我在项目中使用Spring Integration，我的上下文中有一个int-ftp:inbound-channel-adapter，如下所示：
<int-ftp:inbound-channel-adapter id="test-inbound-channel-adapter"
channel="tmp-channel"
session-factory="ftp-Session"
auto-create-local-directory="true"
delete-remote-files="true"
auto-startup="${ftp.active}"
filename-regex="my regex ...."
remote-directory="${ftp.input.path}"
remote-file-separator="/"
local-filename-generator-expression="@fileNameGenerator.generateNameBy('test',#this)"
temporary-file-suffix=".writing"
local-directory="${backupRootPath}/test/tmp//">
<int:poller fixed-rate="10000"/>
</int-ftp:inbound-channel-adapter>
它可以正常工作，但几分钟后就不能与ftp服务器一起工作了，系统应该重新启动，错误日志如下：
2016-07-31 17:11:08.381 ERROR 2980 --- [sk-scheduler-10] o.s.integration.handler.LoggingHandler : org.springframework.messaging.MessagingException: Problem occurred while synchronizing remote to local directory; nested exception is org.springframework.messaging.MessagingException: Failure occurred while copying from remote to local directory; nested exception is java.net.SocketTimeoutException: Read timed out
at org.springframework.integration.file.remote.synchronizer.AbstractInboundFileSynchronizer.synchronizeToLocalDirectory(AbstractInboundFileSynchronizer.java:266)
at org.springframework.integration.file.remote.synchronizer.AbstractInboundFileSynchronizingMessageSource.doReceive(AbstractInboundFileSynchronizingMessageSource.java:193)
at org.springframework.integration.file.remote.synchronizer.AbstractInboundFileSynchronizingMessageSource.doReceive(AbstractInboundFileSynchronizingMessageSource.java:59)
at org.springframework.integration.endpoint.AbstractMessageSource.receive(AbstractMessageSource.java:134)
at org.springframework.integration.endpoint.SourcePollingChannelAdapter.receiveMessage(SourcePollingChannelAdapter.java:175)
at org.springframework.integration.endpoint.AbstractPollingEndpoint.doPoll(AbstractPollingEndpoint.java:224)
at org.springframework.integration.endpoint.AbstractPollingEndpoint.access$000(AbstractPollingEndpoint.java:57)
at org.springframework.integration.endpoint.AbstractPollingEndpoint$1.call(AbstractPollingEndpoint.java:176)
at org.springframework.integration.endpoint.AbstractPollingEndpoint$1.call(AbstractPollingEndpoint.java:173)
at org.springframework.integration.endpoint.AbstractPollingEndpoint$Poller$1.run(AbstractPollingEndpoint.java:330)
at org.springframework.integration.util.ErrorHandlingTaskExecutor$1.run(ErrorHandlingTaskExecutor.java:55)
at org.springframework.core.task.SyncTaskExecutor.execute(SyncTaskExecutor.java:50)
at org.springframework.integration.util.ErrorHandlingTaskExecutor.execute(ErrorHandlingTaskExecutor.java:51)
at org.springframework.integration.endpoint.AbstractPollingEndpoint$Poller.run(AbstractPollingEndpoint.java:324)
at org.springframework.scheduling.support.DelegatingErrorHandlingRunnable.run(DelegatingErrorHandlingRunnable.java:54)
at org.springframework.scheduling.concurrent.ReschedulingRunnable.run(ReschedulingRunnable.java:81)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(ScheduledThreadPoolExecutor.java:180)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:293)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
Caused by: org.springframework.messaging.MessagingException: Failure occurred while copying from remote to local directory; nested exception is java.net.SocketTimeoutException: Read timed out
at org.springframework.integration.file.remote.synchronizer.AbstractInboundFileSynchronizer.copyFileToLocalDirectory(AbstractInboundFileSynchronizer.java:295)
at org.springframework.integration.file.remote.synchronizer.AbstractInboundFileSynchronizer$1.doInSession(AbstractInboundFileSynchronizer.java:234)
at org.springframework.integration.file.remote.synchronizer.AbstractInboundFileSynchronizer$1.doInSession(AbstractInboundFileSynchronizer.java:223)
at org.springframework.integration.file.remote.RemoteFileTemplate.execute(RemoteFileTemplate.java:410)
at org.springframework.integration.file.remote.synchronizer.AbstractInboundFileSynchronizer.synchronizeToLocalDirectory(AbstractInboundFileSynchronizer.java:223)
... 22 more
Caused by: java.net.SocketTimeoutException: Read timed out
at java.net.SocketInputStream.socketRead0(Native Method)
at java.net.SocketInputStream.read(SocketInputStream.java:150)
at java.net.SocketInputStream.read(SocketInputStream.java:121)
at sun.nio.cs.StreamDecoder.readBytes(StreamDecoder.java:284)
at sun.nio.cs.StreamDecoder.implRead(StreamDecoder.java:326)
at sun.nio.cs.StreamDecoder.read(StreamDecoder.java:178)
at java.io.InputStreamReader.read(InputStreamReader.java:184)
at java.io.BufferedReader.fill(BufferedReader.java:161)
at java.io.BufferedReader.read(BufferedReader.java:182)
at org.apache.commons.net.io.CRLFLineReader.readLine(CRLFLineReader.java:58)
at org.apache.commons.net.ftp.FTP.__getReply(FTP.java:314)
at org.apache.commons.net.ftp.FTP.__getReply(FTP.java:294)
at org.apache.commons.net.ftp.FTP.sendCommand(FTP.java:483)
at org.apache.commons.net.ftp.FTPClient._openDataConnection_(FTPClient.java:821)
at org.apache.commons.net.ftp.FTPClient._retrieveFile(FTPClient.java:1854)
at org.apache.commons.net.ftp.FTPClient.retrieveFile(FTPClient.java:1845)
at org.springframework.integration.ftp.session.FtpSession.read(FtpSession.java:81)
at org.springframework.integration.file.remote.synchronizer.AbstractInboundFileSynchronizer.copyFileToLocalDirectory(AbstractInboundFileSynchronizer.java:288)
... 26 more
如何修复？
提前感谢
尝试自定义DefaultFtpSessionFactory。例如客户端模式：
/**
* ACTIVE_LOCAL_DATA_CONNECTION_MODE = 0 <br>
* A constant indicating the FTP session is expecting all transfers
* to occur between the client (local) and server and that the server
* should connect to the client's data port to initiate a data transfer.
* This is the default data connection mode when and FTPClient instance
* is created.
* PASSIVE_LOCAL_DATA_CONNECTION_MODE = 2 <br>
* A constant indicating the FTP session is expecting all transfers
* to occur between the client (local) and server and that the server
* is in passive mode, requiring the client to connect to the
* server's data port to initiate a transfer.
*
* @param clientMode The client mode.
*/
public void setClientMode(int clientMode) {
关于超时还有其他选项：
/**
* Set the connect timeout for the socket.
* @param connectTimeout the timeout
*/
public void setConnectTimeout(int connectTimeout) {
this.connectTimeout = connectTimeout;
}
/**
* Set the (socket option) timeout on the command socket.
* @param defaultTimeout the timeout.
*/
public void setDefaultTimeout(int defaultTimeout) {
this.defaultTimeout = defaultTimeout;
}
/**
* Set the (socket option) timeout on the data connection.
* @param dataTimeout the timeout.
*/
public void setDataTimeout(int dataTimeout) {
this.dataTimeout = dataTimeout;
}
当然，最好咨询一下你的FTP服务器，看看它为什么不喜欢你的连接并放弃它们。