optaplanner-core/src/main/java/org/optaplanner/core/impl/solver/termination/PhaseToSolverTerminationBridge.java
@Override
    public Termination createChildThreadTermination(
            DefaultSolverScope solverScope, ChildThreadType childThreadType) {
        if (childThreadType == ChildThreadType.PART_THREAD) {
            // Remove of the bridge (which is nested if there's a phase termination), PhaseConfig will add it again
            return solverTermination.createChildThreadTermination(solverScope, childThreadType);
        } else {
            throw new IllegalStateException("The childThreadType (" + childThreadType + ") is not implemented.");
        }
    }
@Override
    public Termination createChildThreadTermination(
            DefaultSolverScope solverScope, ChildThreadType childThreadType) {
        if (childThreadType == ChildThreadType.PART_THREAD) {
            // Remove of the bridge (which is nested if there's a phase termination), PhaseConfig will add it again
            return solverTermination.createChildThreadTermination(solverScope, childThreadType);
        } else {
            throw new IllegalStateException("The childThreadType (" + childThreadType + ") is not implemented.");
        }
    }
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