Map的排序问题

import java.util.HashMap;  import java.util.LinkedHashMap;  import java.util.Map;  import java.util.TreeMap;    public class Test {  public static void main(String[] args) {      Map tree = new TreeMap();      Map linked = new LinkedHashMap();      Map hash = new HashMap();      System.out.println("tree :"+buildMap(tree));      System.out.println("link :"+buildMap(linked));      System.out.println("hash :"+buildMap(hash));  }  private static Map buildMap(Map map){      map.put("0", "a");      map.put("e", "b");      map.put("4", "s");      map.put("3", "c");      return map;  }  }  

?输出结果：

Java代码 tree :{0=a, 3=c, 4=s, e=b}  link :{0=a, e=b, 4=s, 3=c}  hash :{3=c, 0=a, 4=s, e=b}  

?

由此可见：?
HashMap是按照HashCode 排序，莫名其妙的顺序。?
TreeMap是按照自身的顺序排序，比如数字的话，按照数字升序，ascII等。?
LinkedHashMap是按照先进先出的顺序。