When using toList() ConstraintCollector in optaplanner 8.1 like:
factory.from(Lesson.class)
.groupBy(Lesson::getCourse, ConstraintCollectors.toList()).penalize(...);
I run into:
Exception executing consequence for rule "foo" in model: java.lang.ClassCastException: class model.Lesson cannot be cast to class java.util.List (model.Lesson is in unnamed module of loader 'app'; java.util.List is in module java.base of loader 'bootstrap')
at org.drools.core.runtime.rule.impl.DefaultConsequenceExceptionHandler.handleException(DefaultConsequenceExceptionHandler.java:39)
Question: Is this a optaplanner bug, or is my code wrong?
The most simple complete reproducer I find is:
#PlanningSolution
public class OptaplannerIssue2 implements ConstraintProvider {
#Override
public Constraint[] defineConstraints(ConstraintFactory factory) {
return new Constraint[] {factory.from(IssueEntity.class)
.groupBy(IssueEntity::getValue, ConstraintCollectors.toList())
.penalize("x", HardSoftScore.ofHard(1), (entity, enityList) -> 2)};
}
#PlanningScore
private HardSoftScore score = HardSoftScore.ZERO;
#PlanningEntityCollectionProperty
private final List<IssueEntity> entities = new ArrayList<IssueEntity>();
public List<IssueEntity> getEntities() {
return entities;
}
#ValueRangeProvider(id = "valueRange")
public CountableValueRange<Integer> getValueRange() {
return ValueRangeFactory.createIntValueRange(0, 4);
}
public static void main() {
// create Entity
OptaplannerIssue2 issue = new OptaplannerIssue2();
IssueEntity e1 = new IssueEntity();
issue.entities.add(e1);
// solve
SolverFactory<OptaplannerIssue2> solverFactory = SolverFactory.create(new SolverConfig()
.withEnvironmentMode(EnvironmentMode.FULL_ASSERT).withSolutionClass(OptaplannerIssue2.class)
.withEntityClasses(IssueEntity.class)
.withScoreDirectorFactory(
new ScoreDirectorFactoryConfig().withConstraintProviderClass(OptaplannerIssue2.class))
.withTerminationConfig(new TerminationConfig().withSecondsSpentLimit(5L)).withPhases(
new ConstructionHeuristicPhaseConfig()
.withConstructionHeuristicType(ConstructionHeuristicType.FIRST_FIT),
new LocalSearchPhaseConfig().withLocalSearchType(LocalSearchType.LATE_ACCEPTANCE)));
Solver<OptaplannerIssue2> solver = solverFactory.buildSolver();
solver.solve(issue);
}
}
With the following entity-class:
#PlanningEntity
public class IssueEntity {
#PlanningVariable(valueRangeProviderRefs = {"valueRange"})
Integer value;
public Integer getValue() {
return value;
}
}
In the related thread: Optaplanner GroupBy with toList not working as expected the questioner didn't provide all information to commentators trying to help and when I provided reproducer there I got deleted, so I had to ask new question.
The behavior you describe is a bug in OptaPlanner, which we have now fixed. Please upgrade to the next release of OptaPlanner, which at the time of writing this answer will be OptaPlanner 8.2.0.
For details, see PLANNER-2305.
Related
Following is my code isolation.
Interactable Interface.
