Java: how to convert HashMap to array

Question

I need to convert a HashMap to an array; could anyone show me how it\'s done?

Answer 1

If you are using Java 8+ and need a 2 dimensional Array, perhaps for TestNG data providers, you can try:

map.entrySet()
    .stream()
    .map(e -> new Object[]{e.getKey(), e.getValue()})
    .toArray(Object[][]::new);

If your Objects are Strings and you need a String[][], try:

map.entrySet()
    .stream()
    .map(e -> new String[]{e.getKey(), e.getValue().toString()})
    .toArray(String[][]::new);