java - servlet中的文件读取问题

Question

我必须使用 servlet 读取文件。这是我正在使用的代码。但文件未使用此代码读取。始终打印 File contains null value-------------- ----:

protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    try {
        response.setContentType("text/html");
        String filename = "D/root.properties";
        ServletContext context = getServletContext();

        InputStream inp = context.getResourceAsStream(filename);
        if (inp != null) {
            InputStreamReader isr = new InputStreamReader(inp);
            BufferedReader reader = new BufferedReader(isr);
            PrintWriter pw = response.getWriter();

            String text = "";

            while ((text = reader.readLine()) != null) {                     
            }
        } else {
            System.out.println("File contains null value-----------------");
        }
    } catch(Exception e) {
        System.out.println("Rxpn............................................."+e);
    }
}

protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    doGet(request,response);
}

Answer 1

javadoc救援:

java.net.URL getResource(java.lang.String path) throws java.net.MalformedURLException

Returns a URL to the resource that is mapped to the given path.

The path must begin with a / and is interpreted as relative to the current context root, or relative to the /META-INF/resources directory of a JAR file inside the web application's /WEB-INF/lib directory. This method will first search the document root of the web application for the requested resource, before searching any of the JAR files inside /WEB-INF/lib. The order in which the JAR files inside /WEB-INF/lib are searched is undefined.

如果您想从 Web 应用程序中读取资源，请使用上述路径。如果你想从文件系统读取，使用文件 IO(和正确的文件名):new FileInputStream("D:/root.properties")