java get if contains else 0

To get a value from a list if it contains a specific element, and 0 if it does not, you can use the contains method of the List interface and the get method.

Here is an example using a list of integers:

List<Integer> list = Arrays.asList(1, 2, 3, 4, 5);
int value = list.contains(3) ? list.get(list.indexOf(3)) : 0;

The contains method returns true if the list contains the specified element, and false if it does not. The indexOf method returns the index of the first occurrence of the specified element in the list, or -1 if the element is not present.

In this case, the value variable will be assigned the value 3 if the list contains the element 3, and 0 if it does not.

You can also use the getOrDefault method of the Map interface to achieve a similar effect. For example:

Map<String, Integer> map = new HashMap<>();
map.put("a", 1);
map.put("b", 2);
map.put("c", 3);

int value = map.getOrDefault("b", 0);

This will assign the value 2 to the value variable if the map contains the key "b", and 0 if it does not.