java的throw Eeception和throws Eeception有什么区别

Question

http://www.shu.edu.cn/campus/java/chp8.html
异常的教程throws用 来 标 明 一 个 成 员 函 数 可 能 抛 出 的 各 种“ 异 常”。throw语 句 用 来 明 确 地 抛 出 一 个“ 异 常”。 
class ThrowsDemo { 
static void procedure( ) throws IllegalAccessException   //throws用在函数声明
{ 
     System.out.println("inside procedure");
     throw new IllegalAccessException("demo");         //throw 用在这函数体内
} 
public static void main(String args[]) 
{
 try { 
    procedure( ); 
    } catch (IllegalAccessException e) 
    { 
   System.out.println("caught " + e); 
    } 
   } 
}