iterators

HashMap<String, ArrayList<String>> map = ...;
for (Entry<String, ArrayList<String>> entry : map.entrySet()) {
    entry.getKey();
    entry.getValue();
}

String

public String[] split(String regex)

The string “boo:and:foo”, for example, yields the following results with these expressions:

Regex Result
: { "boo", "and", "foo" }
o { "b", "", ":and:f" }

Base conversion

int n = 1337;
String number = Integer.toString(n, 36);
int andBack = Integer.parseInt(number, 36);