Android file upload an inexplicable pit

The android phone is connected to the computer. 50 words are omitted
before

connection.getOutputStream()

ran to this sentence, nothing went through, there was no error, until the connection timed out. Check that the web server is started normally, and the android configuration is normal, even if adb -s T3Q6T16115007892 shell Input keyevent 82 The phone can pop up a dialog box.

After hard toss, suddenly the computer pops up a dialog, whether to allow java ... to access the network, click OK.
The problem is solved, this is too pit, how can the firewall, how can it be ...