public class TheClass {
private Map<String, String> theMap;
public TheClass() {
theMap = new HashMap<>();
}
}
How to create a map instance variable
-
12-06-2023 - |
Domanda
I've been trying to create a class that will model a scenario I've come up with. It will involve a map with string keys and values.
I need to create an instance variable used to reference the map object, and a constructor that creates the empty map and assigns it to the map instance variable.
I've been messing around with map objects but not creating a class using them, and I've hit a mental block!
What's the proper way to actually get a map object?
Soluzione
Altri suggerimenti
public class Demo {
Map<String,String> map = null;
public Demo()
{
map = new HashMap<String,String>();
}
}
If you want to use HashMap which is Map implementation you can do it like that:
Map<String, String> map = new HashMap<String, String>();
or
Map<String, String> map = new HashMap<>();
in Java 7.
You can also use other implementations like TreeMap.
You can use the HashMap which is an implementation of Map http://docs.oracle.com/javase/7/docs/api/java/util/HashMap.html
Map<String,String> map = new HashMap<String,String>();
map.put("key1", "Value1");
map.put("Key2", "Value2");