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javadroolsoptaplanner

Drools claims that method was overloaded

I have a class MyClass that has a method getId() with return type Long. I am using it with optaplanner. I create a solver factory from a resource file and build a solver.

SolverFactory solverFactory = SolverFactory.createFromXmlResource("/path/to/config");
Solver solve = solverFactory.buildSolver();

When buildSolver() is executed, I see the warning

Getter overloading detected in class mypackage.MyClass : getId (class java.lang.Object) vs getId (class java.lang.Long)

I am wondering where optaplanner finds the method getId() with return type Object. It is nowhere in the source code!

EDIT

As pointed out in the comments, the warning could also mean, that drools has found two methods: getId(Object) and getId(Long). This is even more suspicious, since I did not define a getId method that takes any parameters.

UPDATE

I have investigated the class https://github.com/kiegroup/drools/blob/master/drools-core/src/main/java/org/drools/core/util/asm/ClassFieldInspector.java in the version that I have on my machine using the maven dependency 

<dependency>
  <groupId>org.optaplanner</groupId>
  <artifactId>optaplanner-benchmark</artifactId>
  <version>6.4.0.Final</version>
</dependency>

When the ClassFieldInspector is instanciated with classUnderInspection equals "mypackage.MyClass", then the list of methods

final List<Method> methods = Arrays.asList( clazz.getMethods() );

does indeed contain two methods called getId():

  1. "public java.lang.Long mypackage.myClass.getId()"
  2. "public java.lang.Object mypackage.myClass.getId()"
Solution

  • The problem was caused by the fact that MyClass implements a generic interface that declares the method getId. I have posted this as a separate question

    Implementing generic java interface adds additional method

    because of its general nature not related to optaplanner.