org.moeaframework.core.spi
Class ProblemProvider

java.lang.Object
  org.moeaframework.core.spi.ProblemProvider

Direct Known Subclasses:

ClassLoaderProblems, PropertiesProblems, RotatedProblems, StandardProblems

public abstract class ProblemProvider
extends Object

Defines an SPI for instantiation optimization problems. Problems are identified by a unique name. The methods of the provider must return null if the problem is not supported by the provider.

If the provider can supply the problem but an error occurred during instantiation, the provider may throw a ProviderNotFoundException along with the details causing the exception.

To provide a custom ProblemProvider, first extend this class and implement the two abstract methods. Next, build a JAR file containing the custom provider. Within the JAR file, create the file META-INF/services/org.moeaframework.problem.ProblemProvider containing on a single line the class name of the custom provider. Lastly, add this JAR file to the classpath. Once these steps are completed, the problem(s) are now accessible via the ProblemFactory.getProblem(String) and ProblemFactory.getReferenceSet(String) methods.

As problems names are often used in file names, it is best to avoid characters which are not compatible with the file system. It is suggested that names match the following regular expression: ^[a-zA-Z0-9()\-,]+$.

Constructor Summary

ProblemProvider()
Constructs a problem provider.

Method Summary

abstract Problem	getProblem(String name) Returns the problem with the specified name, or null if this provider does not support the problem.
abstract NondominatedPopulation	getReferenceSet(String name) Returns the reference set for the specified problem, or null if this provider does not support the problem or no reference set is available.

Methods inherited from class java.lang.Object

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

Constructor Detail

ProblemProvider

public ProblemProvider()

Constructs a problem provider.

Method Detail

getProblem

public abstract Problem getProblem(String name)

Returns the problem with the specified name, or null if this provider does not support the problem.

Parameters:

name - the problem name

Returns:

the problem with the specified name, or null if this provider does not support the problem

getReferenceSet

public abstract NondominatedPopulation getReferenceSet(String name)

Returns the reference set for the specified problem, or null if this provider does not support the problem or no reference set is available.

Parameters:

name - the problem name

Returns:

the reference set for the specified problem, or null if this provider does not support the problem or no reference set is available