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javaregexurlstring-parsing

How to extract variables from url query to readable format in java?


I have this url:

http://myhost.com/Request?to=s%3A73746647+d%3Afalse+f%3A-1.0+x%3A-74.454383+y%3A40.843021+r%3A-1.0+cd%3A-1.0+fn%3A-1+tn%3A-1+bd%3Atrue+st%3ACampus%7EDr&returnGeometries=true&nPaths=1&returnClientIds=true&returnInstructions=true&hour=12+00&from=s%3A-1+d%3Afalse+f%3A-1.0+x%3A-74.241765+y%3A40.830182+r%3A-1.0+cd%3A-1.0+fn%3A56481485+tn%3A26459042+bd%3Afalse+st%3AClaremont%7EAve&sameResultType=true

how can I extract the from and to arguments in a readable manner?

I have tried the following:

String patternString1 = "(&to=) (.+?) (&returnGeometries) (.+?) (&hour=)"
                        +" (.+?) (&from=) (.+?) (&sameResultType=)";

Pattern pattern = Pattern.compile(patternString1);
Matcher matcher = pattern.matcher(freshResponse.regression_requestUrl);

while(matcher.find()) {
   System.out.println("found: "+matcher.group(1)+" "+matcher.group(3)+matcher.group(4));
}

Pattern pattern = Pattern.compile(patternString1);
Matcher matcher = pattern.matcher(url);

but even if I succeed fetching the correct substrings, how can I convert them to coordinates which I can use to find this place? (in other words: ..such that the coordinates are clean and ready to be used)


Solution

  • This should do what you want:

    public class DecodeURL {
    
        public static void main(String[] args) throws UnsupportedEncodingException {
            String input = "http://myhost.com/Request?to=s%3A73746647+d%3Afalse+f%3A-1.0+"
                    +"x%3A-74.454383+y%3A40.843021+r%3A-1.0+cd%3A-1.0+fn%3A-1+tn%3A-1+bd%3A"
                    +"true+st%3ACampus%7EDr&returnGeometries=true&nPaths=1&returnClientIds="
                    +"true&returnInstructions=true &hour=12+00&from=s%3A-1+d%3Afalse+f%3A-"
                    +"1.0+x%3A-74.241765+y%3A40.830182+r%3A-1.0+cd%3A-1.0+fn%3A56481485+tn"
                    +"%3A26459042+bd%3Afalse+st%3AClaremont%7EAve&sameResultType=true";
    
            String decoded = java.net.URLDecoder.decode(input, "UTF-8").replace("&", " & ");
            String[] params = {"s","d","f","x","y","r","cd","fn","tn","bd","st"};
    
            System.out.println("Decoded input URL: \n"+decoded);
    
            // Output all FROM arguments
            System.out.println("\nFROM:");
            for (int i = 0; i < params.length; i++) {
                System.out.println(params[i]+" = \t"+findInstance(decoded, "from", params[i]));
            }
    
            // Output all TO arguments
            System.out.println("\nTO:");
            for (int i = 0; i < params.length; i++) {
                System.out.println(params[i]+" = \t"+findInstance(decoded, "to", params[i]));
            }
        }
    
        public static String findInstance(String input, String type, String match) {
            int start = input.indexOf(match+":", input.indexOf(type))+match.length()+1;
            return input.substring(start, input.indexOf(" ", start));       
        }
    }
    

    Output

    Decoded input URL: 
    http://myhost.com/Request?to=s:73746647 d:false f:-1.0 x:-74.454383 y:40.843021 r:-1.0 cd:-1.0 fn:-1 tn:-1 bd:true st:Campus~Dr & returnGeometries=true & nPaths=1 & returnClientIds=true & returnInstructions=true  & hour=12 00 & from=s:-1 d:false f:-1.0 x:-74.241765 y:40.830182 r:-1.0 cd:-1.0 fn:56481485 tn:26459042 bd:false st:Claremont~Ave & sameResultType=true
    
    FROM:
    s =     -1
    d =     false
    f =     -1.0
    x =     -74.241765
    y =     40.830182
    r =     -1.0
    cd =    -1.0
    fn =    56481485
    tn =    26459042
    bd =    false
    st =    Claremont~Ave
    
    TO:
    s =     73746647
    d =     false
    f =     -1.0
    x =     -74.454383
    y =     40.843021
    r =     -1.0
    cd =    -1.0
    fn =    -1
    tn =    -1
    bd =    true
    st =    Campus~Dr
    

    To change the number of output parameters, simply edit the params array. For example, if you have String[] params = {"x","y"}, the program will output the coordinates (x,y) only

    I hope that helps you out. Good luck!