Check length, negative, equilateral, isosceles

src/praktikum02/TriangleChecker.java

@@ -5,9 +5,7 @@ import java.util.Scanner;
 public class TriangleChecker {
 
     public enum TriangleType {
-        NONE,
-        NORMAL,
-        ISOSCELES,  // Gleichschenklig
+        NONE, NORMAL, ISOSCELES,  // Gleichschenklig
         EQUILATERAL // Gleichseitig
     }
 
@@ -49,13 +47,22 @@ public class TriangleChecker {
 
     // Analyse der Dreiecksart
     public static TriangleType checkTriangle(float a, float b, float c) {
-        if(a==b && a==c){
-            return TriangleType.EQUILATERAL;
+        if (a <= 0 || b <= 0 || c <= 0) {
+            return TriangleType.NONE;
         }
-        else{
-            return TriangleType.NORMAL;
+
+        if (a + b <= c || a + c <= b || b + c <= a) {
+            return TriangleType.NONE;
+        }
+
+        if (a == b && b == c) {
+            return TriangleType.EQUILATERAL;
         }
-    }
 
+        if (a == b || b == c || a == c) {
+            return TriangleType.ISOSCELES;
+        }
 
+        return TriangleType.NORMAL;
+    }
 }

test/praktikum02/TriangleCheckerTest.java

@@ -10,9 +10,23 @@ class TriangleCheckerTest {
     void checkTriangle() {
         assertEquals(TriangleChecker.TriangleType.NORMAL, TriangleChecker.checkTriangle(5, 6, 7));
     }
+
     @Test
     void checkGleichseitig() {
-       assertEquals(TriangleChecker.TriangleType.EQUILATERAL, TriangleChecker.checkTriangle(1,1,1));
+        assertEquals(TriangleChecker.TriangleType.EQUILATERAL, TriangleChecker.checkTriangle(1, 1, 1));
+    }
+
+    @Test
+    void checkNegativ() {
+        assertEquals(TriangleChecker.TriangleType.NONE, TriangleChecker.checkTriangle(-1, 3, 5));
+        assertEquals(TriangleChecker.TriangleType.NONE, TriangleChecker.checkTriangle(3, 0, 5));
+        assertEquals(TriangleChecker.TriangleType.NONE, TriangleChecker.checkTriangle(3, 5, -10));
+    }
+    @Test
+    void checkLength() {
+        assertEquals(TriangleChecker.TriangleType.NONE, TriangleChecker.checkTriangle(20, 3, 5));
+        assertEquals(TriangleChecker.TriangleType.NONE, TriangleChecker.checkTriangle(10, 20, 10));
+        assertEquals(TriangleChecker.TriangleType.NONE, TriangleChecker.checkTriangle(1, 1, 60));
     }
 
 }