first commit

java/expression/exceptions/CheckedDivide.java

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+package expression.exceptions;
+
+import java.math.BigDecimal;
+import java.math.BigInteger;
+import java.math.MathContext;
+
+import expression.*;
+
+/**
+ * @author Doschennikov Nikita (me@fymio.us)
+ */
+public class CheckedDivide extends AbstractBinaryOperation {
+    public CheckedDivide(AbstractExpression l, AbstractExpression r) { super(l, r); }
+
+    @Override protected String  getOperator()  { return "/"; }
+    @Override protected int     getPriority()  { return 2; }
+    @Override protected boolean isRightAssoc() { return true; }
+
+    @Override
+    protected int applyInt(int a, int b) {
+        if (b == 0) throw new DivisionByZeroException();
+        if (a == Integer.MIN_VALUE && b == -1) throw new OverflowException("division");
+        return a / b;
+    }
+
+    @Override
+    protected BigInteger applyBi(BigInteger a, BigInteger b) {
+        if (b.signum() == 0) throw new DivisionByZeroException();
+        return a.divide(b);
+    }
+
+    @Override
+    protected BigDecimal applyBd(BigDecimal a, BigDecimal b) {
+        if (b.signum() == 0) throw new DivisionByZeroException();
+        return a.divide(b, MathContext.DECIMAL128);
+    }
+}