diff --git a/Java/explanation.txt b/Java/explanation.txt
new file mode 100644
index 0000000..624a6b9
--- /dev/null
+++ b/Java/explanation.txt
@@ -0,0 +1,16 @@
+I had to change the algorithm with java. Instead of the standard rook and bishop knight move generation, I split 
+them up into direction and then get each direction individually. This is slower but stops me need a 54x4096 and
+64x512 array. This is a problem because ulongs are directly supported in java.
+
+You have two choices
+1. convert all the constants to minus if they are over the max a signed long and risk a lot of bugs and testing that way.
+2. convert all the constants to BigIntegers like this:
+     static final BigInteger MAX_ULONG = new BigInteger("18446744073709551615");
+This means replacing all values with this type in all constants. You also need to use OOP for everything.
+This:
+    BigInteger bitboard = bitboard1 & bitboard2;
+Turns into:
+    BigInteger bitboard = bitboard1.and(bitboard2);
+
+I chose the second approach and tried converting everything over to this. I created so many bugs that I couldn't fix and 
+gave up in the end.