我在客户端中这么写

socket = new Socket(ip, 23456);

oos = new ObjectOutputStream(socket.getOutputStream());

oos.writeObject(transfer);

oos.flush();

服务器端学老师这么写

ois = new ObjectInputStream(socket.getInputStream());

CammandTransfer transfer = (CammandTransfer) ois.readObject();

但是出现了这种错误

java.lang.ClassNotFoundException: com.android.yunnotes.CammandTransfer

at java.net.URLClassLoader$1.run(URLClassLoader.java:372)

at java.net.URLClassLoader$1.run(URLClassLoader.java:361)

at java.security.AccessController.doPrivileged(Native Method)

at java.net.URLClassLoader.findClass(URLClassLoader.java:360)

at java.lang.ClassLoader.loadClass(ClassLoader.java:424)

at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308)

at java.lang.ClassLoader.loadClass(ClassLoader.java:357)

at java.lang.Class.forName0(Native Method)

at java.lang.Class.forName(Class.java:340)

at java.io.ObjectInputStream.resolveClass(ObjectInputStream.java:626)

at java.io.ObjectInputStream.readNonProxyDesc(ObjectInputStream.java:1613)

at java.io.ObjectInputStream.readClassDesc(ObjectInputStream.java:1518)

at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1774)

at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1351)

at java.io.ObjectInputStream.readObject(ObjectInputStream.java:371)

at com.myserver.main.ServerThread.run(ServerThread.java:23)

23行就是那句CammandTransfer transfer = (CammandTransfer) ois.readObject();

这是什么问题呢

补充com.android.yunnotes是客户端的包，com.myserver.main是服务器的包