What does the program do? How can the program be fixed? How could the program be improved?

This is the code:

public class BigMain {

public static void main(String[] args) {

String secret = "jihgfedcba9yxwvutsrqponmlk";

String clear = "";

for(int i = secret.length() - 1; i >= 0; i--) {

char c = secret.charAt(i);

int newPosition = Character.getNumericValue(c) - 9;

newPosition = (newPosition - 10);

if(newPosition <= 0) {

newPosition += 26;

}

clear = clear + Character.forDigit(newPosition + 9, 36);

}

// clear should read 'abcdefghijklmnopqrstuvwxyz'

System.out.println("'" + secret + "' equates to ... " + clear);

secret = "im9cyxoosqrd";

clear = "";

for(int i = secret.length() - 1; i >= 0; i--) {

char c = secret.charAt(i);

int newPosition = Character.getNumericValue(c) - 9;

newPosition = (newPosition - 10);

if(newPosition <= 0) {

newPosition += 26;

}

clear = clear + Character.forDigit(newPosition + 9, 36);

}

// clear should read 'cpsoneeighty'

System.out.println("'" + secret + "' equates to ... " + clear);

}

}

This is secret1.txt:

ynivnodko9obogdkrgobkog

dmkxkdyxcsomxovvomho

dslkrkcsds

deyqxsfsvkoukwog

ynogdkrgpy

deyopsvkoukwog

ofsqogdkrgpy

This is secret2.txt:

nbycockbobo

ofsyvodckbolve

csmkxnomynowocckqo

erygklyediy

im9cyxoosqrd