org.teiid.query.processor.proc

Class AssignmentInstruction

java.lang.Object

org.teiid.query.processor.proc.ProgramInstruction

org.teiid.query.processor.proc.AssignmentInstruction

All Implemented Interfaces:

Cloneable

public class AssignmentInstruction
extends ProgramInstruction

This instruction updates the current variable context with a value for the Variable defined using a DeclareInstruction, the variable value is obtained by either processing a expression or a command(stored as a processplan). The Processing of the command is expected to result in 1 column, 1 row tuple.

Constructor Summary

Constructors

Constructor and Description
AssignmentInstruction()

Method Summary

Modifier and Type	Method and Description
AssignmentInstruction	clone() Override Object.clone() to make the method public.
PlanNode	getDescriptionProperties()
Expression	getExpression()
ElementSymbol	getVariable()
void	process(ProcedurePlan procEnv) Updates the current variable context with a value for the Variable defined using a DeclareInstruction, the variable value is obtained by either processing a expression or a command(stored as a processplan).
Boolean	requiresTransaction(boolean transactionalReads)
void	setExpression(Expression expression)
void	setVariable(ElementSymbol variable)
String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

AssignmentInstruction

public AssignmentInstruction()

Method Detail

process

public void process(ProcedurePlan procEnv)
             throws BlockedException,
                    TeiidComponentException,
                    TeiidProcessingException

Updates the current variable context with a value for the Variable defined using a DeclareInstruction, the variable value is obtained by either processing a expression or a command(stored as a processplan). The Processing of the command is expected to result in 1 column, 1 row tuple, if more than a row is returned an exception is thrown. Also updates the program counter.

Specified by:

process in class ProgramInstruction

Throws:

BlockedException

TeiidComponentException - if error processing command or expression on this instruction

TeiidProcessingException

getDescriptionProperties

public PlanNode getDescriptionProperties()

Specified by:

getDescriptionProperties in class ProgramInstruction

getExpression

public Expression getExpression()

Returns:

Returns the expression.

setExpression

public void setExpression(Expression expression)

Parameters:

expression - The expression to set.

getVariable

public ElementSymbol getVariable()

Returns:

Returns the variable.

setVariable

public void setVariable(ElementSymbol variable)

Parameters:

variable - The variable to set.

toString

public String toString()

Overrides:

toString in class Object

clone

public AssignmentInstruction clone()

Description copied from class: ProgramInstruction

Override Object.clone() to make the method public. This method simply calls super.clone(), deferring to the default shallow cloning. Some ProcessorInstruction subclasses may need to override with custom safe or deep cloning.

Overrides:

clone in class ProgramInstruction

Returns:

shallow clone

See Also:

ProgramInstruction.clone()

requiresTransaction

public Boolean requiresTransaction(boolean transactionalReads)

Overrides:

requiresTransaction in class ProgramInstruction