ServletConfig

public interface ServletConfig {
    public String getServletName();//获取Servlet在web.xml文件中的配置名称，即<servlet-name>指定的名称
    public ServletContext getServletContext();//用来获取ServletContext对象
    public String getInitParameter(String name);//用来获取在web.xml中配置的初始化参数，通过参数名来获取参数值
    public Enumeration<String> getInitParameterNames();//用来获取在web.xml中配置的所有初始化参数名称

}

<servlet>
        <servlet-name>sf</servlet-name>
        <servlet-class>com.sflik.servlet.HelloServlet</servlet-class>        
        <init-param>
        <param-name>pname</param-name>
        <param-value>pvalue</param-value>
        </init-param>        
    </servlet>

@Override
    public void init(ServletConfig config) throws ServletException {
        System.out.println(config.getInitParameter("pname")); 
        System.out.println(config.getInitParameter("pvalue")); 
        Enumeration e = config.getInitParameterNames();
        while(e.hasMoreElements()){
            System.out.println(e.nextElement());
        }
    }