Custom Comparator to sort list of states, counties and zip codes

Question

I'm having hard time to write comparator to sort list of custom objects with the following string fields: 1. Branch Class --> Can be state, county or zip code and used to identify which data field is it; can't be empty 2. State --> State Name, can't be empty 3. Geography --> If branch class.equals'county', it will hold the county name, can be empty 4. zip --> zip code. Can be empty for states and counties 5. ParentNodeId --> the name of the parent that should be applicable for this tree. For example, a state has no parent (empty string) while the county has the state as parentNodeId and the zipCode has the county as the parentNodeId. So, for geography object with branch = "state", zipCode "36003", the parentNodeId should be Autauga and state is "AL". For geography object with branch ="county" and geography = "Autauga", then the parentNodeId is "AL".

The current object list is in the form: state - state - state - county - county - zip code - zip code

While I'm looking to have a list of

-state

-- County

-- Zip Code

-- Zip Code

-- County

-- Zip Code

-State

-- County

and so on.

My trial is still missing cases that I'm not aware of. Here's my code

public static final Comparator<Geography> BY_STATE_COUNTY_ZIP_COMPARATOR = new Comparator<Geography>() {

public int compare(final Geography obj1, final Geography obj2) {

    if (obj1.getZip().equals("89420") || obj2.getZip().equals("89420") || obj1.getGeography().equals("Mono")
            || obj2.getGeography().equals("Mono")) {
        System.out.println("hdfhd");
    }

    if (obj1.getBranchClass().equalsIgnoreCase(obj2.getBranchClass())) {
        return this.similarBranchComparison(obj1, obj2);
    }
    else {
        // Different branches
        final int x = this.differentBranchesComparison(obj1, obj2);
        return x;
    }

}

private int differentBranchesComparison(final Geography obj1,
        final Geography obj2) {

    if ((obj1.getZip().equals("89420") && obj1.getParentNodeId().equals("Mono"))
            || ((obj2.getZip().equals("89420") && obj2.getParentNodeId().equals("Mono")))) {
        System.out.println("hdfhd");
    }

    // Same states - Obj1 is state
    if (obj1.getBranchClass().equalsIgnoreCase(ASDGeographyBasedDashboardVO.STATE_LEVEL)
            && obj1.getState().equalsIgnoreCase(obj2.getState())) {
        // obj2 should be greater
        return -1;
    }
    // Same states - Obj2 is state
    else if (obj2.getBranchClass().equalsIgnoreCase(ASDGeographyBasedDashboardVO.STATE_LEVEL)
            && obj1.getState().equalsIgnoreCase(obj2.getState())) {
        // obj1 should be greater
        return 1;
    }
    // Different states - obj1 OR Obj2 is state
    else if (((obj1.getBranchClass().equalsIgnoreCase(ASDGeographyBasedDashboardVO.STATE_LEVEL)) || (obj2
            .getBranchClass().equalsIgnoreCase(ASDGeographyBasedDashboardVO.STATE_LEVEL)))
            && !(obj1.getState().equalsIgnoreCase(obj2.getState()))) {
        // Delegate to state comparison
        return new CompareToBuilder().append(obj1.getState(), obj2.getState()).toComparison();
    }
    // Same states - Same counties (County - Zip)
    else if (obj1.getBranchClass().equalsIgnoreCase(ASDGeographyBasedDashboardVO.COUNTY_LEVEL)
            && ((obj1.getState().equalsIgnoreCase(obj2.getState())) && (obj1.getGeography()
                    .equalsIgnoreCase(obj2.getParentNodeId())))) {
        // obj2 (zip) should be greater
        return -1;
    }
    // Same states - Same counties (Zip - County)
    else if (obj2.getBranchClass().equalsIgnoreCase(ASDGeographyBasedDashboardVO.COUNTY_LEVEL)
            && ((obj1.getState().equalsIgnoreCase(obj2.getState())) && (obj1.getParentNodeId()
                    .equalsIgnoreCase(obj2.getGeography())))) {
        // obj1 should be greater
        return 1;
    }
    // Same states different counties (County - zip)
    else if ((obj1.getBranchClass().equalsIgnoreCase(ASDGeographyBasedDashboardVO.COUNTY_LEVEL))
            && (obj1.getState().equalsIgnoreCase(obj2.getState()) && !(obj1.getGeography()
                    .equalsIgnoreCase(obj2.getParentNodeId())))) {
        return new CompareToBuilder().append(obj1.getGeography(), obj2.getParentNodeId()).toComparison();
    }

