package cn.sxt.collection;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;
public class TestIterator {
public static void main(String[] args) {
testIteratorList();
// testIteratorSet();
// testIteratorMap();
testRemove();
}
public static void testIteratorList() {
List<String> list = new ArrayList<String>();
list.add("ad");
list.add("bb");
list.add("cc");
//用迭代器遍历List
for(Iterator<String> iterator = list.iterator();iterator.hasNext();){
String temp = iterator.next();
System.out.println(temp);
}
}
public static void testIteratorSet(){
Set<String> set = new HashSet<String>();
set.add("aa");
set.add("bb");
set.add("cc");
//使用iterator遍历Set
for(Iterator<String> iter = set.iterator(); iter.hasNext();){
String temp = iter.next();
System.out.println(temp);
}
}
public static void testIteratorMap(){
Map<Integer, String> map1 = new HashMap<>();
map1.put(100,"a");
map1.put(200,"b");
map1.put(300,"c");
//第一种遍历Map的方式
Set<Entry<Integer, String>> s = map1.entrySet();
for(Iterator<Entry<Integer, String>> iter = s.iterator(); iter.hasNext();){
Entry<Integer, String> temp = iter.next();
System.out.println(temp.getKey() + "---" + temp.getValue());
}
System.out.println("===========================");
//第二种遍历Map的方式
Set<Integer> keySet = map1.keySet();
for(Iterator<Integer> iter = keySet.iterator(); iter.hasNext();){
Integer key = iter.next();
System.out.println(key + "---" + map1.get(key));
}
}
//测试边遍历，边删除
public static void testRemove(){
List<String> list = new ArrayList<>();
for(int i=0;i<20;i++){
list.add("gao"+i);
}
for(int i=0;i<list.size();i++){
String temp = list.get(i);
if(temp.endsWith("2")){
list.remove(i);
}
System.out.println(list.size());
System.out.println(list.get(i));
}
}
}
