Package com.redwood.scheduler.spi.constraint

Interface Constraint

All Superinterfaces:

Serializable

public interface Constraint
extends Serializable

A runtime instance of a constraint. This is a constraint definition that has been instantiated and had its parameters and other runtime references set. The construction of constraint objects has the following phases:

1. The object is constructed by calling ConstraintFactory.create().
2. The setParameterMappings() method will be called to set parameter values.
3. The freeze() will be called.

Method Summary

Modifier and Type	Method	Description
void	execute(ConstraintContext context)	Execute this constraint.
void	freeze()	Freeze the values of constraint parameter mappings for this constraint instance.
String	getDisplayValue(ConstraintContext context, String parameterName, Object value)	Calculate the display value for the given internal value
LOVCollection	getLOV(ConstraintContext context, String parameterName, String query, int startAt, int fetchSize)	Get an LOV for the specified parameter.
LOVSupport	getLOVSupport(ConstraintContext context, String parameterName)	Does this constraint provide LOV support for the specified parameter?
void	setParameterMappings(Iterator<? extends EntityDefinitionConstraintParameterMapping> parameterMappings)	Set the parameter mappings for this constraint.
boolean	supportsArray()	Returns true if this constraint is capable of handling array values, instead of a single value only.
void	update(ConstraintContext context, String parameterName, String changedParameterName)	Notifies constraint about parameter changes
default void	validate()	Validate the constraint parameter mappings provided to this constraint instance.

Method Detail

execute

void execute(ConstraintContext context)
      throws ConstraintViolatedException

Execute this constraint. This method MUST throw a ConstraintViolatedException if the constraint is not met, otherwise it MUST return.

Parameters:

context - the context in which the constraint is to execute.

Throws:

ConstraintViolatedException - if validation fails.

RuntimeException - if there is an error in constraint execution.

getLOV

LOVCollection getLOV(ConstraintContext context,
                     String parameterName,
                     String query,
                     int startAt,
                     int fetchSize)

Get an LOV for the specified parameter.

Parameters:

context - the context in which the constraint is to execute.

parameterName - the name of the parameter for which an LOV is required.

query - a user specified query.

startAt - the starting position for the query results.

fetchSize - the fetch size for the query results.

Returns:

an LOVCollection representing the results.

getLOVSupport

LOVSupport getLOVSupport(ConstraintContext context,
                         String parameterName)

Does this constraint provide LOV support for the specified parameter?

Parameters:

context - the context in which the constraint is to execute.

parameterName - the name of the parameter for which an LOV is required.

Returns:

an LOVSupport object representing the level of LOV support provided by this constraint for the specified parameter.

validate

default void validate()

Validate the constraint parameter mappings provided to this constraint instance.

Throws:

RuntimeException - if the constraint parameter mappings are invalid.

freeze

void freeze()

Freeze the values of constraint parameter mappings for this constraint instance.

setParameterMappings

void setParameterMappings(Iterator<? extends EntityDefinitionConstraintParameterMapping> parameterMappings)

Set the parameter mappings for this constraint.

Parameters:

parameterMappings - an Iterator of EntityDefinitionConstraintParameterMapping objects representing the values of the parameters for this instance of the constraint definition.

getDisplayValue

String getDisplayValue(ConstraintContext context,
                       String parameterName,
                       Object value)

Calculate the display value for the given internal value

Parameters:

context -

parameterName -

value -

Returns:

String

update

void update(ConstraintContext context,
            String parameterName,
            String changedParameterName)

Notifies constraint about parameter changes

Parameters:

context -

parameterName -

changedParameterName -

supportsArray

boolean supportsArray()

Returns true if this constraint is capable of handling array values, instead of a single value only.

Returns:

True if it does, false otherwise.