More refactoring and maintenance

1 files changed, 90 insertions, 0 deletions

diff --git a/dice-lang/src/main/java/bjc/dicelang/OperatorDiceExpression.java b/dice-lang/src/main/java/bjc/dicelang/OperatorDiceExpression.java
new file mode 100644
index 0000000..4ca2568
--- /dev/null
+++ b/dice-lang/src/main/java/bjc/dicelang/OperatorDiceExpression.java
@@ -0,0 +1,90 @@
+package bjc.dicelang;
+
+/**
+ * Implements a class for combining two dice with an operator
+ * 
+ * @author ben
+ *
+ */
+public class OperatorDiceExpression implements IDiceExpression {
+	/**
+	 * The operator to use for combining the dice
+	 */
+	private DiceExpressionType	det;
+
+	/**
+	 * The dice on the left side of the expression
+	 */
+	private IDiceExpression		left;
+
+	/**
+	 * The dice on the right side of the expression
+	 */
+	private IDiceExpression		right;
+
+	/**
+	 * Create a new compound expression using the specified parameters
+	 * 
+	 * @param right
+	 *            The die on the right side of the expression
+	 * @param left
+	 *            The die on the left side of the expression
+	 * @param det
+	 *            The operator to use for combining the dices
+	 */
+	public OperatorDiceExpression(IDiceExpression right,
+			IDiceExpression left, DiceExpressionType det) {
+		this.right = right;
+		this.left = left;
+		this.det = det;
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see bjc.utils.dice.IDiceExpression#roll()
+	 */
+	@Override
+	public int roll() {
+		/*
+		 * Handle each operator
+		 */
+		switch (det) {
+			case ADD:
+				return right.roll() + left.roll();
+			case SUBTRACT:
+				return right.roll() - left.roll();
+			case MULTIPLY:
+				return right.roll() * left.roll();
+			case DIVIDE:
+				/*
+				 * Round to keep results as integers. We don't really have
+				 * any need for floating-point dice
+				 */
+				try {
+					return right.roll() / left.roll();
+				} catch (ArithmeticException aex) {
+					throw new UnsupportedOperationException(
+							"Attempted to divide by zero."
+									+ " Problematic expression is "
+									+ left);
+				}
+			default:
+				throw new IllegalArgumentException(
+						"Got passed  a invalid ScalarExpressionType " + det
+								+ ". WAT");
+
+		}
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see java.lang.Object#toString()
+	 */
+	@Override
+	public String toString() {
+		return "dice-exp[type=" + det + ", l=" + left.toString() + ", r="
+				+ right.toString() + "]";
+	}
+}