Java导入语句

java version “1.6.0_20”
Java(TM) SE Runtime Environment (build 1.6.0_20-b02)
Java HotSpot(TM) Client VM (build 16.3-b01,mixed mode,sharing)

为什么在以下之间有区别？

情况1：

import java.util.*;

情况2：

import java.util.*;
import java.util.Arrays;
import java.util.List;

为什么第一种情况不包括第二种情况？

当我明确导入数组和列表时,代码只会编译.

码：

import java.util.*;
import java.util.Arrays;
import java.util.List;

public class Test {
        public static void main (String[] args) {
                List<Integer> i = new ArrayList(Arrays.asList(1,2,3,4,5,6,7,8,9,10));
                List<Integer> j = new ArrayList();
                ListIterator<Integer> n = i.listIterator(i.size());

                while(n.hasPrevious()) {
                        j.add(n.previous());
                }

                println(j);

        }

        static void println(Object o) {
                System.out.println(o);
        }

        static void print(Object o) {
                System.out.print(o);
        }

}

当我注释第二和第三个import语句时,我得到的错误是：

nattyp@debian:~/dev/java$javac Test.java
Test.java:7: cannot find symbol
symbol  : method asList(int,int,int)
location: class Arrays
                List<Integer> i = new ArrayList(Arrays.asList(1,10));
                                                      ^
Note: Test.java uses unchecked or unsafe operations.
Note: Recompile with -Xlint:unchecked for details.
1 error
nattyp@debian:~/dev/java$