a = 0, b = 0, c = 0, x - любое (бесконечное число решений)

levelp · May 23, 2015 · bb06ad4 · bb06ad4
1 parent 4dae578
commit bb06ad4
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Showing 3 changed files with 17 additions and 1 deletion.
diff --git a/src/main/java/AnyXException.java b/src/main/java/AnyXException.java
@@ -0,0 +1,5 @@
+/**
+ * Исключение - x может быть любым
+ */
+public class AnyXException extends RuntimeException {
+}
diff --git a/src/main/java/QuadraticEquation.java b/src/main/java/QuadraticEquation.java
@@ -14,8 +14,11 @@ public class QuadraticEquation {
      */
     public static double[] solve(double a, double b, double c) {
         if (Math.abs(a) < EPS) {
-            if (Math.abs(b) < EPS)
+            if (Math.abs(b) < EPS) {
+                if (Math.abs(c) < EPS)
+                    throw new AnyXException();
                 return new double[]{};
+            }
             return new double[]{-c / b};
         }
         // Дискриминант

diff --git a/src/test/java/QuadraticEquationTest.java b/src/test/java/QuadraticEquationTest.java
@@ -62,4 +62,12 @@ public void testABZeroNoRoots() {
         assertArrayEquals("4.5 = 0", new double[]{}, QuadraticEquation.solve(0, 0, 4.5), EPS);
     }
 
+    /**
+     * a = 0, b = 0, c = 0, x - любое (бесконечное число решений)
+     * Это не возможно выразить с помощью массива double => генерируем исключение
+     */
+    @Test(expected = AnyXException.class)
+    public void testABСZero() {
+        QuadraticEquation.solve(0, 0, 0);
+    }
 }