java list集合运算

list集合运算

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.util.ArrayList;
import java.util.List;

public class ListDemo {

	public static void main(String[] args) throws IOException, ClassNotFoundException {
		// TODO Auto-generated method stub
		  List <String> listA = new ArrayList <String>();
		  listA.add("aa");
		  listA.add("bb");
		  listA.add("cc");

		  List <String> listB = new ArrayList <String>();
		  listB.add("cc");
		  listB.add("dd");
		  listB.add("ff");

		  List <String> listC = new ArrayList <String>();

		  listC = deepCopy(listA);

		  //求并集
		  listA.addAll(listB);
		  System.out.println("--并集--" +listA);
		  //--并集--[aa, bb, cc, cc, dd, ff]

		  //交集
		  listA = deepCopy(listC);
		  listA.retainAll(listB);
		  System.out.println("--交集--" +listA);
		  //--交集--[cc]

		  //差集
		  listA = deepCopy(listC);
		  listA.removeAll(listB);
		  System.out.println("--差集--" +listA);
		  //--差集--[aa, bb]

		  //无重复并集
		  listA = deepCopy(listC);
		  listA.removeAll(listB);
		  listA.addAll(listB);
		  System.out.println("--无重复并集--" +listA);
		  //--无重复并集--[aa, bb, cc, dd, ff]

	}

	public static <T> List<T> deepCopy(List<T> src) throws IOException, ClassNotFoundException {
		/**
		 * 深拷贝
		 */
	    ByteArrayOutputStream byteOut = new ByteArrayOutputStream();
	    ObjectOutputStream out = new ObjectOutputStream(byteOut);
	    out.writeObject(src);  

	    ByteArrayInputStream byteIn = new ByteArrayInputStream(byteOut.toByteArray());
	    ObjectInputStream in = new ObjectInputStream(byteIn);
	    @SuppressWarnings("unchecked")
	    List<T> dest = (List<T>) in.readObject();
	    return dest;
	}
}