Java - UK postcode validator to US postcode validator

Question

I'm wondering how I can turn my UK postcode validator into a US postcode validator. Currently my program reads postcodes from a text file and validates whether they are valid UK postcodes. This works well but I would like too read in US postcodes instead of UK postcodes and then validate them. Below is my current program.

package postcodesort;

import java.util.*;
import java.util.Queue;
import java.util.TreeSet;
import java.io.File;
import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.util.LinkedList;
import java.util.StringTokenizer;
import java.util.regex.Matcher;
import java.util.regex.Pattern;




public class PostCodeSort 
{
Queue<String> postcodeStack = new LinkedList<String>();

public static void main(String[] args) throws IOException 
{
    FileReader fileReader = null;
    ZipCodeValidator zipCodeValidator = new ZipCodeValidator();

    // Create the FileReader object
    try {
        fileReader = new FileReader("usvalidcodes.txt");
        BufferedReader br = new BufferedReader(fileReader);

        String str;
        while((str = br.readLine()) != null) 
        {
            if(zipCodeValidator.isValid(str)){
                System.out.println(str + " is valid");
            }
            else{
                System.out.println(str + " is not valid");
            }
        }
    }

    catch (IOException ex) 
    {
        // handle exception;
    }

    finally 
    {
        fileReader.close();
    }

}
}

And here is the part of code which does the validating via a regex.

package postcodesort;

import java.util.regex.Matcher;
import java.util.regex.Pattern;

/**
*
* @author ec1312017
*/
public class ZipCodeValidator {
private static String regex = "^[A-Z]{1,2}[0-9R][0-9A-Z]? [0-9][ABD-HJLNP-UW-Z]{2}$";
private static Pattern pattern = Pattern.compile(regex, Pattern.CASE_INSENSITIVE);

public boolean isValid(String zipCode) {
    Matcher matcher = pattern.matcher(zipCode);
    return matcher.matches();
}
}

I have also included a small selection of the data within the text file to be read in.

"01","35005","AL","ADAMSVILLE",86.959727,33.588437,10616,0.002627

"05","72001","AR","ADONA",92.903325,35.046956,494,0.00021

"06","90804","CA","SIGNAL HILL",118.155187,33.782993,36092,0.001213

Any help is appreciated and please feel free to ask any questions.

You'll need to amend the regular expression check to suit the US postal format rather than the UK one. If you post the US format with a few examples, it'll be easier to help you find the right regex to handle it. — Dave, Jun 06 '16 at 17:15
Yes, as Dave says, we need examples. If the ZIP code is only 5 numbers, it is different than if it also includes the extension thing. — Laurel, Jun 06 '16 at 17:16
I've posted some examples of what I'll be reading in. So I want it to read that it has 5 numbers and then it reads the first two numbers. So like this "01","35006","AL". That's all I want read and validated as there are 10,000 entries. — danbb, Jun 06 '16 at 17:21

score 0 · Answer 1 · edited May 23 '17 at 12:34

0

A simple solution is to just change the regex. This question regex for zip-code suggests the regex should be ^\d{5}(?:[-\s]\d{4})?$

So the class looks like this:

public class ZipCodeValidator {

private static String regex = "^\d{5}(?:[-\s]\d{4})?$";
private static Pattern pattern = Pattern.compile(regex, Pattern.CASE_INSENSITIVE);


public boolean isValid(String zipCode) {
    Matcher matcher = pattern.matcher(zipCode);
    return matcher.matches();
}
}

This wouldn't validate against the list of zipcoes you provided but it's a lot simpler to implement :)

edited May 23 '17 at 12:34

Community

1
1

answered Jun 06 '16 at 17:18

Matthew

10,361
5
42
54

Would the regex work for this form of data? "01","35005","AL","ADAMSVILLE",86.959727,33.588437,10616,0.002627. – danbb Jun 06 '16 at 17:24
Ultimately I want the program to read the entry and validate the postcode if it has 5 numbers. In this case it would be "35005"? After it has been validated I would then want to assign that entry to a specific state which will be taken from the first two numbers. In that case "01". But that's for another day :) – danbb Jun 06 '16 at 17:27
How could I validate using my list of zip codes as I don't want to remove 10,000 pieces of data from my list of postcodes. – danbb Jun 06 '16 at 17:33

Joseph Hansen · Answer 2 · 2017-06-27T20:33:34.293

Usually, I would suggest you use a well-established address validating service because parsing and matching addresses is pretty complicated: there are lots of little ways to mess up big.

But, you're use case is really specific: you have lines of data that are always the same and you only want a validator that checks if there is a 5-digit postal code in a specific spot of the line.

So, here I've made an edit to your regex validator code so that it matches the data you say you're getting:

public class ZipCodeValidator {
    private static String regex = "^"\d{2}","\d{5}","\w{2}","[\w ]+",\d*\.?\d*,\d*\.?\d*,\d*,\d*\.?\d*$";
    private static Pattern pattern = Pattern.compile(regex, 
    Pattern.CASE_INSENSITIVE);

    public boolean isValid(String entireLineFromFile) {
        Matcher matcher = pattern.matcher(entireLineFromFile);
        return matcher.matches();
    }
}

You can play with the regex on this example on regexr.com. If you hover over characters in the regular expression, a popup will tell you what each part means.

(Full disclosure: I worked for SmartyStreets, an address validator and autocompletion company.)

Java - UK postcode validator to US postcode validator

2 Answers2