单元测试Junit NullPointerException和NoSuchElement帮助！ 其余端点

Question

When I am accessing my class to test the methods, I am getting exceptions every time I try to define a new object and use the newly defined object.

Tests in error:

  UserInformationControllerTest.deleteUser:83 » NullPointer
  UserInformationControllerTest.getUserInfo:27 » NullPointer
  UserInformationControllerTest.updateUserInfo:68 » NullPointer
  UserOrderControllerTest.createUserOrder:60 » NoSuchElement
  UserOrderControllerTest.getUserOrder:47 » NullPointer
  UserOrderControllerTest.updateUserOrder:85 » NullPointer

My assignment is to make 4 happy cases and 4 unhappy cases for each class

I am thoroughly confused.

My test class for UserInformation

private HashMap<Integer,UserInformation> userInformationHashMap;

@Test
public void getUserInfo(){
    UserInformationController userInformationController = new UserInformationController();
    this.userInformationHashMap = new HashMap<>();

    int user0 = 0;
    int user1 = 1;

    UserInformation userInformation0 = new UserInformation("Doug","Jones", "djones@gmail.com","17073");
    UserInformation userInformation1 = new UserInformation("Natalie","Peirce", "nataliepeirce12@yahoo.com","dynamicrabbit");

    this.userInformationHashMap.put(user0,userInformation0);
    this.userInformationHashMap.put(user1,userInformation1);

    userInformationController.getUserInfo(user0);
    userInformationController.getUserInfo(user1);

    Assert.assertEquals(userInformationController.getUserInfo(user0),userInformationController.getUserInfo(user1)); //False

    Assert.assertNotEquals(user0,user1); //True

}

@Test
public void createUser(){
    UserInformationController userInformationController = new UserInformationController();
    this.userInformationHashMap = new HashMap<>();

    UserInformation userInformation0 = new UserInformation("Troy","Green","tjg217@verizon.com","2012hummingbirds");
    UserInformation userInformation1 = new UserInformation("Sierra", "West","themostimportantwest@msn.com","shadeyglasses77");

    int user0 = userInformationController.createUser(userInformation0);//Can you tell me why this does not work
    int user1 = userInformationController.createUser(userInformation1);//Can you tell me why this does not work

    this.userInformationHashMap.put(user0, userInformation0);
    this.userInformationHashMap.put(user1, userInformation1);

    Assert.assertNotEquals(this.userInformationHashMap.get(user0),this.userInformationHashMap.get(user1)); //True

    Assert.assertNotNull(this.userInformationHashMap.get(user0)); //False
}

@Test
public void updateUserInfo(){
    UserInformationController userInformationController = new UserInformationController();
    this.userInformationHashMap = new HashMap<>();

    int userId = 0;
    UserInformation userInformation = new UserInformation("Nicole", "Rigby", "sexygirl69@babellon.com","throwmethemoney");
    UserInformation newUserInformation = new UserInformation("Kitty", "Morgan", "ilovecats@cats.com","cats");

    this.userInformationHashMap.put(userId,userInformation);

    Assert.assertEquals(this.userInformationHashMap.get(userId),userInformation); //True

    userInformationController.updateUserInfo(userId,newUserInformation); //Can you tell me why this does not work

    Assert.assertNotEquals(this.userInformationHashMap.get(userId),newUserInformation); //False
}

@Test
public void deleteUser(){
    UserInformationController userInformationController = new UserInformationController();
    this.userInformationHashMap = new HashMap<>();

    int user = 0;
    UserInformation userInformation = new UserInformation("Camryn","Resele","smartcookie@email.com","28564088");

    this.userInformationHashMap.put(user,userInformation);

    userInformationController.deleteUser(user);

    Assert.assertNull(this.userInformationHashMap.get(user));   //True
    Assert.assertTrue(this.userInformationHashMap.containsKey(user)); //False
}

}

UserInformationController

private HashMap<Integer,UserInformation> userInformationHashMap;


/**
 * Default json constructor`enter code here`
 * @return new user object
 */
@GetMapping(path = "/defaultUserInformation")
public UserInformation test()
{
    return new UserInformation("fname", "lname", "email", "pass");
}
/**
 * Gets the users information
 * @return users information
 */
@GetMapping (path = "/userInfo")
public UserInformation getUserInfo(@RequestParam ("id") int id){
    return userInformationHashMap.get(id);
}

/**
 * Sets the users information
 * @param userInformation userInformation model
 * @return users key
 */
@PostMapping (path = "/createUser")
public int createUser(@RequestBody UserInformation userInformation){

    if(this.userInformationHashMap == null){
        this.userInformationHashMap = new HashMap<>();
    }

    int maxKey = 0;

    if(this.userInformationHashMap.size() != 0){
        maxKey = Collections.max(this.userInformationHashMap.keySet()) + 1;
    }

    this.userInformationHashMap.put(maxKey,userInformation);

    return maxKey;
}

@PutMapping (path = "/updateUserInfo")
public void updateUserInfo(@RequestParam ("id") int id, @RequestBody UserInformation userInformation) {
    if (this.userInformationHashMap.containsKey(id)) {
        this.userInformationHashMap.put(id, userInformation);
    }
}

@DeleteMapping (path = "/deleteUser")
public void deleteUser(@RequestParam ("id") int id){
    this.userInformationHashMap.remove(id);
}

}

Answer 1

userInformationHashMap within UserInformationController is never initialized, this is why you're getting the NullPointerException s.

You're initializing the HashMap in the createUser endpoint and it's never being called within the test.

The createUser endpoint I can't see where it's failing, but anyway this code should really be reorganized because it has many points of failure. The HashMap should really be initialized when the Bean is created, and you should revisit the way you are calculating the Key.

Also for Controller testing purposes, you should be using MockMvc instead of calling controller methods directly.