Please help my brain is getting puzzled

Question about the task

Request parser

Java Core, Level 5, Lesson 12

Under discussion

What part to rectify ?

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.ArrayList; /* Request parser */ public class Solution { public static void main(String[] args) throws Exception { BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); String URL = br.readLine(); String split1[] = URL.split("\\?"); String split2[] = split1[1].split("&"); // String split3[] = split2[1].split("="); ArrayList<String> list = new ArrayList<>(); ArrayList<String> listObject = new ArrayList<>(); String[] splitstore; for (int i = 0; i < split2.length; i++) { if (split2[i].contains("=")) { splitstore = split2[i].split("="); if (splitstore[0].equals("obj")) { list.add(splitstore[0]); listObject.add(splitstore[1]); } else { listObject.add(splitstore[0]); list.add(splitstore[1]); } } else { list.add(split2[i]); } } for (String i : listObject ) { try { double y = Double.parseDouble(i); alert(y); } catch (Exception e) { System.out.println(e); } } } public static void alert(double value) { System.out.println("double: " + value); } public static void alert(String value) { System.out.println("obj " + value); } }

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Patryk

Level 24 , Warsaw, Poland

25 December 2019, 16:55

Line 35, whole else block is useless and wrong. In catch block you should use alert method (with String parameter), in case you cannot parse i (String) to Double, because you add value (in if block, line 30) to listObject only if you parameter is "obj"

Patryk

Level 24 , Warsaw, Poland

25 December 2019, 16:54

Example

public class Solution {

    public static void main(String[] args) {
        //write your code here

        List<String> parameters = new ArrayList<>();
        List<String> parametersValue = new ArrayList<>();

        String inputUrl = readURL();
        parseURL(inputUrl, parameters, parametersValue);
        print(parameters);
        useAlert(parametersValue);

    }

    public static String readURL() {
        Scanner scanner = new Scanner(System.in);
        return scanner.nextLine();
    }

    public static void parseURL(String inputURL, List<String> parameters, List<String> parametersValue) {

        String[] array = inputURL.split("\\?");
        if (array.length == 2) {
            String toParse = array[1];
            String[] afterFirstParse = toParse.split("&");
            for (int i = 0; i < afterFirstParse.length; i++) {
                if (afterFirstParse[i].contains("=")) {
                    String[] parsed = afterFirstParse[i].split("=");
                    parameters.add(parsed[0]);
                    if (parsed[0].equals("obj")) {
                        parametersValue.add(parsed[1]);
                    }
                } else parameters.add(afterFirstParse[i]);
            }
        } else System.out.println("Sth wrong");
    }

    public static void print(List<String> list) {
        for (String x : list) {
            System.out.print(x + " ");
        }
    }

    public static void useAlert(List<String> list) {
        System.out.println();
        for (String x : list) {
            try {
                alert(Double.parseDouble(x));
            } catch (Exception e) {
                alert(x);
            }
        }
    }

    public static void alert(double value) {
        System.out.println("double: " + value);
    }

    public static void alert(String value) {
        System.out.println("String: " + value);
    }

Peter Gray

Level 20 , Compiegne, France

21 May 2020, 22:44

Thanks, mate. The over-complication and general lack of sense (not mentioning the task description) were dreadful in this task.