一个添加了若干键值对的 TreeMap 如何获取它的 前十个元素，11-20的元素？

Question

String abc[] = {"e","d","c","b","a","f","g","h","i","j","k",
"l","m","n","o","p","q","r","s","t","u","v","w","x","y","z"};
int xyz[] = {5,4,3,2,1,26,25,24,23,22,21,20,19,18,17,16,15,14,13,12,11,10,9,8,7,6}; 

Map map = new TreeMap();for(int i=0; i<xyz.length; i++){
map.put(xyz[i], abc[i]);
}System.out.println(map);

Answer 1

能不能 把这个co 转成List??
就可以用 list.get(int index) 了

Answer 2

获得11-20个元素的方法：
Set entries = map.entrySet();
Iterator it = null;
if (entries != null)
it = entries.iterator();

for(int k=1; it.hasNext();k++){
Map.Entry entry = (Map.Entry) it.next();
int key = (Integer) entry.getKey();
String value = entry.getValue().toString();
if(k>10)
System.out.println("key:" + key + "    value:" + value);
}获得前十只要在循环里面写上k<=10 ,sysout ,然后break就行了！注意：TreeMap 得到的是已经排序完的数据，如果想按照put的先后顺序原样输出的话就可以这样写：
Map map = new java.util.LinkedHashMap();

Answer 3

我插到一个方法 collection.toArray()String abc[] = {"e","d","c","b","a","f","g","h","i","j","k",
        "l","m","n","o","p","q","r","s","t","u","v","w","x","y","z"};
int xyz[] = {5,4,3,2,1,26,25,24,23,22,21,20,19,18,17,16,15,14,13,12,11,10,9,8,7,6}; 
    
Map map = new TreeMap();for(int i=0; i<xyz.length; i++){
    map.put(xyz[i], abc[i]);
}System.out.println(map); Collection co = map.values();
Object[] a = co.toArray();
System.out.println("0-----9");
for(int i=0; i<10; ++i)
System.out.print(a[i]);

System.out.println();
System.out.println("10----19");

for(int i=10; i<20; ++i)
System.out.print(a[i]);
System.out.println();