Java Set sub set split(Set original, int subsetSize)

Description

Split a set into subsets

License

Apache License

Parameter

Parameter	Description
original	The original set to be split
subsetSize	Size of the subset (except for final subset)
T	Data type of set elements

Return

List of subsets

Declaration

public static <T> List<Set<T>> split(Set<T> original, int subsetSize) 

Method Source Code

//package com.java2s;
/**/*w ww. java 2s .c o m*/
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import java.util.ArrayList;
import java.util.Iterator;
import java.util.LinkedHashSet;
import java.util.List;
import java.util.Set;
import java.util.Collections;

public class Main {
    /**
     * Split a set into subsets
     * @param original The original set to be split
     * @param subsetSize Size of the subset (except for final subset)
     * @param <T> Data type of set elements
     * @return List of subsets
     */
    public static <T> List<Set<T>> split(Set<T> original, int subsetSize) {

        if (subsetSize <= 0) {
            throw new IllegalArgumentException("Incorrect max size");
        }

        if (original == null || original.isEmpty()) {
            return Collections.emptyList();
        }

        int subsetCount = (int) (Math.ceil((double) original.size() / subsetSize));
        ArrayList<Set<T>> subsets = new ArrayList<Set<T>>(subsetCount);
        Iterator<T> iterator = original.iterator();

        for (int i = 0; i < subsetCount; i++) {
            Set<T> subset = new LinkedHashSet<T>(subsetSize);
            for (int j = 0; j < subsetSize && iterator.hasNext(); j++) {
                subset.add(iterator.next());
            }
            subsets.add(subset);
        }
        return subsets;
    }
}

Related

1. getFirstSubString(String s, Set delimiters)
2. getSubsets(Set set)
3. sub(Set a, Set b)
4. subset(double[] vals, boolean[] select)
5. subset(Set sub, Set sup)
6. subSet(Set nn, T n)