这个 SocketException 在 ObjectInputStream.readObject() 方法中抛出,是什么原因导致这个异常?另外,客户端和服务端socket的soTimeout的值都为0,KeepAlive的值为false。
{2012-01-09 17:44:13,908} ERROR java.net.SocketException: Connection timed out
at java.net.SocketInputStream.socketRead0(Native Method)
at java.net.SocketInputStream.read(SocketInputStream.java:146)
at sun.security.ssl.InputRecord.readFully(InputRecord.java:312)
at sun.security.ssl.InputRecord.read(InputRecord.java:350)
at sun.security.ssl.SSLSocketImpl.readRecord(SSLSocketImpl.java:809)
at sun.security.ssl.SSLSocketImpl.readDataRecord(SSLSocketImpl.java:766)
at sun.security.ssl.AppInputStream.read(AppInputStream.java:94)
at sun.security.ssl.AppInputStream.read(AppInputStream.java:69)
at java.io.ObjectInputStream$PeekInputStream.peek(ObjectInputStream.java:2265)
at java.io.ObjectInputStream$BlockDataInputStream.peek(ObjectInputStream.java:2558)
at java.io.ObjectInputStream$BlockDataInputStream.peekByte(ObjectInputStream.java:2568)
at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1314)
at java.io.ObjectInputStream.readObject(ObjectInputStream.java:368)
从关于 setSoTimeout 方法的 JAVA API 文档中,如果该方法设置为非零值,则当时间到时,仅抛出 SocketTimeoutException,而不是 SocketException:Connection timed out,因此,此异常不应与 setSotimeoutMethod 相关.
public void setSoTimeout(int timeout) throws SocketException
Enable/disable SO_TIMEOUT with the specified timeout, in milliseconds. With this
option set to a non-zero timeout, a read() call on the InputStream associated with
this Socket will block for only this amount of time. If the timeout expires, a
java.net.SocketTimeoutException is raised, though the Socket is still valid. The
option must be enabled prior to entering the blocking operation to have effect. The
timeout must be > 0. A timeout of zero is interpreted as an infinite timeout.
但是PlainSocketImpl(here,is SSLSocketImpl).getTimeout()返回的值是通过setSoTimeout()方法传过来的,那么还是一个很奇怪的方法。
SocketInputStream.socketRead0(FileDescriptor fd, byte b[], int off, int len, int timeout)
the timeout value is passed in the constructor of SocketInputStream:SocketInputStream(PlainSocketImpl impl) throws IOException {}
timeout = impl.getTimeout();