Question

我想从我的Java本地应用程序上传一个包含文件到服务器的对象。我的计划是在tomcat上运行的servlet将使用ObjectInputStream方法中的doGet获取对象。但我得到一个EOFE xception`。

这是客户端代码

import java.io.*;
import java.net.*;
public class Client {
    public static void main(String[] args) throws IOException {
        FileInputStream inputStream = new FileInputStream("c:\\rafi.txt");
        ByteArrayOutputStream output = new ByteArrayOutputStream();
        byte[] buffer = new byte[1024];
        int n = 0;
        while (-1 != (n = inputStream.read(buffer))) {
            output.write(buffer, 0, n);
        }
        inputStream.close();
        File2 c2 = new File2(buffer);
        URL url = new URL("http://localhost:8080/servertest/Server");
        URLConnection cnx = url.openConnection();
        cnx.setDoInput(true);
        cnx.setDoOutput(true);
        cnx.setRequestProperty("Content-Type", "application/octet-stream");
        InputStream in = cnx.getInputStream();
        OutputStream out = cnx.getOutputStream();
        cnx.connect();
        ObjectOutputStream oos = new ObjectOutputStream(out);
        oos.writeObject(c2);
        oos.flush();
        oos.close();
        ObjectInputStream ois = new ObjectInputStream(in);
        boolean readBoolean = ois.readBoolean();
        System.out.println(readBoolean);
        ois.close();
        in.close();
        out.close();
    }
}

这是服务器的servlet

import java.io.*;
import javax.servlet.*;
@WebServlet("/Server")
public class Server extends HttpServlet {
    private static final long serialVersionUID = 1L;
    public Server() {
        super();
    }
    protected void doGet(HttpServletRequest req, HttpServletResponse res)
            throws ServletException, IOException {
        InputStream in = req.getInputStream();
        OutputStream out = res.getOutputStream();
        ObjectOutputStream oos = new ObjectOutputStream(out);
        ObjectInputStream ois = new ObjectInputStream(in);

        File2 data_in;
        try {
            data_in = (File2) ois.readObject();
            byte[] a = new byte[data_in.mybytearray.length];
            System.arraycopy(data_in.mybytearray, 0, a, 0,data_in.mybytearray.length);
            System.out.println(a.toString());
            oos.writeBoolean(true);
        } catch (ClassNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
            oos.writeBoolean(false);
        }
        finally{
            oos.close();
            }

        res.setContentType("java-internal/" + File2.class.getName());
        in.close();
    }
}

当我调试服务器端并运行客户端时，我在此行中获得异常

ObjectOutputStream oos = new ObjectOutputStream(out);

这是我得到的错误

SEVERE: Servlet.service() for servlet [test1.Server] in context with path [/servertest] threw exception
java.io.EOFException
    at java.io.ObjectInputStream$PeekInputStream.readFully(Unknown Source)
    at java.io.ObjectInputStream$BlockDataInputStream.readShort(Unknown Source)
    at java.io.ObjectInputStream.readStreamHeader(Unknown Source)
    at java.io.ObjectInputStream.<init>(Unknown Source)
    at test1.Server.doGet(Server.java:38)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:304)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:240)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:164)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:462)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:164)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
    at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:562)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:395)
    at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:250)
    at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:188)
    at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:166)
    at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:302)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
    at java.lang.Thread.run(Unknown Source)

我看到了question，但我没有帮助我。我正在使用tomcat 7。

Answer 1

InputStream in = cnx.getInputStream();
OutputStream out = cnx.getOutputStream();

URLConnection#getInputStream()会立即将HTTP请求发送到服务器以检索响应正文。在编写代码的过程中，这样就会在之前发生，你已经将任何位写入HTTP请求体。因此服务器端的EOFException。

您需要在之后通过URLConnection#getInputStream() 询问HTTP响应正文，并将必要的数据写入HTTP请求正文。这是一个重写：

URLConnection connection = new URL("http://localhost:8080/servertest/Server").openConnection(); connection.setDoOutput(true); connection.setRequestProperty("Content-Type", "application/octet-stream"); ObjectOutputStream oos = new ObjectOutputStream(connection.getOutputStream()); oos.writeObject(c2); oos.close(); ObjectInputStream ois = new ObjectInputStream(connection.getInputStream()); boolean readBoolean = ois.readBoolean(); ois.close(); System.out.println(readBoolean);

此外，由于您基本上是在发送HTTP POST请求，因此您需要在servlet的doPost()方法而不是doGet()方法中处理此问题。

无关具体问题：这不是通过HTTP发送文件的最佳方式。虽然它可能有用，但这与Java序列化机制非常紧密相关。我建议改为发送HTTP multipart/form-data请求。这可以通过客户端Apache HttpComponents Client和服务器端Apache Commons FileUpload来实现。这样，servlet可以重复用于其他目的，例如前面带有<input type="file">的HTML表单。此外，客户端可以通过这种方式重新上传文件到其他HTTP网站。

Answer 2

我在客户端解决了这个问题：

HttpURLConnection cnx = (HttpURLConnection) new URL("http://localhost:8080/web").openConnection();
cnx.setRequestMethod("PUT");

将序列化数据发送到servlet时的java.io.EOFException

2 个答案: