I have a HashMap
with various keys and values, how can I get one value out?
I have a key in the map called my_code
, it should contain a string, how can I just get that without having to iterate through the map?
So far I've got..
HashMap newMap = new HashMap(paramMap);
String s = newMap.get("my_code").toString();
I'm expecting to see a String
, such as "ABC" or "DEF" as that is what I put in there initially, but if I do a System.out.println()
I get something like java.lang.string#F0454
Sorry, I'm not too familiar with maps as you can probably guess ;)
Just use Map#get(key)
?
Object value = map.get(myCode);
Here's a tutorial about maps, you may find it useful: http://java.sun.com/docs/books/tutorial/collections/interfaces/map.html.
Edit: you edited your question with the following:
I'm expecting to see a String, such as "ABC" or "DEF" as that is what I put in there initially, but if I do a System.out.println() I get something like java.lang.string#F0454
Sorry, I'm not too familiar with maps as you can probably guess ;)
You're seeing the outcome of Object#toString()
. But the java.lang.String
should already have one implemented, unless you created a custom implementation with a lowercase s
in the name: java.lang.string
. If it is actually a custom object, then you need to override Object#toString()
to get a "human readable string" whenever you do a System.out.println()
or toString()
on the desired object. For example:
@Override
public String toString() {
return "This is Object X with a property value " + value;
}