servletConfig

servletConfig--代表当前servlet在web.xml中的配置信息

String getServletName() – 获取当前servlet在web.xml取的名字

 String

getInitParameter(String name) 获取当前servlet指定名称的初始化参数的值
          Returns a String containing the value of the named initialization parameter, or null if the parameter does not exist.

 Enumeration

getInitParameterNames()获取当前servlet所有初始化参数的名字组成的枚举
          Returns the names of the servlet's initialization parameters as an Enumeration of String objects, or an empty Enumeration if the servlet has no initialization parameters.

ServletContext

getServletContext() 获取代表当前web应用的servletContext对象
          Returns a reference to the ServletContext in which the caller is executing

配置web.xml 设置init-param

<servlet>
    <servlet-name>SConfigServlet</servlet-name>
    <servlet-class>com.itheima.SConfigServlet</servlet-class>
    <init-param>
        <param-name>name1</param-name>
        <param-value>value1</param-value>
    </init-param>
    <init-param>
        <param-name>encode</param-name>
        <param-value>utf-8</param-value>
    </init-param>
  </servlet>

 使用方法

        ServletConfig config = this.getServletConfig();
        //--获取当前Servlet 在web.xml中配置的名称
        String sName = config.getServletName();
        System.out.println(sName);
        //--获取当前Servlet中配置的初始化参数
        String value = config.getInitParameter("name2");
        System.out.println(value);
        
        Enumeration enumration = config.getInitParameterNames();
        while(enumration.hasMoreElements()){
            String name = (String) enumration.nextElement();
            String value = config.getInitParameter(name);
            System.out.println(name+":"+value);
                }
原文地址:https://www.cnblogs.com/superPerfect/p/4296306.html