optaplanner-examples/src/main/java/org/optaplanner/examples/machinereassignment/solver/drools/MrMachineTransientUsage.java
@Override
    public int compareTo(MrMachineTransientUsage other) {
        return new CompareToBuilder()
                .append(machineCapacity, other.machineCapacity)
                .append(usage, other.usage)
                .toComparison();
    }
@Override
    public int compareTo(MrMachineTransientUsage other) {
        return new CompareToBuilder()
                .append(machineCapacity, other.machineCapacity)
                .append(usage, other.usage)
                .toComparison();
    }
Used by the GUI to sort the {@link ConstraintMatch} list
by {@link ConstraintMatch#getJustificationList()}.
@param other never null
@return comparison