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Hi there, I've been dealing with this task for two days and the fact is that I think I don't understand what's expected in this task and why my solution has not been validated. Some help please?

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.util.StringTokenizer; /* Request parser */ public class Solution { public static void main(String[] args) throws IOException { //write your code here //String line = "http://codegym.cc/alpha/index.html?test=hoho&test2=haha&test3&obj=3.14&nameWithoutVal"; BufferedReader reader = new BufferedReader(new InputStreamReader(System.in)); String URL = ""; try { URL = reader.readLine(); }catch(IOException e){ System.out.println(e.getCause()); } String paramPart = ""; String paramObj = ""; for (String parameter : URL.split("\\?")[1].split("&")) { if(paramPart.length()==0) { paramPart = parameter.split("=")[0] + " "; } else { paramPart = paramPart + parameter.split("=")[0] + " "; } if(parameter.split("=").length>1 && parameter.split("=")[1]!="") { if(paramObj.length()==0) { paramObj = parameter.split("=")[1] + " "; }else { paramObj = paramObj + parameter.split("=")[1] + " "; } } } System.out.println(paramPart); //System.out.println(paramObj); StringTokenizer stringTokenizer = new StringTokenizer(paramObj, " "); while (stringTokenizer.hasMoreTokens()) { String nextToken = stringTokenizer.nextToken(); if(nextToken.contains(".")) { try { alert(Double.parseDouble(nextToken)); }catch(NumberFormatException e) { alert(nextToken); } } else { alert(nextToken); } } } 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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LuisRC

Level 39 , Gijón, Spain

19 February 2022, 09:17

Thanks for your expertise. I think that in this task the main issue was not understanding what it was about (perhaps I would have needed a better english level) and of course not having knowledge enough about java strings. I have to confess that I was not able to fully complete this task and for sure I would have to go over it.

Guadalupe Gagnon

Level 37 , Tampa, United States

18 February 2022, 20:38

The problem is that the code should only output an "alert" when the parameter specifically equals "obj". This code sends every value when there is something to the right of the equals sign. For example, in the test line that you have commented out, the correct output would be: test test2 test3 obj nameWithoutVal double: 3.14 Fix this and your code will pass Some tips: Simplifying code makes it a LOT easier to work with. In this case I have a few suggestions - splitting "parameter" and saving the result in a String[] to use later, since you call the split method multiple times, will clean things up. Example starting between lines 27 and 28:

String[] split = parameter.split("="); // create a variable to store result use in later parts of code
if(paramPart.length()==0)
   paramPart = split[0] + " ";
else
   paramPart = paramPart + split[0] + " ";

if(split.length > 1 &&split[1]!="")
   if(paramObj.length()==0)
      paramObj =split[1] + " ";
   else
      paramObj = paramObj + split[1] + " ";

- Next I wouldn't worry about formatting the paramObj String that you are building because it is not used for anything other than send values to the alert method, so just simply:

if(split.length > 1 &&split[1]!="")
   paramObj = paramObj + split[1] + " ";