Java code to find all the anagrams of a given string

Two strings are called anagrams if they contain same set of characters but in different order. For example, “keep” and “peek“.

import java.util.Collection;
import java.util.HashSet;
import java.util.Set;


public class AllAnagrams {

	private static Set anagrams;

	public static Collection getAllAnagrams(String string) {
		anagrams = new HashSet();
		permutation("", string);
		return anagrams;
	}

	public static void main(String[] args) {
		Collection anagrams = getAllAnagrams("peek");
		for (String a : anagrams)
			System.out.println(a);
	}

	private static void permutation(String prefix, String suffix) {
		int suffixLength = suffix.length();
		if (suffixLength == 0) {
			anagrams.add(prefix);
		} else {
			for (int i = 0; i < suffixLength; i++) {
				permutation(prefix + suffix.charAt(i), suffix.substring(0, i) + suffix.substring(i + 1, suffixLength));
			}
		}
	}
}

Would give the following result:

eepk
ekpe
kpee
keep
epke
eekp
peke
kepe
epek
ekep
peek
pkee

Java Code to determine if two strings are anagrams of each other:

import java.util.ArrayList;
import java.util.List;

public class AreAnagrams {

	public static boolean areAnagrams(String a, String b) {
		List word = new ArrayList();
		for (int i = 0; i < b.toCharArray().length; i++) {
			word.add(b.charAt(i));
		}
		boolean ok = true;
		int i = 0;
		while (ok && i < a.toCharArray().length) {
			Character c = a.charAt(i);
			if (!word.contains(c)) {
				ok = false;
			}
			word.remove(c);
			i++;
		}
		return ok;
	}

	public static void main(String[] args) {
		System.out.println(areAnagrams("apple", "pleap"));
		System.out.println(areAnagrams("neural", "unreal"));
		System.out.println(areAnagrams("neurls", "unreal"));
		System.out.println(areAnagrams("orchestra", "carthorse"));
		System.out.println(areAnagrams("orange", "apple"));
		System.out.println(areAnagrams("ape", "monkey"));
	}
}