Find all substrings of a string - StringIndexOutOfBoundsException
- by nazar_art
I created class Word. Word has a constructor that takes a string argument and one method getSubstrings which returns a String containing all substring of word, sorted by length.
For example, if the user provides the input "rum", the method returns a
string that will print like this:
r
u
m
ru
um
rum
I want to concatenate the substrings in a String, separating them with a newline ("\n"). Then return the string.
Code:
public class Word {
String word;
public Word(String word) {
this.word = word;
}
/**
* Gets all the substrings of this Word.
* @return all substrings of this Word separated by newline
*/
public String getSubstrings()
{
String str = "";
int i, j;
for (i = 0; i < word.length(); i++) {
for (j = 0; j < word.length(); j++) {
str = word.substring(i, i + j);
str += "\n";
}
}
return str;
}
But it throws exception:
java.lang.StringIndexOutOfBoundsException: String index out of range: -1
at java.lang.String.substring(String.java:1911)
I stuck at this point. Maybe, you have other suggestions according this method signature public String getSubstrings().
How to solve this issue?