    // Same states different counties (Zip - County)
    else if ((obj2.getBranchClass().equalsIgnoreCase(ASDGeographyBasedDashboardVO.COUNTY_LEVEL))
            && (obj1.getState().equalsIgnoreCase(obj2.getState()) && !(obj1.getParentNodeId()
                    .equalsIgnoreCase(obj2.getGeography())))) {
        return new CompareToBuilder().append(obj1.getParentNodeId(), obj2.getGeography()).toComparison();
    }

    // Different States
    else if (((obj1.getBranchClass().equalsIgnoreCase(ASDGeographyBasedDashboardVO.COUNTY_LEVEL)) || (obj2
            .getBranchClass().equalsIgnoreCase(ASDGeographyBasedDashboardVO.COUNTY_LEVEL)))
            && !(obj1.getState().equalsIgnoreCase(obj2.getState()))) {
        return new CompareToBuilder().append(obj1.getState(), obj2.getState()).toComparison();
    }
    return 0;

}

private int similarBranchComparison(final Geography obj1,
        final Geography obj2) {
    // State-State, County - County, Zip-Zip
    // State-State
    if (obj1.getBranchClass().equalsIgnoreCase(ASDGeographyBasedDashboardVO.STATE_LEVEL)) {
        return new CompareToBuilder().append(obj1.getState(), obj2.getState()).toComparison();
    }
    // County - County
    else if (obj1.getBranchClass().equalsIgnoreCase(ASDGeographyBasedDashboardVO.COUNTY_LEVEL)) {
        if (obj1.getState().equalsIgnoreCase(obj2.getState())) {
            // Compare Counties within the same state
            return new CompareToBuilder().append(obj1.getGeography(), obj2.getGeography()).toComparison();
        }
        else {
            // Compare Counties within different states
            return new CompareToBuilder().append(obj1.getState(), obj2.getState()).toComparison();
        }
    }
    else {
        // Zip - Zip
        if (obj1.getState().equalsIgnoreCase(obj2.getState())) {
            if (obj1.getParentNodeId().equalsIgnoreCase(obj2.getParentNodeId())) {
                return new CompareToBuilder().append(obj1.getZip(), obj2.getZip()).toComparison();
            }
            else {
                return new CompareToBuilder().append(obj1.getParentNodeId(), obj2.getParentNodeId())
                        .toComparison();
            }
        }
        else {
            // Compare Zip codes within different states
            return new CompareToBuilder().append(obj1.getState(), obj2.getState()).toComparison();
        }

    }
}
};

Answer 1

This should a simple comparator where you first compare state, then county, then zip. So this assumes you can write getState(), getCounty(), and getZip() methods, and you can write a compare for state, county, and zip. If you cannot get the state from all the different types, then you cannot compare them.

Here's some pseudo-code.

Comparator<Geography> comparator = new Comparator<>() {
    public int compare(final Geography obj1, final Geography obj2) {
        state1 = getState(obj1);
        state2 = getState(obj2);

        int retCode = state1.compare(state2);
        if (retCode != 0)
            return retCode;

        county1 = getCounty(obj1);
        county2 = getCounty(obj2);

        retCode = county1.compare(county2);
        if(retCode != 0)
           return retCode;

        zip1 = getZip(obj1);
        zip2 = getZip(obj2);

        retCode = zip1.compare(zip2);
        return retCode;
   }
}