Помогите разобраться
package com.javarush.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.HashMap;
import java.util.Map;
public class Solution {
public static void main(String[] args) throws IOException {
//add your code here
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
URL url = new URL(br.readLine());
String s = url.toString();
String[] paramsUrl = s.split("\\?");
String[] params = paramsUrl[1].split("&");
HashMap<String,String> map = new HashMap<>();
for (String param : params) {
if (param.contains("="))
{
String name = param.split("=")[0];
String value = param.split("=")[1];
map.put(name, value);
}
else
{
String name = param;
String value = null;
map.put(name, value);
}
}
for (Map.Entry<String,String> entry : map.entrySet())
{
System.out.print(entry.getKey());
System.out.print(" ");
}
for (Map.Entry<String,String> entry : map.entrySet())
{
if (entry.getKey().equals("obj")){
try{
System.out.println();
alert(Double.parseDouble(entry.getValue()));
} catch (NumberFormatException e) {
System.out.println();
alert(entry.getValue());
}
}
}
}
public static void alert(double value) {
System.out.println("double: " + value);
}
public static void alert(String value) {
System.out.println("String: " + value);
}
}