Works when testing, please help

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Not sure what they want, works with both examples if I hardcode them as URL's. Requirements specifications SUCK for THIS task....

Read a URL from the console.
Display a space-delimited list of all the parameters (The parameters follow the "?" and are separated by "&", e.g. "lvl=15").
The URL contains at least 1 parameter.
The parameters must be displayed in the same order in which they are present in the URL.
If the obj parameter is present, pass its value to the relevant alert method.
alert(double value) - for numbers (fractional numbers have a decimal point)
alert(String value) - for strings
Note that the alert method must be called AFTER the list of all parameters is displayed.

Example 1

Input:
http://codegym.cc/alpha/index.html?lvl=15&view&name=Amigo

Output:
lvl view name

Example 2

Input:
http://codegym.cc/alpha/index.html?obj=3.14&name=Amigo

Output:
obj name double: 3.14

Requirements:

The program should read only one line from the keyboard.
The Solution class must not have static fields.
The program must display data on the screen in accordance with the task conditions.
The program should call the alert method with the double parameter if the obj parameter can be correctly converted to a double.
The program should call the alert method with the String parameter if the obj parameter CANNOT be correctly converted to a double.

package com.codegym.task.task15.task1527; import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; import java.net.URL; import java.util.ArrayList; import java.util.LinkedHashMap; import java.util.List; import java.util.Map; /* Request parser */ public class Solution { public static void main(String[] args) throws IOException { BufferedReader reader = new BufferedReader(new InputStreamReader(System.in)); String URL = reader.readLine(); //String URL = "http://codegym.cc/alpha/index.html?obj=3.14&name=Amigo"; String[] myStrArray = URL.split("[?&]"); ArrayList<String> pList = new ArrayList<>(); for (String line : myStrArray) { if (line.contains("=")) pList.add(line.substring(0, line.indexOf('='))); if (!line.contains("http://") && !line.contains("=")) pList.add(line); } for (String param : pList) System.out.print(param + " "); System.out.println(); String[] myStrArray2 = null; for (String line : myStrArray) { myStrArray2 = (line.split("[=]")); for (String line2 : myStrArray2) { if ((line2.contains("."))&& (!line2.contains("http"))){ try { double d = Double.parseDouble(line2.substring(line2.indexOf('=') + 1)); alert(d); break; } catch (Exception e) { String str = line2.substring(line2.indexOf('=') + 1); alert(str); break; } } } } } public static void alert(double value) { System.out.println("double: " + value); } public static void alert(String value) { System.out.println("String: " + value); } }

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Guadalupe Gagnon

Level 37 , Tampa, United States

28 May 2019, 14:34

Using hard code is how i test everything, entering user input every single time is such a pain in the rear. Anyways. The big problem that I see with your code is that it does not output: String: *yadayadayada* This is because when obj = stringVal the if statements are going to pre-throw it out, specifically (line2.contains("."). I would change line 23 to split first by "?", which will split the url by ["stuff you dont need", "stuff you do need"], then do second split of the stuff you do need by "&", example:

String[] tempSplit = URL.split("[?]")[1].split(";
String[] stuffYouNeed= URL.split("&");

or you can get fancy and do it this way:

String[] myStrArray = URL.split("[?]");
myStrArray = myStrArray[1].split("&");

or get REAL fancy and do it this way:

String[] myStrArray = URL.split("[?]")[1].split("&");

Then you know every thing is a parameter. This would only need a couple modifications of the code you already wrote.

Henk

Level 19 , Pretoria, South-Africa

29 May 2019, 09:04

what does the [1] do ? I tried using an Arraylist to manually move to different occurances in an array, but it didn't want to compile. Obviously I don't understand "URL parameters", yet... But also, what do they mean with "object parameter" ? Is it a naming convention for a part of a URL, or is it the literal "object" which only they use in their URL's ?

Guadalupe Gagnon

Level 37 , Tampa, United States

29 May 2019, 13:18

useful

Don't think of it as a URL, its a string. This whole task is just practice with String manipulation. Those three lines of code I put are all identical. The first one (a typo is in there btw, first line should be String[] tempSplit = URL.split("[?]")) splits the string by the question mark. If you notice the example, on the right side of the question mark (?) is trash, on the left side is all the parameters for the task, so you end up with a 2 element Array... [0 - *stuff you don't need*, 1 - *stuff you do need*]. The second line splits the second element (which is element 1) by the ampersand (&), which give you a nice array of only the parameters. So all three lines do exactly what I described above, but are written differently. The first uses 2 separate arrays, the second uses only 1 array but does these steps on 2 lines, the third uses 1 array but does all the steps on one line.

Radosław Dziura

Level 16

23 May 2020, 17:53

I just want to ask, why do we have a question mark inside square brackets? Can't we do it like this? String[] tempSplit = URL.split("\\?")) (quite frankly i don't understand why there are two backslashes inside this bracket, I would be really greatful if you could answer it as well.

Henk

Level 19 , Pretoria, South-Africa

28 May 2019, 10:44

Also, in IntellijIDEA, if I run it and try to enter a URL in the console window, it actually opens the webpage, instead of using it in the Java program........I probably need to do that differently, lol ?