Help with figuring out what to use with this program

Question

I have the code all written. I was given instruction.(number should contain the number of digits as there are eligible characters in word or 7, whichever is less. If number ends up containing more than 3 digits then a hyphen ( - ) should be placed between the third and fourth digits.)
I cant figure out if i use a if and else statement or some other and also how to get the program to print out just the normal 7 digits in a number and forget about the rest if entered.
// Phone.java
// Author:
import java.util.Scanner;
public class Phone{
private String word;
private String number;
public Phone(String wd) {
word = wd;
number = ("");
setNumber();
private void setNumber(){
for (int i = 0; i <= word.length() - 1; i++ )
switch(word.charAt(i))
case 'A':
case 'a':
case 'B':
case 'b':
case 'C':
case 'c': number += "2";
break;
case 'D':
case 'd':
case 'E':
case 'e':
case 'F':
case 'f': number += "3";
break;
case 'G':
case 'g':
case 'H':
case 'h':
case 'I':
case 'i': number += "4";
break;
case 'J':
case 'j':
case 'K':
case 'k':
case 'L':
case 'l': number += "5";
break;
case 'M':
case 'm':
case 'N':
case 'n':
case 'O':
case 'o': number += "6";
break;
case 'P':
case 'p':
case 'R':
case 'r':
case 'S':
case 's': number += "7";
break;
case 'T':
case 't':
case 'U':
case 'u':
case 'V':
case 'v': number += "8";
break;
case 'W':
case 'w':
case 'X':
case 'x':
case 'Y':
case 'y': number += "9";
break;
public String toString(){
return number;
}

Answer 1

adr2488 wrote:
number should contain the number of digits as there are eligible characters in word or 7, whichever is less. If number ends up containing more than 3 digits then a hyphen ( - ) should be placed between the third and fourth digits.
int len = (word.length()>7) ? 7 : word.length(); // A
if (i==3 && len > 3) { number += "-"; } // B
private void setNumber(){
// Insert A here
for (int i = 0; i <= len - 1; i++ )
// Insert B here
switch(word.charAt(i))
{