I've tested with numerous strings of different lengths and different numbers of spaces, empty string, null. All of them either produce a substring that matches the requirement (with no leading or trailing spaces), or throws the required exception.
There is one situation where the conditions aren't clear. Consider the following string :
System.out.println(getPartOfString("CodeGym is the best "));"is the best "package com.codegym.task.task22.task2202;
/*
Find a substring
*/
public class Solution
{
public static void main(String[] args) throws StringTooShortException
{
System.out.println(getPartOfString("CodeGym is the best "));
//System.out.println(getPartOfString("CodeGym is the best place"));
//System.out.println(getPartOfString("CodeGym"));
//System.out.println(getPartOfString(""));
//System.out.println(getPartOfString(null));
}
public static String getPartOfString(String string) throws StringTooShortException
{
if(string == null)
{
throw new StringTooShortException();
}
String output = null;
int firstSpace = string.indexOf(" ");
int fourthSpace = 0;
int spaceCount = 0;
for (int i = 0; i < string.length(); i++)
{
if (string.charAt(i) == ' ')
{
spaceCount++;
}
if (spaceCount == 4)
{
fourthSpace = i;
break;
}
}
if(spaceCount < 4)
{
throw new StringTooShortException();
}
String fifthWord = "";
for (int i = fourthSpace + 1; i < string.length(); i++)
{
if (Character.isLetter(string.charAt(i)))
{
fifthWord += string.charAt(i);
}
else
{
break;
}
}
if(fifthWord.length() == 0)
{
throw new StringTooShortException();
}
output = string.substring(firstSpace + 1, fourthSpace + fifthWord.length() +1);
return output;
}
public static class StringTooShortException extends RuntimeException
{
public StringTooShortException()
{
super();
}
}
}