Iterate through map values with IF

Question

For some reason I cannot get my iteration working. I have two classes, Cars and Garage. I have Map<Integer, Cars> cars = newHashMap<>(); within the Garage class and I want to iterate through all the Car objects in Map looking for a value of "Ford" and then print it out.

Any help/explanations would be great as very much a newbie.

private String model;
model = "Ford";

public void carMake() {
    for (Cars eachCar : cars.values()) {
        if (cars.containsValue(model)) {
            System.out.println("It is a ford");
        }
    }     
}

shouldn't you ask something like `if (eachCar.model().equals(model))`? — Turing85, Apr 18 '18 at 19:11
show the `Cars` class and expand upon your description otherwise, your question is ambiguous. — Ousmane D., Apr 18 '18 at 19:13
Assuming class Car { String model; } you should check either eachCar.getModel() equality to "Ford" — Akceptor, Apr 18 '18 at 19:14
Thank you Akceptor, you've helped answer my question. Apologies if my explanation/question/terminology was not as clear as it should be as it's all still very new to me. — Scotty, Apr 18 '18 at 19:22
it would be helpful if you posted both garage and cars classes — scigs, Apr 18 '18 at 19:22
Seems duplicate of stackoverflow question: https://stackoverflow.com/questions/5230545/find-if-hashmap-contains-chosen-value-and-return-key — Flying Dutchman, Apr 18 '18 at 19:26

Glim · Accepted Answer · 2018-04-18T19:20:15.740

Try it, supposing that class Car has a getModel() function that returns the car Model (Ford):

public void carMake() {
    for(Cars eachCar : cars.values()) {
        if("Ford".equals(eachCar.getModel()) {
             System.out.println("It is a ford");
        }
    }
}

In your code each interaction checks if your map (that contains Cars value) contains your model (that is a String). Even if you suppose that your model variable is a Car with model value = "Ford", each interaction you are checking the entire map, not the current value.

Iterate through map values with IF

1 Answers1