first commit

java/expression/AbstractExpression.java

@@ -0,0 +1,42 @@
+package expression;
+
+import java.math.BigDecimal;
+import java.math.BigInteger;
+import java.util.List;
+
+/**
+ * @author Doschennikov Nikita (me@fymio.us)
+ */
+public abstract class AbstractExpression
+    implements
+        Expression,
+        TripleExpression,
+        ListExpression,
+        BigIntegerListExpression,
+        BigDecimalListExpression
+{
+
+    @Override
+    public abstract int evaluate(int x);
+
+    @Override
+    public abstract int evaluate(int x, int y, int z);
+
+    @Override
+    public abstract int evaluate(List<Integer> vars);
+
+    @Override
+    public abstract BigInteger evaluateBi(List<BigInteger> vars);
+
+    @Override
+    public abstract BigDecimal evaluateBd(List<BigDecimal> vars);
+
+    @Override
+    public abstract String toString();
+
+    @Override
+    public abstract boolean equals(Object obj);
+
+    @Override
+    public abstract int hashCode();
+}