How does java.util.Map's getOrDefault() work?

Question

I noticed that if I do map.getOrDefault(\"key1\", new Object()), even if object is present for key1 in the map, new Object() is created. Though it is n

Answer 1

look in the java 8 implementation:

default V getOrDefault(Object key, V defaultValue) {
    V v;
    return (((v = get(key)) != null) || containsKey(key))
        ? v
        : defaultValue;
}

the doc specifies:

Returns the value to which the specified key is mapped, or defaultValue if this map contains no mapping for the key. ault

it will return the default is not present in the map

example:

    Map map = new HashMap<>();

    map.put("1", "Foo");
    //search for the entry with key==1, since present, returns foo
    System.out.println(map.getOrDefault("1", "dumnba"));
    //search for the entry with key==2, since not present, returns dumnba
    System.out.println(map.getOrDefault("2", "dumnba"));