Quick Java Tips - List conversions

Here are some quick Java tips. This is based on my recent code reviews.

1. How to convert HashMap keys to an ArrayList?
new ArrayList(map.keySet());

2. How to convert an Array to an ArrayList?
new java.util.ArrayList(java.util.Arrays.asList(array));

3. How to create and initialize a List in one step?
java.util.List = java.util.Arrays.asList(new String[] {”1″, “2″});

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