TreeMap that contains String as key and a boolean as value?
<p>Hello I tried to create a TreeMap in Java but the compiler gives the error saying "unexpected type".
Can anyone tell me why? Isn't possible to have primitive data types in a Map?</p>

<p>I did solve it by using the java.lang.Boolean instead. But I don't understand why I can't mix a complex data type with a primitive one.</p>
