I keep getting this error when i try to test this part of my program....

Im trying to make this (below) happen and test it using the tester given-------------------------------------------------------------------------

Encrypts a string according the Bellaso Cipher. Each character in plainText is offset

* according to the ASCII value of the corresponding character in bellasoStr, which is repeated

* to correspond to the length of plainText

* @param plainText an uppercase string to be encrypted.

* @param bellasoStr an uppercase string that specifies the offsets, character by character.

* @return the encrypted string

-------------------------------------------------------------------------------------

THE ERROR IS (below)

Exception in thread "main" java.lang.StringIndexOutOfBoundsException: begin 0, end 13, length 7

at java.base/java.lang.String.checkBoundsBeginEnd(Unknown Source)

at java.base/java.lang.String.substring(Unknown Source)

at CryptoManager.encryptBellaso(CryptoManager.java:91)

at CryptoTest.main(CryptoTest.java:21)

The testing unit im using is below---------------------------------------------------------------------------------

public class CryptoTest {

public static void main(String[] args) {

String str1 = "\"THIS TEST SHOULD SUCCEED\"";

String str2 = "\"THIS TEST THAT SHOULD FAIL BECAUSE { IS OUTSIDE THE RANGE\"";

String str3 = "\"This test should fail because of lowercase letters\"";

String str4 = "THIS IS ANOTHER TEST";

String bellasoStr = "CMSC203";

String str5 = "WKLV#LV#DQRWKHU#WHVW";

String str6 = "WU\\VR9F#N!RF88U-'HED";

boolean good = CryptoManager.stringInBounds(str1);

boolean bad = CryptoManager.stringInBounds(str2);

System.out.println(str1+" Is it in bounds? "+good);

System.out.println(str2+" Is it in bounds? "+bad);

bad = CryptoManager.stringInBounds(str3);

System.out.println(str3+" Is it in bounds? "+bad);

System.out.println("Caesar cipher of \""+str4+"\" should return \"WKLV#LV#DQRWKHU#WHVW\": "+ CryptoManager.encryptCaesar(str4, 3));

System.out.println("Bellaso cipher of \""+str4+"\" should return \"WU\\VR9F#N!RF88U-'HED\": "+ CryptoManager.encryptBellaso(str4, bellasoStr));

System.out.println("Caesar decryption of \""+str5+"\" should return \"THIS IS ANOTHER TEST\": "+ CryptoManager.decryptCaesar(str5, 3));

System.out.println("Bellaso decryption of \""+str6+"\" should return \"THIS IS ANOTHER TEST\": "+ CryptoManager.decryptBellaso(str6, bellasoStr));

}

}

ANd this is the part causing the problem-----------------------------------------------------------------------------

.....

private static final char LOWER_BOUND = ' ';

private static final char UPPER_BOUND = '_';

private static final int RANGE = UPPER_BOUND - LOWER_BOUND + 1;

public static String encryptBellaso(String plainText, String bellasoStr) {

//encrypted text

String res="";

//Adjust length of bellasoStr to plainText

while(bellasoStr.length()

{

bellasoStr+=bellasoStr.substring(0,(plainText.length()-bellasoStr.length()));

}

//encryption

for(int i=0;i

{

char c=(char)Wrap_around((int)plainText.charAt(i)+(int)bellasoStr.charAt(i) );

res+=Character.toString(c);

}

//return result

return res;

}