ListsTest.java

/*
 * Copyright (c) 2015-present, Parse, LLC.
 * All rights reserved.
 *
 * This source code is licensed under the BSD-style license found in the
 * LICENSE file in the root directory of this source tree. An additional grant
 * of patent rights can be found in the PATENTS file in the same directory.
 */
package com.parse;

import org.junit.Test;

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

import static org.junit.Assert.assertEquals;

public class ListsTest {

  @Test
  public void testPartition() throws Exception {
    List<Integer> list = new ArrayList<>();
    for (int i = 0; i < 99; i++) {
      list.add(i);
    }
    List<List<Integer>> partitions = Lists.partition(list, 5);
    assertEquals(20, partitions.size());

    int count = 0;
    for (int i = 0; i < 19; i++) {
      List<Integer> partition = partitions.get(i);
      assertEquals(5, partition.size());
      for (int j : partition) {
        assertEquals(count, j);
        count += 1;
      }
    }
    assertEquals(4, partitions.get(19).size());
    for (int i = 0; i < 4; i++) {
      assertEquals(95 + i, partitions.get(19).get(i).intValue());
    }
  }
}