What is wrong?

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Hi. Hi. What is wrong? Validator is impermeable: The getQuery method must return a string built according to the rules specified in the task conditions. Be sure that the getQuery method works correctly if the passed Map has null values. I check if params is null if it's going out. I set up all the possibilities and testing is ok. I don't know what's validation now? Suggestions?? Thanks:)

Build part of a WHERE query using StringBuilder.
If a parameter is null, then it shouldn't be included in the query.

Example:

{name=Johnson, country=United States, city=Los Angeles, age=null}

Result:

name = 'Johnson' and country = 'United States' and city = 'Los Angeles'

Requirements:

The getQuery method must have one Map parameter.
The getQuery method must return a String.
The getQuery method must be static.
The getQuery method must return a string built according to the rules specified in the task conditions.

package com.codegym.task.task22.task2208; import java.util.*; /* Build a WHERE query */ public class Solution { public static void main(String[] args) { Map<String, String> dane= new LinkedHashMap<>(); dane.put("name", "Johnson"); dane.put("country", "United States"); dane.put("city", "Los Angeles"); dane.put("age", null); //dane.put("sex", "men"); //dane.put("nationality", "Polish"); System.out.println(getQuery(dane)); } public static String getQuery(Map<String, String> params) { if (params == null) { return ""; } StringBuilder endStr = new StringBuilder(); int size = 0; String format = "%s = '%s'"; for (Map.Entry<String, String> pair : params.entrySet()) { if (pair.getKey() != null && pair.getValue() != null) { if(size < params.size() -1) { endStr.append(String.format(format, pair.getKey(), pair.getValue()) + " and "); size++; } else if(size == params.size() -1) { endStr.append(String.format(format, pair.getKey(), pair.getValue())); } } else if(pair.getValue() == null) { endStr.delete(endStr.length()-5,endStr.length()); break; } else if (pair.getKey() == null && pair.getValue() == null) { endStr.delete(endStr.length()-5,endStr.length()); break; } else if (pair.getKey() == null && pair.getValue() != null) { endStr.delete(endStr.length()-5,endStr.length()); break; } } return endStr.toString(); } }

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Darek

Level 41 , Katowice, Poland

15 July 2020, 14:08

The content of the task was only: "dane.put (" name "," Johnson "); dane.put (null, "United States"); dane.put ("city", "Los Angeles"); dane.put ("age", null); " I added other data to check different cases. During testing everything worked fine for me On all cases. Prints only when key and value are present. When one of the fields is null or both are null, this is omitted. That's how the tests showed me. And under no circumstances does the program stop.

Guadalupe Gagnon

Level 37 , Tampa, United States

15 July 2020, 14:03

It looks like this code stops if a null value is encountered, though it should not do this. The final string should contain all pairs that do not contain a null value. Say if the main method had this:

Map<String, String> dane= new LinkedHashMap<>();
dane.put("name", "Johnson");
dane.put(null, "United States");
dane.put("city", "Los Angeles");
dane.put("age", null);
dane.put("sex", "man");
dane.put("nationality", "Polish");

the output should be along the lines of this: name = 'Johnson' and city = 'Los Angeles' and sex = 'man' and nationality = 'Polish'