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    <p>Looks like what you are looking for is for some way to declare how many dimensions an array has at runtime. I don't know how this could be done using a multidimensional ArrayList, or any multidimensional structure where you have to specify the dimensionality at compile time.</p> <p>The only answer I see is to use a simple linear array wrapped in a class that converts multidimensional coordinate to and from the its position in the underlying array. This is basically how languages such as C stores multidimensional arrays by using one contiguous chunk of memory.</p> <p>The code would look something like this:</p> <pre><code>import java.util.*; class MultiArray&lt;T&gt;{ private int[] dimensions; private Object[] array; public MultiArray(int ... dimensions){ this.dimensions=dimensions; //Utils.product returns the product of the ints in an array array=new Object[Utils.product(dimensions)]; } public void set(T value, int ... coords){ int pos=computePos(coords); array[pos]=value; } public T get(int ... coords){ int pos=computePos(coords); return (T)(array[pos]); } private int computePos(int[] coords){ int pos=0; int factor=1; for (int i=0;i&lt;coords.length;i++){ pos+=factor*coords[i]; factor*=dimensions[i]; } return pos; } } class Main{ public static void main(String args[]){ MultiArray&lt;Integer&gt; m=new MultiArray&lt;Integer&gt;(new int[]{5,4,3}); Random r=new Random(); for(int i=0;i&lt;5;i++) for(int j=0;j&lt;4;j++) for(int k=0;k&lt;3;k++) m.set(r.nextInt(),i,j,k); for(int i=0;i&lt;5;i++){ for(int j=0;j&lt;4;j++){ for(int k=0;k&lt;3;k++) System.out.print(m.get(i,j,k)+" "); System.out.println(""); } System.out.println("\n"); } } } class Utils{ public static int product(int...a){ int ret=1; for (int x:a) ret*=x; return ret; } } </code></pre>
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    1. CO@High-Performance Mark: Thanks :).
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    2. COHi just an update, I've just managed to sucessfully implement a version of this so thanks to you, and also to High-Performance Mark who had the same idea essentially. The benefits of this method for anyone interested include picking a random point in the lattice/array with just 1 random() statement, rather than N (number of dimensions). Also initialising or doing any bulk sequential stuff can be done with 1 for-loop rather than N loops. Thanks again, Hemmer
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