Converting Binomial Tree in C++ to Java

I have the following code that I am trying to convert from C++ into Java. The code is supposed to generate a binomial tree that will be used calculate stock option prices. Here is the following C++ code:

class Price {
public:
    double stockPrice;
    double optionPrice;
};

int numIntervals = 500;
Price ** binomialTree;
binomialTree = new Price*[numIntervals+1];

for (i = 0; i <= numIntervals; i++) {
    binomialTree[i] = new Price[i + 1];
}
for (i = 0; i <= numIntervals; i++) {
    for (j = 0; j <= i; j++) {
        binomialTree[i][j].stockPrice = sNaught * pow(up, j) * pow(down, i-j);
    }
}

I need the java code that will initialize the binomial tree so that I can iterate through it and calculate the various prices. The part that is throwing me off is the binomialTree[i] = new Price[i+1]; which occurs inside the loop, making the 2D array dynamic which you can't do in java. This is what I came up with which runs but the resulting price is incorrect with compared to the values given.

class Price {
    double stockPrice = 0.0;
    double optionPrice = 0.0;

    Price(double sP, double oP) {
        this.stockPrice = sP;
        this.optionPrice = oP;
    }
}

int i,j;
Price[][] binomialTree = new Price[numIntervals+1][numIntervals+2];

for (i = 0; i <= numIntervals; i++) {
    for (j = 0; j <= i; j++) {
        binomialTree[i][j] =  new Price(option.getsNought() * Math.pow(up, j) * Math.pow(down, i-j), 0);
    }
}

Two dimensional arrays whose row length is dynamic are very much possible in Java. Since I don't have your entire settings, here is a short example for you:

     Price[][] binomialTree = new Price[20][];
     for ( int i = 0 ; i < 20 ; i++ ) {
         binomialTree[i] = new Price[i+1];
     }

     for ( int i = 0; i < 20; i ++ ) {
          System.out.println( Arrays.toString(binomialTree[i]));
     }

The output of this is (since we haven't populated the arrays):

[null]
[null, null]
[null, null, null]
[null, null, null, null]
...

It is worth noting that Java does not have "two dimensional arrays" (in the sense that all dimensions are allocated together as a consecutive chunk of memory) at all. All it has is one-dimensional arrays, whose base type can be a reference type. And the reference type can be that of an array.

A declaration such as

Price[][] arr = new Price[5][7];

is merely syntactic sugar that does the same as creating a 5-element array of references to arrays of Price, then creating 5 arrays of 7 references to Price and assigning them to each element of that first array.

For a formal discussion of this, read the Java Language Specification.