创建一个servlet命名为ServletContextFile2:
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
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;
public class ServletContextFile2 extends HttpServlet {
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
}
@Override
public void init(ServletConfig config) throws ServletException {
ServletContext sc=config.getServletContext();
//获得classpath下的资源的文件的流,用于ckasspath下的文件发布之后实在/WEB-INF/classes下,所以去指定/WEB-INF/classes/ContextFileTest2.properties
//读取方法一(不常用)
//java.io.InputStream in=sc.getResourceAsStream("/WEB-INF/classes/ContextFileTest2.properties");
//读取方法二(使用类加载器的方式读取classpath下的资源文件,好处:不依赖于ServletContext,任何类都可以获得classpath下的资源文件,不需要再自己指定/WEB-INF/classes)
java.io.InputStream in=this.getClass().getClassLoader().getResourceAsStream("ContextFileTest2.properties");
Properties prop=new Properties();
try {
prop.load(in);
System.out.println(prop.get("key2"));
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
在src下new一个文件命名为ContextFileTest2.properties:
key2=test2
配置web.xml文件:
<servlet>
<servlet-name>ServletContextFile2</servlet-name>
<servlet-class>ServletContextFile2</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>ServletContextFile2</servlet-name>
<url-pattern>/ServletContextFile2</url-pattern>
</servlet-mapping>
在浏览器中输入:http://localhost:8080/servlet_demo/ServletContextFile2
输出效果:
文件目录结构: