Java: how to convert a List<?> to a Map<String,?> [duplicate]

Answer 1

Using Guava (formerly Google Collections):

Map mappedRoles = Maps.uniqueIndex(yourList, Functions.toStringFunction());

Or, if you want to supply your own method that makes a String out of the object:

Map mappedRoles = Maps.uniqueIndex(yourList, new Function() {
  public String apply(Role from) {
    return from.getName(); // or something else
  }});