带有多个键和值的哈希图？

Question

I want to create a HashMap that looks like this:

{LOCATION =[China,Sydney, New York,...], NAME = [Bob Smith, Martha Stewart, Amanda Holmes,....], ORGANIZATION = [Matrix Inc, Paragon Pharmaceuticals, Wills Corp.,...]}

I have more than 1 key with multiple values. Whats the best way to do this?

Answer 1

What you need is a Map<String, List<String>>

example:

Map<String, List<String>> myMap = new HashMap<>();

myMap.put("Location", Arrays.asList("a", "b", "c"));
myMap.put("Name", Arrays.asList("b", "mar", "ama"));
myMap.put("Org", Arrays.asList("ma", "par", "wil"));

System.out.println(myMap);

output:

{Org=[ma, par, wil], Location=[a, b, c], Name=[b, mar, ama]}

Answer 2

You can create this structure:

Map<String, List<String>> map = new HashMap<>();

Although, it'd be more efficient if you know the structure to create an object with the inner lists.