在java中捕获memcache异常

Question

I am using spymemcached-2.8.4.jar and jdk.1.7.

Here is my code

try {

     MemcachedClient client = new MemcachedClient(...);

     client.set('name', 1000, 'some_name');

}catch(Exception ex){
     System.out.println("Exception occurred");
     System.out.println(ex.getMessage());
     ex.printStackTrace();

     logExceptionInDB(ex);
}

In my scansion, my memcached machine is not running, so it is printing the following exception in console,

java.net.ConnectException: Connection refused
    at sun.nio.ch.SocketChannelImpl.checkConnect(Native Method)
    at sun.nio.ch.SocketChannelImpl.finishConnect(SocketChannelImpl.java:735)
    at net.spy.memcached.MemcachedConnection.handleIO(MemcachedConnection.java:369)
    at net.spy.memcached.MemcachedConnection.handleIO(MemcachedConnection.java:242)
    at net.spy.memcached.MemcachedConnection.run(MemcachedConnection.java:836)

But I want to catch this excepting to write it in database. How to catch this exception?

Answer 1

You can't catch the exception mentioned in the post, as it was already catch by spymemcached itself, you can only see the log, the related code in MemcachedConnection.java is :

catch (ConnectException var5) {
            this.getLogger().info("Reconnecting due to failure to connect to %s", new Object[]{node, var5});
            this.queueReconnect(node);
        }

It will try to reconnect afterwards, so make sure your configuration is right.
Actually, you can catch exception produced by set method:

    OperationFuture<Boolean> future = client.set("name", 1000, "some_name");
    Boolean result = future.get(50, TimeUnit.MILLISECONDS);

Assume that your timeout time for one operation is 50 milliseconds, you will get CheckedOperationTimeoutException after the time elapsed.