Java tutorial
//package com.java2s; /* *********************************************************************** * * project: org.matsim.* * CollectionUtils.java * * * *********************************************************************** * * * * copyright : (C) 2011 by the members listed in the COPYING, * * LICENSE and WARRANTY file. * * email : info at matsim dot org * * * * *********************************************************************** * * * * This program is free software; you can redistribute it and/or modify * * it under the terms of the GNU General Public License as published by * * the Free Software Foundation; either version 2 of the License, or * * (at your option) any later version. * * See also COPYING, LICENSE and WARRANTY file * * * * *********************************************************************** */ import java.util.ArrayList; import java.util.Collection; import java.util.Iterator; import java.util.List; public class Main { public static <T> List<T>[] split(Collection<T> set, int n) { if (set.size() >= n) { @SuppressWarnings("unchecked") List<T>[] arrays = new List[n]; int minSegmentSize = (int) Math.floor(set.size() / (double) n); int start = 0; int stop = minSegmentSize; Iterator<T> it = set.iterator(); for (int i = 0; i < n - 1; i++) { int segmentSize = stop - start; List<T> segment = new ArrayList<T>(segmentSize); for (int k = 0; k < segmentSize; k++) { segment.add(it.next()); } arrays[i] = segment; start = stop; stop += segmentSize; } int segmentSize = set.size() - start; List<T> segment = new ArrayList<T>(segmentSize); for (int k = 0; k < segmentSize; k++) { segment.add(it.next()); } arrays[n - 1] = segment; return arrays; } else { throw new IllegalArgumentException("n must not be smaller set size!"); } } }