[java新手] IO和网络编程的问题

Question

做网络编程的练习，用socket连接 传输文件，目的是把一个文件传到服务端保存下来
测试结果完全正常，文件也传输完成，但是catch捕捉到了异常？？？！
当运行服务端时候客户端catch报错，当运行客户端时候服务端catch报错 0.0
代码如下

修改了下代码，我把输出换成e.printStackTrace()打印了，还是这样 结果是实现了的，测试通过，但是有捕获到异常

import java.io.*;
import java.net.InetAddress;
import java.net.ServerSocket;
import java.net.Socket;

import org.junit.Test;

public class 网络编程_上传 {
    public static String ClientInteAddress = "127.0.0.1";
    public static String str = "9000";
    public static String ServerFileAddress = "E:\\111.xls";
    public static String ClientFileAddress = "D:\\15916\\下载\\111.xls";

    @Test//服务器
    public void server() {
        ServerSocket sss = null;
        Socket sk = null;
        InputStream is = null;
        BufferedInputStream bis = null;
        FileOutputStream fos = null;

        try {
            sss = new ServerSocket(new Integer(str));
            sk = sss.accept();
            is = sk.getInputStream();
            bis = new BufferedInputStream(is);
            fos = new FileOutputStream(ServerFileAddress);

            int buffi = 0;
            byte [] by = new byte[1024];

            while ((buffi = bis.read(by)) != -1) {
                fos.write(by);
            }

            fos.close();
            bis.close();
            sk.close();
            sss.close();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
                try {
                    if (fos != null) {fos.close();}
                    if (bis != null) bis.close();
                    if (sk != null) sk.close();
                    if (sss != null) sss.close();
                } catch (IOException e) {
                    System.out.println("服务器报错啦！：关闭流出错");
                }
            }

    }

    @Test//客户端
    public void client() {
        Socket sk = null;
        OutputStream os = null;
        BufferedOutputStream bos = null;
        FileInputStream fis = null;

        try {
            sk = new Socket(InetAddress.getByName(ClientInteAddress), new Integer(str));
            os = sk.getOutputStream();
            bos = new BufferedOutputStream(os);
            fis = new FileInputStream(ClientFileAddress);

            int buffi = 0;
            byte [] by = new byte[1024];
            while ((buffi = fis.read(by)) != -1) {
                bos.write(by);
            }

            fis.close();
            bos.close();
            sk.close();
        } catch (NumberFormatException | IOException e) {
            e.printStackTrace();
        } finally {
            try {
                if (sk != null) sk.close();
                if (fis != null) fis.close();
                if (bos != null) bos.close();

            } catch (IOException e) {
                System.out.println("客户端报错啦！：关闭流出错");
            }
        }

    }

}

Answer 1

那个捕捉的IO异常怎么来的，我不清楚。而且在我把catch内容换为输出之前，报错有:JVM绑定错误（socket赋值行） 连接错误