public interface Interactable <E extends Interactable> {
List<Person> personsInteracting = new ArrayList<>();
List<Person> personsWaiting = new ArrayList<>();
long INTERACTION_TIME = 5 * 60;
default int getNumberOfPeopleInteracting () {
return personsInteracting.size();
}
default int getNumberOfPeopleWaiting () {
return personsWaiting.size();
}
boolean isMultipleActionsAllowed ();
boolean isFurtherActionsAllowed ();
public abstract boolean tryOccupiedBy (final Person person, final Interactions interaction)
throws InteractionNotPossibleException;
E getObject ();
EnumSet<Interactions> getInteractions ();
}
InteractiveObject Abstract Class
public abstract class InteractiveObject implements Interactable {
protected final String name;
protected int numberOfSimultaneousInteractions;
protected Interactions currentInteraction;
public InteractiveObject (final String name) {
this.name = name;
}
#Override
public boolean isMultipleActionsAllowed () {
return numberOfSimultaneousInteractions > 1;
}
#Override
public boolean isFurtherActionsAllowed () {
return personsInteracting.isEmpty() ||
(getNumberOfPeopleInteracting() > numberOfSimultaneousInteractions);
}
#Override
public boolean tryOccupiedBy (final Person person, final Interactions interaction)
throws InteractionNotPossibleException {
boolean isOccupied = false;
if (!isFurtherActionsAllowed()) {
throw new InteractionNotPossibleException(this + " is already in use by some other " +
"person.");
}
personsInteracting.add(person);
currentInteraction = interaction;
return isOccupied;
}
#Override
public String toString () {
return name;
}
public int getNumberOfSimultaneousInteractions () {
return numberOfSimultaneousInteractions;
}
}
Chair (One of the child class)
public class Chair extends InteractiveObject {
private final EnumSet<Interactions> INTERACTIONS = EnumSet.copyOf(Arrays.asList(
new Interactions[] {Interactions.DRAG, Interactions.SIT}));
public Chair (final String objectName) {
super(objectName);
super.numberOfSimultaneousInteractions = 1;
}
#Override
public Interactable getObject () {
return this;
}
#Override
public EnumSet<Interactions> getInteractions () {
return INTERACTIONS;
}
}
Here is the piece of code that executes and brings the problem, this question is asked for.
final InteractiveObject chair1 = new Chair("Chair1");
final Person person1 = new Person("Person1");
final Room room = new Room("Room1", 2, 2);
room.personEnters(person1);
room.putObject(chair1);
person1.tryOccupying(chair1);
Above piece of code, successfully occupies the chair object. Now,
final InteractiveObject chair2 = new Chair("Chair2");
final Person person2 = new Person("Person2");
final Room room2 = new Room("Room2", 2, 2);
room2.personEnters(person2);
room2.putObject(chair2);
person2.tryOccupying(chair2);
This piece of code doesn't let the person2 occupy since my code states that 1 person is already interacting with chair2, where as no one is interacting with it.
Solution of my problem:
I moved my List of personInteracting to InteractiveObject and function tryOccupiedBy to each child class and everything works fine.
Questions:
I put personsInteracting in Interactable interface since I believe that every future implementation of Interactable will have it. Developers won't have to implement themselves. (But perhaps this idea seems to be wrong)
If tryOccupiedBy function has same implementation, what is the purpose of whole OOP?
I now know that the isolation was wrong and I know where to place the pieces to get the results. But can someone kindly point me out about some OOP concept which I did not understand and should be implemented in a much better way?
The default keyword was not added to the Java language to do the kind of thing which you seem to be trying to achieve. Data defined in an interface is intended to be constant - the modifiers 'public static' are automatically applied to any field definitions in an interface. If you create a default method in the interface then it must either be stateless or act directly only on purely statically available state. Default methods can call other interface methods to modify instance state, .
By placing personsInteracting field in the interface, you made the same instance common to every object implementing that interface, and so your tryOccupying method was acting on purely global state.
So, the purpose of having default methods in the Java language is to support adding new methods to interfaces in a backwards compatible fashion, nothing more. You shouldn't reuse it as a generic form of code re-use - it was never intended for that and you'll get (as you did) weird behaviour.
You didn't have to put tryOccupiedBy in the child classes, however, so you didn't have to have a load of duplicated code. You could still declare the method signature in the interface (which is what interfaces are generally supposed to do) and then implement the common method in your abstract base class. By putting the data fields in the base class, you make them instance fields and so they are not shared between objects.
public interface Interactable <E extends Interactable> {
...
boolean tryOccupiedBy (final Person person, final Interactions interaction)
throws InteractionNotPossibleException;
...
}
public abstract class InteractiveObject implements Interactable {
private final List<Person> personsInteracting = new ArrayList<>();
private final List<Person> personsWaiting = new ArrayList<>();
...
#Override
public final boolean tryOccupiedBy (final Person person, final Interactions interaction)
throws InteractionNotPossibleException {
boolean isOccupied = false;
if (!isFurtherActionsAllowed()) {
throw new InteractionNotPossibleException(this + " is already in use by some other " +
"person.");
}
personsInteracting.add(person);
currentInteraction = interaction;
return isOccupied;
}
...
