servlet初始化问题

我看书上说：Servlet只会初始化一次，在初始化的时候容器为servlet建立了ServletConfig和ServletContext。容器去web.xml中读取初始化参数，将初始化参数传递给ServletConfig和ServletContext，然后再将ServletConfig和ServletContext传递给servlet的init()方法。
假如现在有一个email项目，然后里面有一个WEB-INF/web.xml

Xml代码
<?xml version="1.0" encoding="UTF-8"?> 
<web-app version="2.4"   
    xmlns="http://java.sun.com/xml/ns/j2ee"   
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"   
    xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee   
    http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd"> 
      
  <servlet> 
    <description>This is the description of my J2EE component</description> 
    <display-name>This is the display name of my J2EE component</display-name> 
    <servlet-name>email</servlet-name> 
    <servlet-class>Email</servlet-class> 
     <init-param> 
    <param-name>myEmail</param-name> 
    <param-value>[e-mail]</param-value> 
    </init-param> 
      
    <init-param> 
    <param-name>adminEmail</param-name> 
    <param-value>[e-mail]</param-value> 
    </init-param> 
  </servlet> 
    
    <servlet-mapping> 
    <servlet-name>email</servlet-name> 
    <url-pattern>/email.do</url-pattern> 
     
  </servlet-mapping> 
 
<context-param> 
<param-name>managerEmail</param-name> 
<param-value>[e-mail]</param-value> 
</context-param> 
</web-app> 

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.4"
xmlns="http://java.sun.com/xml/ns/j2ee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee
http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">

  <servlet>
    <description>This is the description of my J2EE component</description>
    <display-name>This is the display name of my J2EE component</display-name>
    <servlet-name>email</servlet-name>
    <servlet-class>Email</servlet-class>
     <init-param>
    <param-name>myEmail</param-name>
    <param-value>[e-mail]</param-value>
    </init-param>
   
    <init-param>
    <param-name>adminEmail</param-name>
    <param-value>[e-mail]</param-value>
    </init-param>
  </servlet>
 
    <servlet-mapping>
    <servlet-name>email</servlet-name>
    <url-pattern>/email.do</url-pattern>
  
  </servlet-mapping>

<context-param>
<param-name>managerEmail</param-name>
<param-value>[e-mail]</param-value>
</context-param>
</web-app>


然后一个servlet----Email.java

Java代码
public class Email extends HttpServlet {  
 
      
    public void doGet(HttpServletRequest request, HttpServletResponse response)  
            throws ServletException, IOException {  
 
        response.setContentType("text/html");  
        PrintWriter out = response.getWriter();  
        out.println("My Email is "+getServletConfig().getInitParameter("myEmail")+"<br>");  
        out.println("Admin\'s Email is "+getServletConfig().getInitParameter("adminEmail")+"<br>");  
        out.println("Manager\'s Email is "+getServletContext().getInitParameter("managerEmail")+"<br>");  
    }  
 
      
} 

public class Email extends HttpServlet {


public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {

response.setContentType("text/html");
PrintWriter out = response.getWriter();
out.println("My Email is "+getServletConfig().getInitParameter("myEmail")+"<br>");
out.println("Admin\'s Email is "+getServletConfig().getInitParameter("adminEmail")+"<br>");
out.println("Manager\'s Email is "+getServletContext().getInitParameter("managerEmail")+"<br>");
}


}

如果我修改了web.xml中

<init-param>和<context-param>的<param-value>值，书上说只能项目重部署的时候才能看见这个改变，可是我直接刷新几次网页（强调：一定要是几次）就看到改动的值了，不明白为什么，难道不用重部署，servlet也可以再次初始化，再次去读web.xml的初始化参数吗？
在eclipse里,你只改要代码或配置文件,然后保存,它会自动编译的,会重新启动tomcat的,不信,你保存好,注意看一下,eclipse里的控制台,肯定会有重启信息的