Iterate over map using entrySet()
Given a Map
composed of String
keys and Integer
values, the following iterates over its entries using the entrySet()
feature.
Map<String, Integer> map = new HashMap<>();
for (Map.Entry<String, Integer> entry : map.entrySet()) {
String key = entry.getKey();
String value = entry.getValue();
// ...
}
Iterate over map using keySet()
Given a Map
composed of String
keys and Integer
values, the following iterates over its entries using the keySet()
feature.
Map<String, Integer> map = new HashMap<>();
for (String key : map.keySet()) {
String value = map.get(key);
// ...
}
Explanation
Java Maps
are a powerful data structure capable of holding key/pair values, allowing developers to have something similar to a dictionary, where words are the key and the definition are the values. Iterating over these data structures is not as straightforward as it is for arrays
or Lists
, but the above code bits outline how this can be achieved. See more about the conversion of Map to List here.