}
I am receiving this error when I compile
The type XXX must implement the inherited abstract method
I have three files
A default implementation [com.SafeReaderIMPL.java]
public class SafeReaderIMPL implements ISafeReader {
private boolean successfulRead;
public SafeReaderIMPL() {
successfulRead = true;
}
protected void fail() {
successfulRead = false;
}
#Override
public boolean isSuccessfulRead() {
return successfulRead;
}
}
An interface file [com.ISafeReader.java]
public interface ISafeReader {
public boolean isSuccessfulRead();
}
An apsect (using annotations) [com.SafeReaderAspect.java]
#Aspect
public class SafeReaderAspect {
#DeclareParents(value = "com.BadReader", defaultImpl = SafeReaderIMPL.class)
public ISafeReader implementedInterface;
#AfterThrowing(pointcut = "execution(* *.*(..)) && this(m)", throwing = "e")
public void handleBadRead(JoinPoint joinPoint, ISafeReader m, Throwable e) {
((SafeReaderIMPL)m).fail();
}
}
And a Test Class [com.BadReader]
public class BadReader {
public void fail() throws Throwable {
throw new Throwable();
}
}
I compile the first three files in a separate jar using
ajc -source 1.8 -sourceroots . -outjar aspectLib.jar
I then compile the second file using the aspectLib like so
ajc -source 1.8 -sourceroots . -aspectpath ./aspectLib.jar -outjar common.jar
When I go to compile the second jar I get the error. I am using the latest stable version of AspectJ 1.8.3
BadReader.java:10 [error] The type BadReader must implement the
inherited abstract method ISafeReader.isSuccessfulRead() public class
BadReader {
^^^^^^^^
The problem is not two-step compilation as such, but the fact that #DeclareParents in #AspectJ syntax in not 100% compatible with declare parents in native syntax. Actually, #DeclareParents for introducing default interface implementations is superseded by #DeclareMixin (see this bug ticket), but the downside of the mixin approach is that you do not have a real A implements B scenario there, i.e. you cannot cast as you wish in your after-throwing advice, so this is also not a good option in your case.
So what do you do if you want to keep the two-step compilation approach? Just use native syntax:
Interface:
package com;
public interface ISafeReader {
boolean isSuccessfulRead();
}
Default implementation:
package com;
public class SafeReaderIMPL implements ISafeReader {
private boolean successfulRead;
public SafeReaderIMPL() { successfulRead = true; }
public void fail() { successfulRead = false; }
#Override public boolean isSuccessfulRead() { return successfulRead; }
}
ITD aspect:
package com;
public aspect SafeReaderAspect {
declare parents : com.BadReader implements SafeReaderIMPL;
after(ISafeReader safeReader) throwing : execution(* *(..)) && this(safeReader) {
System.out.println(thisJoinPoint + " - calling 'fail()' before rethrowing error");
((SafeReaderIMPL) safeReader).fail();
}
}
ITD target class with sample main method:
package com;
public class BadReader {
public void doSomething() {
throw new RuntimeException("my error");
}
public static void main(String[] args) {
BadReader badReader = new BadReader();
System.out.println("badReader.isSuccessfulRead() = " + badReader.isSuccessfulRead());
try { badReader.doSomething(); }
catch(Throwable t) { System.out.println(t); }
System.out.println("badReader.isSuccessfulRead() = " + badReader.isSuccessfulRead());
}
}
Now you can use the two-stage compilation approach.
Console output:
badReader.isSuccessfulRead() = true
execution(void com.BadReader.doSomething()) - calling 'fail()' before rethrowing error
java.lang.RuntimeException: my error
badReader.isSuccessfulRead() = false
The problem is due to the two-step compilation. During the second step, ajc needs the source code of SafeReaderIMPL to be able to weave BadReader, but it cannot find it into aspectLib.jar
In fact, if you try compiling in a single step (I did), it compiles and runs.
Unfortunately I don't know a way to fix this without providing the source code during the second compile step, which I suppose would render the whole two-step approach a bit pointless.
I am working in Scout and need SmartField. For this I need to set up lookup for suggestions.
