importjava.util.Set;importjava.util.List;importjava.util.HashSet;importjava.util.TreeSet;importjava.util.Iterator;importjava.util.ArrayList;importjava.util.LinkedList;public classGAGA {public static voidmain(String args[]) {

getList();

}//获取两个ArrayList的差集、交集、去重并集(数据量大小不限制)

private static voidgetList() {

List firstArrayList = new ArrayList();

List secondArrayList = new ArrayList();

List defectList = new ArrayList();//差集List

List collectionList = new ArrayList();//交集List

List unionList = new ArrayList();//去重并集List

try{

firstArrayList.add("3");

firstArrayList.add("5");

firstArrayList.add("45");

firstArrayList.add("4");

firstArrayList.add("3");

secondArrayList.add("33");

secondArrayList.add("51");

secondArrayList.add("5");

secondArrayList.add("4");

secondArrayList.add("13");//获取差集

defectList =receiveDefectList(firstArrayList, secondArrayList);

Iterator defectIterator =defectList.iterator();

System.out.println("===================差集===================");while(defectIterator.hasNext()) {

System.out.println(defectIterator.next());

}//获取交集

collectionList =receiveCollectionList(firstArrayList, secondArrayList);

Iterator collectionIterator =collectionList.iterator();

System.out.println("===================交集===================");while(collectionIterator.hasNext()) {

System.out.println(collectionIterator.next());

}//获取去重并集

unionList =receiveUnionList(firstArrayList, secondArrayList);

Iterator unionIterator =unionList.iterator();

System.out.println("===================去重并集===================");while(unionIterator.hasNext()) {

System.out.println(unionIterator.next());

}

}catch(Exception e) {

e.printStackTrace();

}

}/*** @方法描述：获取两个ArrayList的差集

*@paramfirstArrayList 第一个ArrayList

*@paramsecondArrayList 第二个ArrayList

*@returnresultList 差集ArrayList*/

public static List receiveDefectList(List firstArrayList, ListsecondArrayList) {

List resultList = new ArrayList();

LinkedList result = new LinkedList(firstArrayList);//大集合用linkedlist

HashSet othHash = new HashSet(secondArrayList);//小集合用hashset

Iterator iter = result.iterator();//采用Iterator迭代器进行数据的操作

while(iter.hasNext()){if(othHash.contains(iter.next())){

iter.remove();

}

}

resultList= new ArrayList(result);returnresultList;

}/*** @方法描述：获取两个ArrayList的交集

*@paramfirstArrayList 第一个ArrayList

*@paramsecondArrayList 第二个ArrayList

*@returnresultList 交集ArrayList*/

public static List receiveCollectionList(List firstArrayList, ListsecondArrayList) {

List resultList = new ArrayList();

LinkedList result = new LinkedList(firstArrayList);//大集合用linkedlist

HashSet othHash = new HashSet(secondArrayList);//小集合用hashset

Iterator iter = result.iterator();//采用Iterator迭代器进行数据的操作

while(iter.hasNext()) {if(!othHash.contains(iter.next())) {

iter.remove();

}

}

resultList= new ArrayList(result);returnresultList;

}/*** @方法描述：获取两个ArrayList的去重并集

*@paramfirstArrayList 第一个ArrayList

*@paramsecondArrayList 第二个ArrayList

*@returnresultList 去重并集ArrayList*/

public static List receiveUnionList(List firstArrayList, ListsecondArrayList) {

List resultList = new ArrayList();

Set firstSet = new TreeSet(firstArrayList);for(String id : secondArrayList) {//当添加不成功的时候 说明firstSet中已经存在该对象

firstSet.add(id);

}

resultList= new ArrayList(firstSet);returnresultList;

}

}