optaplanner-examples/src/main/java/org/optaplanner/examples/machinereassignment/domain/MachineReassignment.java
@ProblemFactCollectionProperty
    private List<MrServiceDependency> getServiceDependencyList() {
        List<MrServiceDependency> serviceDependencyList = new ArrayList<>(serviceList.size() * 5);
        for (MrService service : serviceList) {
            for (MrService toService : service.getToDependencyServiceList()) {
                MrServiceDependency serviceDependency = new MrServiceDependency();
                serviceDependency.setFromService(service);
                serviceDependency.setToService(toService);
                serviceDependencyList.add(serviceDependency);
            }
        }
        return serviceDependencyList;
    }
@ProblemFactCollectionProperty
    private List<MrServiceDependency> getServiceDependencyList() {
        List<MrServiceDependency> serviceDependencyList = new ArrayList<>(serviceList.size() * 5);
        for (MrService service : serviceList) {
            for (MrService toService : service.getToDependencyServiceList()) {
                MrServiceDependency serviceDependency = new MrServiceDependency();
                serviceDependency.setFromService(service);
                serviceDependency.setToService(toService);
                serviceDependencyList.add(serviceDependency);
            }
        }
        return serviceDependencyList;
    }
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