I see the example with creating Lookup Call and than implement in Lookup Service getConfiguredSqlSelect
but I use Hibernate to work with classes, so my question is how to connect Smart field with Hibernate object filled service?
create a new lookup call according to [1] with the following differences:
don't select AbstractSqlLookupService as a lookup servic super type, but AbstractLookupService
in the associated lookup service you now need to implement getDataByAll, getDataByKey, and getDataByText
to illustrate the following snippet should help:
public class TeamLookupService extends AbstractLookupService<String> implements ITeamLookupService {
private List<ILookupRow<String>> m_values = new ArrayList<>();
public TeamLookupService() {
m_values.add(new LookupRow<String>("CRC", "Costa Rica"));
m_values.add(new LookupRow<String>("HON", "Honduras"));
m_values.add(new LookupRow<String>("MEX", "Mexico"));
m_values.add(new LookupRow<String>("USA", "USA"));
}
#Override
public List<? extends ILookupRow<String>> getDataByAll(ILookupCall<String> call) throws ProcessingException {
return m_values;
}
#Override
public List<? extends ILookupRow<String>> getDataByKey(ILookupCall<String> call) throws ProcessingException {
List<ILookupRow<String>> result = new ArrayList<>();
for (ILookupRow<String> row : m_values) {
if (row.getKey().equals(call.getKey())) {
result.add(row);
}
}
return result;
}
...
[1] https://wiki.eclipse.org/Scout/Tutorial/4.0/Minicrm/Lookup_Calls_and_Lookup_Services#Create_Company_Lookup_Call
I have the following code with a simple class and a method for writing and then reading:
ObjectMapper mapper = new ObjectMapper();
try{
DataStore testOut = new DataStore();
DataStore.Checklist ch1 = testOut.addChecklist();
ch1.SetTitle("Checklist1");
String output = mapper.writeValueAsString(testOut);
JsonNode rootNode = mapper.readValue(output, JsonNode.class);
Map<String,Object> userData = mapper.readValue(output, Map.class);
}
public class DataStore {
public static class Checklist
{
public Checklist()
{
}
private String _title;
public String GetTitle()
{
return _title;
}
public void SetTitle(String title)
{
_title = title;
}
}
//Checklists
private Vector<Checklist> _checklists = new Vector<Checklist>();
public Checklist addChecklist()
{
Checklist ch = new Checklist();
ch.SetTitle("New Checklist");
_checklists.add(ch);
return ch;
}
public Vector<Checklist> getChecklists()
{
return _checklists;
}
public void setChecklists(Vector<Checklist> checklists)
{
_checklists = checklists;
}
}
The line:
String output = mapper.writeValueAsString(testOut);
causes an exception that has had me baffled for hours and about to abandon using this at all.
Any hints are appreciated.
Here is the exception:
No serializer found for class DataStore$Checklist and no properties discovered to create BeanSerializer (to avoid exception, disable SerializationConfig.Feature.FAIL_ON_EMPTY_BEANS) ) (through reference chain: DataStore["checklists"]->java.util.Vector[0])
There are multiple ways to do it, but I will start with what you are doing wrong: your naming of getter and setter method is wrong -- in Java one uses "camel-case", so you should be using "getTitle". Because of this, properties are not found.
Besides renaming methods to use Java-style names, there are alternatives:
You can use annotation JsonProperty("title") for GetTitle(), so that property is recognized
If you don't want the wrapper object, you could alternatively just add #JsonValue for GetTitle(), in which case value used for the whole object would be return value of that method.
The answer seems to be: You can't do that with Json. I've seen comments in the Gson tutorial as well, that state that some serialization just doesn't work. I downloaded XStream and spat it out with XML in a few minutes of work and a lot less construction around what I really wanted to persist. In the process, I was able to delete a lot of code.
The following TestNG (6.3) test case generates the error "Invalid context for the recording of expectations"
#Listeners({ Initializer.class })
public final class ClassUnderTestTest {
private ClassUnderTest cut;
#SuppressWarnings("unused")
#BeforeMethod
private void initialise() {
cut = new ClassUnderTest();
}
#Test
public void doSomething() {
new Expectations() {
MockedClass tmc;
{
tmc.doMethod("Hello"); result = "Hello";
}
};
String result = cut.doSomething();
assertEquals(result, "Hello");
}
}
The class under test is below.
public class ClassUnderTest {
MockedClass service = new MockedClass();
MockedInterface ifce = new MockedInterfaceImpl();
public String doSomething() {
return (String) service.doMethod("Hello");
}
public String doSomethingElse() {
return (String) ifce.testMethod("Hello again");
}
}
I am making the assumption that because I am using the #Listeners annotation that I do not require the javaagent command line argument. This assumption may be wrong....
Can anyone point out what I have missed?
The JMockit-TestNG Initializer must run once for the whole test run, so using #Listeners on individual test classes won't work.
Instead, simply upgrade to JMockit 0.999.11, which works transparently with TestNG 6.2+, without any need to specify a listener or the -javaagent parameter (unless running on JDK 1.5).