Question

我正在使用hibernate和tomcat。我所做的是创建一个具有文件输入的表单。在servlet中我想将该文件转换为byte []。但是当我想创建de File时，没有目录：它只保存图像的名称，而不是路径。这是错误：

java.io.FileNotFoundException：oldi.png（没有这样的文件或目录）在java.io.FileInputStream.open（Native Method）at java.io.FileInputStream。（FileInputStream.java:138）at control.servlets.AddGenericItem.doPost（AddGenericItem.java:46）at javax.servlet.http.HttpServlet.service（HttpServlet.java:647）at at javax.servlet.http.HttpServlet.service（HttpServlet.java:728）at at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter（ApplicationFilterChain.java:305）在 org.apache.catalina.core.ApplicationFilterChain.doFilter（ApplicationFilterChain.java:210）在 org.apache.catalina.core.StandardWrapperValve.invoke（StandardWrapperValve.java:222）在 org.apache.catalina.core.StandardContextValve.invoke（StandardContextValve.java:123）在 org.apache.catalina.authenticator.AuthenticatorBase.invoke（AuthenticatorBase.java:472）在 org.apache.catalina.core.StandardHostValve.invoke（StandardHostValve.java:171）在 org.apache.catalina.valves.ErrorReportValve.invoke（ErrorReportValve.java:99）在 org.apache.catalina.valves.AccessLogValve.invoke（AccessLogValve.java:947）在 org.apache.catalina.core.StandardEngineValve.invoke（StandardEngineValve.java:118）在 org.apache.catalina.connector.CoyoteAdapter.service（CoyoteAdapter.java:408）在 org.apache.coyote.http11.AbstractHttp11Processor.process（AbstractHttp11Processor.java:1009）在 org.apache.coyote.AbstractProtocol $ AbstractConnectionHandler.process（AbstractProtocol.java:589）在 org.apache.tomcat.util.net.JIoEndpoint $ SocketProcessor.run（JIoEndpoint.java:310）在 java.util.concurrent.ThreadPoolExecutor.runWorker（ThreadPoolExecutor.java:1145）在 java.util.concurrent.ThreadPoolExecutor中的$ Worker.run（ThreadPoolExecutor.java:615）在java.lang.Thread.run（Thread.java:724）

HTML：

<tr>
    <td>
        <font class="text_title">Image: </font>
    </td>
    <td>
        <input name="image" type="file">
    </td>
</tr>

<tr>
    <td>
        <input type="submit" value="submit" name="ctl00$MainContent$RegisterUserWizard$CreateUserStepContainer$CreateButton"
               id="ctl00_MainContent_RegisterUserWizard_CreateUserStepContainer_CreateButton"
               style="border-width:0px;">
    </td>
</tr>

的Servlet

public class AddGenericItem extends HttpServlet {
    @Override
    protected void doPost(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse)
            throws ServletException, IOException {

//        HttpSession session = httpServletRequest.getSession();
        DatabaseManager databaseManager = new DatabaseManager();

        String name = httpServletRequest.getParameter("name");
        String description = httpServletRequest.getParameter("description");
        float price = Float.parseFloat(httpServletRequest.getParameter("price"));

        File image = new File(httpServletRequest.getParameter("image"));
        byte[] imageArray = new byte[(int) image.length()];
        try {
            FileInputStream fileInputStream = new FileInputStream(image);
            fileInputStream.read(imageArray);
            fileInputStream.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
        Admin admin = (Admin) httpServletRequest.getSession().getAttribute("user");
        Brand brand = admin.getBrand();

        GenericItem genericItem = new GenericItem(name, description, imageArray, price,brand);

        GenericItemDAO genericItemDAO = databaseManager.getGenericItemDAO();

        genericItemDAO.beginTransaction();
        genericItemDAO.save(genericItem);

        try {
            genericItemDAO.commitTransaction();
        } catch (DatabaseAccessFailException e) {
            e.getStackTrace();
        } finally {
            httpServletResponse.sendRedirect("/adminPages/items.jsp");
        }
    }

    @Override
    protected void doGet(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse)
            throws ServletException, IOException {

    }

    @Override
    protected void doDelete(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse)
            throws ServletException, IOException {

    }

}

Answer 1

我希望您正在处理文件上传。

问题出在以下几行：

FileInputStream fileInputStream = new FileInputStream(image);

Servlet在服务器上查找文件以读取它，但那时它不会在那里。

使用Apache提供的Commons Fileupload library，可以轻松地为您的servlet和Web应用程序添加强大，高性能的文件上载功能。

查找完整代码here和here以及here

java.io.FileNotFoundException :(没有这样的文件或目录） - 使用servlet

1 个答案: