创建一个命名为ServletContextFile的servlet:
import java.io.IOException;
import java.util.Properties;
import javax.servlet.ServletConfig;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.omg.CORBA_2_3.portable.InputStream;
public class ServletContextFile extends HttpServlet {
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
}
@Override
public void init(ServletConfig config) throws ServletException {
//获得ServletContext对象
ServletContext sc=config.getServletContext();
//获得工程Webroot下文件的绝对路径D:\Program Files\Apache Software Foundation\Tomcat 7.0_Tomcat70\webapps\servlet_demo\ContextFileTest.propertise
//getRealPath的参数内容不会被校验,只有真正要用这个路径时才知道路径对不对
String path=sc.getRealPath("ContextFileTest.properties");
String path1=sc.getRealPath("/upload");
System.out.println(path);
System.out.println(path1);
//获得 工程目录WEBroot下文件的第一个/代表根目录
java.io.InputStream in= sc.getResourceAsStream("/WEB-INF/ContextFileTest.properties");
Properties prop=new Properties();
try {
prop.load(in);
System.out.println(prop.get("key"));
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
在WebRoot目录下new一个文件命名为ContextFileTest.properties内容如下:
key=test
配置web.xml文件:
<servlet>
<servlet-name>ServletContextFile</servlet-name>
<servlet-class>ServletContextFile</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>ServletContextFile</servlet-name>
<url-pattern>/ServletContextFile</url-pattern>
</servlet-mapping>
在浏览器上输入:http://localhost:8080/servlet_demo/ServletContextFile
输出效果:
文件的目录结构如下: