Compiling Error, need help!!

Question

Having trouble compiling the following code...
Anyone have any ideas!?
Error on line 14:
public Q(String s) {
The blank final field num may not have been initialized     
The blank final field denom may not have been initialized     
public class Q extends AbstractNumber implements Number {
     private final Z num;
     private final Z denom;
        public static final Q UNDEFINED = new Q();
     public static final Q ZERO = new Q(Z.ZERO, Z.ONE);
     public static final Q ONE = new Q(Z.ONE, Z.ONE);
     public Q ()     {
          this.num = Z.UNDEFINED;
          this.denom = Z.UNDEFINED;
     public Q(String s) {
          String rational[] = s.split("/");
          Z numz, denomz;
          if(rational.length == 1){
               numz = new Z(rational[0]);
               denomz = Z.ONE;
          else {
               if(rational.length == 2){
                    numz = new Z(rational[0]);
                    denomz = new Z(rational[1]);
               else {
                    throw new RuntimeException("Cannot make a Q from " + s);     
               this.num = numz;
               this.denom = denomz;
          public Q(Z numz, Z denomz) {
          if(denomz.equals(Z.ZERO)) {
               this.num = Z.UNDEFINED;
               this.denom = Z.UNDEFINED;
          else {
               if(numz.equals(Z.ZERO)) {
                    this.num = Z.ZERO;
                    this.denom = Z.ONE;
               else {
                    Z gcd = numz.gcd(denomz);
                    numz = numz.dividedBy(gcd);
                    denomz = denomz.dividedBy(gcd);
                    if(!(denomz.sign() == numz.sign())) {
                         numz = new Z(-1, numz.magnitude());
                         denomz = new Z(1, denomz.magnitude());
                    this.num = numz;
                    this.denom = denomz;
          public String toString() {
               if(this.isUndefined()) { return "Undefined";
               else {
                    if(this.getDenomz().equals(Z.ONE)) {
                         return this.getNumz().toString();
                    else {
                         return this.num + "/" + this.denom;          
     public Z getNumz()     { return this.num;     }
     public Z getDenomz() { return this.denom; }
     // Implementation of Number Interface     
     public Q undef () { return UNDEFINED; }
    public Q additiveIdentity () { return ZERO; }
    public Q multiplicativeIdentity () { return ONE; }
    public Q plus(Number n) {
     if (!this.getClass().equals(n.getClass()) || this.isUndefined() || n.isUndefined()) return undef();
     Q that = (Q) n;
     return new Q((this.num.times(that.getDenomz())).plus(that.getNumz().times(this.denom)), this.denom.times(that.getDenomz()));
        public Q times(Number n) {
     if (!this.getClass().equals(n.getClass()) || this.isUndefined() || n.isUndefined()) return undef();          
     Q that = (Q) n;          
     return new Q(this.getNumz().times(that.getNumz()), this.getDenomz().times(that.getDenomz()));
     public Q minus(Number n) {
          if (!(this.getClass()).equals(n.getClass()) || this.isUndefined() || n.isUndefined()) return undef();
          Q that = (Q) n;
          return this.plus(that.additiveInverse());
     public Q dividedBy(Number n) {
          if (!(this.getClass()).equals(n.getClass()) || this.isUndefined() || n.isUndefined()) return undef();
          Q that = (Q) n;
          return this.times(that.multiplicativeInverse());
     public Q toThe(Number n) {
          if (!(this.getClass()).equals(n.getClass()) || this.isUndefined() || n.isUndefined()) return undef();
          Q that = (Q) n;
          if(that.getDenomz().equals(Z.ONE)) { return new Q(this.getNumz().toThe(that.getNumz()), this.getDenomz().toThe(that.getNumz()));
          else { return undef();
     public Q additiveInverse() {
             return new Q(this.getNumz().additiveInverse(),this.getDenomz());
         public Q multiplicativeInverse() {
                  return new Q(this.getDenomz(),this.getNumz());
     // Implementation of Comparable Interface
     public int compareTo (Object o) {
            if (!this.getClass().equals(o.getClass()))
            throw new ClassCastException("Cannot compare " + this + " to " + o);
             Q that = (Q) o;
               if(this.getDenomz().equals(that.getDenomz())) {     return this.getNumz().compareTo(that.getNumz());
          else {
               if(!(this.getNumz().equals(Z.UNDEFINED) || this.getDenomz().equals(Z.UNDEFINED) || that.getNumz().equals(Z.UNDEFINED) || that.getDenomz().equals(Z.UNDEFINED))) {
                    return (this.getNumz().times(that.getDenomz())).compareTo(that.getNumz().times(this.getDenomz()));
               else {
                    return -1;
}

Answer 1

Ok, I've fixed the code by editing the lines:
public Q (String s) {
          String rational[] = s.split("/");
          Z numz, denomz;
          if(rational.length == 1){
               numz = new Z(rational[0]);
               denomz = Z.ONE;
          else {
               if(rational.length == 2){
                    numz = new Z(rational[0]);
                    denomz = new Z(rational[1]);
               else {
                    throw new RuntimeException("Cannot make a Q from " + s);     
          if(denomz.equals(Z.ZERO)) {
               this.num = Z.UNDEFINED;
               this.denom = Z.UNDEFINED;
          else {
               if(numz.equals(Z.ZERO)) {
                    this.num = Z.ZERO;
                    this.denom = Z.ONE;
               else
                    Z gcd = numz.gcd(denomz);
                    numz = numz.dividedBy(gcd);
                    denomz = denomz.dividedBy(gcd);
                    if(!(denomz.sign() == numz.sign()))
                         numz = new Z(-1, numz.magnitude());
                         denomz = new Z(1, denomz.magnitude());
                    this.num = numz;
                    this.denom = denomz;
}But I was wondering if there was any way to avoid the repetition. I'm basically just repeating what's in:
public Q(Z numz, Z denomz)