeModel

addWarningListener, configure, continueLoop, execute, executeModel, getAvailableFlowVariables, getCredentialsProvider, getInHiLiteHandler, getLoopEndNode, getLoopStartNode, getNrInPorts, getNrOutPorts, getOutgoingFlowObjectStack, getOutHiLiteHandler, getWarningMessage, notifyViews, notifyWarningListeners, onDispose, peekFlowVariableDouble, peekFlowVariableInt, peekFlowVariableString, peekScopeVariableDouble, peekScopeVariableInt, peekScopeVariableString, pushFlowVariableDouble, pushFlowVariableInt, pushFlowVariableString, pushScopeVariableDouble, pushScopeVariableInt, pushScopeVariableString, removeWarningListener, resetAndConfigureLoopBody, setInHiLiteHandler, setWarningMessage, stateChanged

Methods inherited from class java.lang.Object

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

Constructor Detail

LoopStartVariableNodeModel

protected LoopStartVariableNodeModel()

One input, one output.

Method Detail

configure

protected PortObjectSpec[] configure(PortObjectSpec[] inSpecs)
                              throws InvalidSettingsException

Configure method for general port types. The argument specs represent the input object specs and are guaranteed to be subclasses of the PortObjectSpecs that are defined through the PortTypes given in the constructor. Similarly, the returned output specs need to comply with their port types spec class (otherwise an error is reported by the framework). They may also be null.

For a general description of the configure method refer to the description of the specialized NodeModel.configure(DataTableSpec[]) methods as it addresses more use cases.

Overrides:

configure in class TableToVariableNodeModel

Parameters:

inSpecs - The input data table specs. Items of the array could be null if no spec is available from the corresponding input port (i.e. not connected or upstream node does not produce an output spec). If a port is of type BufferedDataTable.TYPE and no spec is available the framework will replace null by an empty DataTableSpec (no columns) unless the port is marked as optional.

Returns:

The output objects specs or null.

Throws:

InvalidSettingsException - If this node can't be configured.

execute

protected PortObject[] execute(PortObject[] inPOs,
                               ExecutionContext exec)
                        throws Exception

Execute method for general port types. The argument objects represent the input objects and are guaranteed to be subclasses of the PortObject classes that are defined through the PortTypes given in the constructor. Similarly, the returned output objects need to comply with their port types object class (otherwise an error is reported by the framework).

For a general description of the execute method refer to the description of the specialized NodeModel.execute(BufferedDataTable[], ExecutionContext) methods as it addresses more use cases.

Overrides:

execute in class TableToVariableNodeModel

Parameters:

inPOs - The input objects.

exec - For BufferedDataTable creation and progress.

Returns:

The output objects.

Throws:

Exception - If the node execution fails for any reason.

terminateLoop

public boolean terminateLoop()

Specified by:

terminateLoop in interface LoopStartNodeTerminator

Returns:

true if this was the last iteration of the loop, i.e. the tail node must not trigger re-execution of the loop. Some nodes may not be able to provide this and return false all the time. It will be the end node's responsibility to terminate the loop then.

reset

protected void reset()

Override this function in the derived model and reset your NodeModel. All components should unregister themselves from any observables (at least from the hilite handler right now). All internally stored data structures should be released. User settings should not be deleted/reset though.

Overrides:

reset in class TableToVariableNodeModel