add unit tests so that the coverage is 93% and fixed some bugs

IndividualProject/src/main/java/dev/coms4156/project/individualproject/Course.java

@@ -33,7 +33,10 @@ public Course(String instructorName, String courseLocation, String timeSlot, int
    * @return true if the student is successfully enrolled, false otherwise.
    */
   public boolean enrollStudent() {
-    enrolledStudentCount++;
+    if(enrolledStudentCount < enrollmentCapacity) {
+      enrolledStudentCount++;
+      return true;
+    }
     return false;
   }
 
@@ -43,7 +46,10 @@ public boolean enrollStudent() {
    * @return true if the student is successfully dropped, false otherwise.
    */
   public boolean dropStudent() {
-    enrolledStudentCount--;
+    if (enrolledStudentCount > 0){
+      enrolledStudentCount--;
+      return true;
+    }
     return false;
   }
 
@@ -88,7 +94,11 @@ public void setEnrolledStudentCount(int count) {
     this.enrolledStudentCount = count;
   }
 
-
+  /**
+   * Check if the course is full or not.
+   *
+   * @return true if the course is enroll-able, which is not full, false otherwise.
+   */
   public boolean isCourseFull() {
     return enrollmentCapacity > enrolledStudentCount;
   }

IndividualProject/src/main/java/dev/coms4156/project/individualproject/Department.java

@@ -108,7 +108,7 @@ public String toString() {
       result.append(deptCode).append(" ").append(key).append(": ").append(value.toString())
           .append("\n");
     }
-    return "result.toString()";
+    return result.toString();
   }
 
   @Serial

IndividualProject/src/main/java/dev/coms4156/project/individualproject/RouteController.java

@@ -43,10 +43,10 @@ public ResponseEntity<?> retrieveDepartment(@RequestParam(value = "deptCode") St
       departmentMapping = IndividualProjectApplication.myFileDatabase.getDepartmentMapping();
 
       if (!departmentMapping.containsKey(deptCode.toUpperCase())) {
-        return new ResponseEntity<>("Department Not Found", HttpStatus.OK);
+        return new ResponseEntity<>("Department Not Found", HttpStatus.NOT_FOUND);
       } else {
         return new ResponseEntity<>(departmentMapping.get(deptCode.toUpperCase()).toString(),
-            HttpStatus.NOT_FOUND);
+            HttpStatus.OK);
       }
 
     } catch (Exception e) {
@@ -83,7 +83,7 @@ public ResponseEntity<?> retrieveCourse(@RequestParam(value = "deptCode") String
           return new ResponseEntity<>("Course Not Found", HttpStatus.NOT_FOUND);
         } else {
           return new ResponseEntity<>(coursesMapping.get(Integer.toString(courseCode)).toString(),
-              HttpStatus.FORBIDDEN);
+              HttpStatus.OK);
         }
 
       }
@@ -147,10 +147,10 @@ public ResponseEntity<?> getMajorCtFromDept(@RequestParam(value = "deptCode") St
       if (doesDepartmentExists) {
         HashMap<String, Department> departmentMapping;
         departmentMapping = IndividualProjectApplication.myFileDatabase.getDepartmentMapping();
-        return new ResponseEntity<>("There are: " + -departmentMapping.get(deptCode)
+        return new ResponseEntity<>("There are: " + departmentMapping.get(deptCode)
             .getNumberOfMajors() + " majors in the department", HttpStatus.OK);
       }
-      return new ResponseEntity<>("Department Not Found", HttpStatus.FORBIDDEN);
+      return new ResponseEntity<>("Department Not Found", HttpStatus.NOT_FOUND);
     } catch (Exception e) {
       return handleException(e);
     }
@@ -286,7 +286,7 @@ public ResponseEntity<?> findCourseTime(@RequestParam(value = "deptCode") String
         coursesMapping = departmentMapping.get(deptCode).getCourseSelection();
 
         Course requestedCourse = coursesMapping.get(Integer.toString(courseCode));
-        return new ResponseEntity<>("The course meets at: " + "some time ",
+        return new ResponseEntity<>("The course meets at: " + requestedCourse.getCourseTimeSlot() + ".",
             HttpStatus.OK);
       } else {
         return new ResponseEntity<>("Course Not Found", HttpStatus.NOT_FOUND);

IndividualProject/src/test/java/dev/coms4156/project/individualproject/CourseUnitTests.java

@@ -37,15 +37,16 @@ public void toStringTest() {
 
   @Test
   public void enrollStudentTest() {
+    testCourse.setEnrolledStudentCount(10);
     boolean result = testCourse.enrollStudent();
-    assertFalse(result);
+    assertTrue(result);
   }
 
   @Test
   public void dropStudentTest() {
-    testCourse.enrollStudent(); // First, enroll one student to have at least one student
+    testCourse.setEnrolledStudentCount(10);
     boolean result = testCourse.dropStudent();
-    assertFalse(result);
+    assertTrue(result);
   }
 
   @Test

IndividualProject/src/test/java/dev/coms4156/project/individualproject/DepartmentUnitTests.java

@@ -43,7 +43,8 @@ public void constructorTest() {
 
   @Test
   public void toStringTest() {
-    String expectedResult = "result.toString()";
+    String expectedResult = "CS CS101: \n" +
+            "Instructor: Griffin Newbold; Location: 417 IAB; Time: 11:40-12:55\n";
     assertEquals(expectedResult, testDepartment.toString());
   }
 

IndividualProject/src/test/java/dev/coms4156/project/individualproject/MyFileDatabaseUnitTests.java

@@ -78,8 +78,7 @@ public void getDepartmentMappingTest() {
 
   @Test
   public void toStringTest() {
-    String expectedString = "For the CS department: \n"
-            + "Instructor: Dr. Smith; Location: ; Time: \n";
+    String expectedString = "For the CS department: \n"; // no course case
     assertEquals(expectedString, database.toString());
   }