java中數組list map兩者之間的互轉介紹

轉換關係:

import java.util.ArrayList; 
import java.util.Arrays; 
import java.util.HashMap; 
import java.util.List; 
import java.util.Map; 

public class Convert{
    static public void main(String[] args) throws UnsupportedEncodingException {
        //1.數組轉換爲list，map
        String[] arr = {"123","456","789","123"};
        List<String> list = Arrays.asList(arr);
        //數組轉換爲map,一維數組時，奇數爲key,偶數爲value,奇數個元素，最後一個舍掉
        //.二維數組當作兩個一維數組
        Map map = MapUtils.putAll(new HashMap(), arr);

        String[][] ss = {{"a","b","e"},{"c","d","f"}};
        MapUtils.debugPrint(System.out,arr,map);
        MapUtils.putAll(map, arr);
        MapUtils.debugPrint(System.out,arr,map);
        MapUtils.putAll(map, ss);
        MapUtils.verbosePrint(System.out,arr,MapUtils.invertMap(map));

//list 轉換爲arr
        List<String> ls = new ArrayList<String>();
        ls.add("wch");
        ls.add("name");
        String[] as = (String[]) ls.toArray();

    }
}