Java Plz fast I really need the answer

Relevant topics: array lists, stacks, queues, insertion sort.

Write a program that reads a string of up to 9 lower-case letters from the standard input and prints out the longest words (in words.txt) that can be formed by reordering the letters. Each input letter can be used at most once to form the out-put word. If there is more than one word of the maximum length, print out all of them in alphabetical order, each on a new line. Name your program LongestWords.

For example, if the input is

njwhoaurgthen

the correct output is

jargon

ourang

For full credit, your program should take no more than 30 seconds, and in no case should it take longer than 5 minutes.