Added shoot() function to Coordinate class with first test case

src/main/java/de/tims/fleetstorm/matchfield/Coordinate.java

@@ -44,4 +44,8 @@ public class Coordinate {
 		System.out.println("X = " + this.x + ", Y = " + this.y + ", State = " + this.state);
 	}
 
+	public void shoot() {
+		this.setState(Coordinate.HIT);
+	}
+
 }

src/test/java/de/tims/fleetstorm/matchfield/CoordinateTest.java

@@ -44,4 +44,23 @@ class CoordinateTest {
 				Arguments.of("State = EMPTY", 0, Coordinate.EMPTY, Coordinate.EMPTY));
 	}
 
+	@ParameterizedTest(name = "test if shoot function sets correct field states")
+	@MethodSource("ShootFunctionFieldStates")
+	void testShootFunctionSetsCorrectFieldStates(String testName, Coordinate coordinateToTest, int expectedState) {
+		Matchfield matchfield = new Matchfield(10);
+		matchfield.createMatchfield();
+
+		// set dummy ship
+		matchfield.setShip(new Coordinate(0, 0), 5, 0);
+
+		Coordinate realCoordinate = matchfield.getField(coordinateToTest);
+		realCoordinate.shoot();
+		int calculatedResult = realCoordinate.getState();
+		assertThat(calculatedResult).describedAs(testName).isEqualTo(expectedState);
+	}
+
+	static Stream<Arguments> ShootFunctionFieldStates() {
+		return Stream.of(Arguments.of("Field State is HIT", new Coordinate(0, 0), Coordinate.HIT));
+	}
+
 }