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Welcome to the MDAAJ wiki!

What is MDDAJ?

Multidimensional Dynamic Array Api for Java. You can create dynamic multidimensional generic arrays at runtime.

How it works?

The There exist three implementations (extends from MDDABasic)

• MDDAReal The array ist not real multidimensional, its nested (nested dimension times)
• MDDACodeGen For this type, there will be generated a .class (byte code) at runtime with the specific dimension
• MDDAPseudo This class provides an multidimensional access for the user, but the array is internally only one dimensional

The MDDABasic function overview

// set the generic element at the indices (return type indicated if the it was successfull)
boolean set(T value, int... indices)
// get the generic element at the indices
public T get(int... indices) 
// fill the whole array with the generic value
public boolean fill(T value) 
// convert the array into one dimensional array
public T[] flatten()
// print the array
public void print()

Getting Started

The standard way to create an array looks like this:

int[] a = new int[10];
double[][] b = new double[10][20];
String[][][][][] c = new String[10][20][5][8][15];
c[0][0][2][1][0] = "xyz";
String s = c[0][0][0][0][0];

Creating the same array with MDDAJ:

MDDAPseudo<Integer> a = new MDDAPseudo<Integer>(10);
MDDAPseudo<Double> b = new MDDAPseudo<Double>(10,20);
MDDAPseudo<String> c = new MDDAPseudo<String>(10,20,5,8,15);
c.set("xyz", 0,0,2,1,0);
String s = c.get(0,0,0,0,0);

NeighborInterface

The MDDAPSeudo implements this interface and provides the neighbors elements of an element for a grid topology. For example in a 2d space your array have the dimension 3x3, MDDAPseudo<Integer> a = new MDDAPseudo<Integer>(3,3); The numbers are the internal one dimensional indicies:

0 - 1 - 2
|   |   |
3 - 4 - 5
|   |   |
6 - 7 - 8

int distance = 1;
Set<Integer> getNeighbors = a.getNeighborForAllDims(distance, 1,1) // indices (1,1) -> 4
// getNeighbors = {1,3,5,7}
Set<Integer> getNeighbors2 = a.getNeighborForAllDims(distance+1, 1,1) // indices (1,1) -> 4
// getNeighbors2 = {1,3,5,7,0,2,6,8}

You can also call a.getNeighborForDim(distance, 1, 1,1) for only the 2nd dimension, the result will be {3,5}