package org.nhooo.example.servlet;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Enumeration;
import javax.servlet.Servlet;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class ContextInitParameter extends HttpServlet implements Servlet {
public ContextInitParameter() {
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
doPost(request, response);
}
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
response.setContentType("text/html");
PrintWriter writer = response.getWriter();
//获取ServletContext的实例
ServletContext context = getServletContext();
//要读取上下文初始化参数，我们可以调用context.getInitParameter()
//并传递要读取的初始化参数的名称。如果命名
//参数不存在，返回值将为null。
//
//在此示例中，我们读取了一个称为LOG.PATH的初始化参数。
String logPath = context.getInitParameter("LOG.PATH");
writer.println("Log Path: " + logPath + "<br/>");
//读取Servlet初始化参数的所有名称。如果
//servlet没有任何空的枚举将被返回。
Enumeration enumeration = context.getInitParameterNames();
while (enumeration.hasMoreElements()) {
String paramName = (String) enumeration.nextElement();
String paramValue = context.getInitParameter(paramName);
writer.println("Context Init Param: [" + paramName + " = " + paramValue + "]<br/>");
}
}
}
