1. 集合操作

import java.util.ArrayList;
import java.util.Collection;

import org.apache.commons.collections.CollectionUtils;

import com.google.common.collect.Lists;

public class CollectionUtilsIntro {
    public static void main(String[] args) {
        ArrayList<String> array1 = Lists.newArrayList("a", "b", "c");
        ArrayList<String> array2 = Lists.newArrayList("c", "d", "e");

        //并集
        Collection<String> union = CollectionUtils.union(array1, array2);
        //交集
        Collection<String> intersection = CollectionUtils.intersection(array1, array2);
        //交集的补集
        Collection<String> disjunction = CollectionUtils.disjunction(array1, array2);
        //集合相减
        Collection<String> subtract = CollectionUtils.subtract(array1, array2);

        System.out.println("并集：" + union);
        System.out.println("交集" + intersection);
        System.out.println("交集的补集" + disjunction);
        System.out.println("集合相减" + subtract);
    }
}

执行结果：

并集：[a, b, c, d, e]
交集：[c]
交集的补集：[a, b, d, e]
集合相减：[a, b]

2. 分片操作

import java.util.ArrayList;

import com.google.common.collect.Lists;

public class CollectionUtilsIntro {
    public static void main(String[] args) {
        ArrayList<String> array1 = Lists.newArrayList("a", "b", "c");

        //分成了两个集合，没一个集合又可以单独的去处理。
        Lists.partition(array1, 2).forEach(r -> {
            System.out.println(r);
            System.out.println("----");
        });
    }
}

执行结果：

[a, b]
----
[c]
----