我正在尝试将新的Android Nearby Connections v2.0 API与 P2P_CLUSTER 连接策略一起使用 . 以下问题（两个设备都请求连接，但不要't successfully connect) seems to occur on a variety of devices running Android K-N. Sometimes the code gets a successful persistent connection... Sometimes it doesn' t .
在这种情况下，双方都是广告和发现，双方互相发现，双方都发送连接请求（但没有启动连接） . 使用特定的测试用例很难使这种情况可靠地发生，但它确实发生了 .
使用Android Monitor，我从一侧捕获了有关此方案的详细信息，并列出了下面的事件顺序 . 在这个特定的会话中，我正在监控的设备是一个非常便宜的KitKat手机，远程 endpoints 是三星Lollipop平板电脑（如果相关的话） .
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已发现远程节点，我们发出
requestConnection -
之后，Android Monitor立即显示此错误： ``
09-28 11:49:38.706 17321-17823/? E/NearbyConnections: In startClient(), UKEY2 failed with endpoint AqXW
java.io.IOException: bt socket closed, read return: -1
at android.bluetooth.BluetoothSocket.read(BluetoothSocket.java:647)
at android.bluetooth.BluetoothInputStream.read(BluetoothInputStream.java:96)
at java.io.InputStream.read(InputStream.java:162)
at java.io.BufferedInputStream.fillbuf(BufferedInputStream.java:149)
at java.io.BufferedInputStream.read(BufferedInputStream.java:295)
at libcore.io.Streams.readFully(Streams.java:81)
at java.io.DataInputStream.readInt(DataInputStream.java:103)
at xkj.c(:com.google.android.gms@11509230:1)
at xkg.run(:com.google.android.gms@11509230:8)
at mng.run(:com.google.android.gms@11509230:25)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
at mso.run(:com.google.android.gms@11509230)
at java.lang.Thread.run(Thread.java:818)
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之后，它立即使用
STATUS_ENDPOINT_IO_ERROR（8012）命中requestConnection的ResultCallback . -
接下来，因为
requestConnection返回错误，我们停止发现，等待3秒，然后再次开始发现 . -
我们重新启动发现后的下一条跟踪消息来自NearbyConnections： ``
09-28 11:49:46.333 17321-17412/? E/NearbyConnections: onIncomingConnection() for client 308946494 failed to initialize the connection with IkFxWFf_F-sAAAAAAAAAHHA_I2pIK25WaixTQEZSNHtVbmtub3duIFVzZXI
java.io.IOException: Failed to read ConnectionRequestFrame
at xjj.a(:com.google.android.gms@11509230:61)
at xlr.run(:com.google.android.gms@11509230:12)
at mng.run(:com.google.android.gms@11509230:25)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
at mso.run(:com.google.android.gms@11509230)
at java.lang.Thread.run(Thread.java:818)
Caused by: java.io.IOException: bt socket closed, read return: -1
at android.bluetooth.BluetoothSocket.read(BluetoothSocket.java:647)
at android.bluetooth.BluetoothInputStream.read(BluetoothInputStream.java:96)
at java.io.InputStream.read(InputStream.java:162)
at java.io.BufferedInputStream.fillbuf(BufferedInputStream.java:149)
at java.io.BufferedInputStream.read(BufferedInputStream.java:295)
at libcore.io.Streams.readFully(Streams.java:81)
at java.io.DataInputStream.readInt(DataInputStream.java:103)
at xkj.c(:com.google.android.gms@11509230:1)
at xjj.a(:com.google.android.gms@11509230:56)
at xlr.run(:com.google.android.gms@11509230:12)
at mng.run(:com.google.android.gms@11509230:25)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
at mso.run(:com.google.android.gms@11509230)
at java.lang.Thread.run(Thread.java:818)
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我'm guessing that the above error was triggered from a requestConnection from the other side? And if we hadn' t有这个错误，它会转到我的
onConnectionInitiated回调？ （只是为了澄清：它没有击中我的onConnectionInitiated回调 . ） -
接下来，我再次发现另一个节点，再次发现
requestConnection. -
在此之后，我立即看到来自NearbyConnections的以下（不同）错误消息： ``
09-28 11:51:14.639 17321-17412/? E/NearbyConnections: sendConnectionRequest() for client 308946494 failed to initialize the connection with endpoint AqXW
xjx: In connectImpl(), failed to connect to Bluetooth device 28:BE:03:0C:F1:5B for endpoint AqXW
at xlo.a(:com.google.android.gms@11509230:126)
at xjs.run(:com.google.android.gms@11509230:12)
at mng.run(:com.google.android.gms@11509230:25)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
at mso.run(:com.google.android.gms@11509230)
at java.lang.Thread.run(Thread.java:818)
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接下来，我们用
STATUS_BLUETOOTH_ERROR（8007）命中了requestConnection的ResultCallback -
在此之后，我看到了多次重复的设备connect then auto-disconnect . 他们从来没有得到过成功的持久连接，虽然我已经看到这种情况发生在一堆错误之后 .
1 回答
这是同时发生的连接冲突;如果您有2个设备同时相互连接，则在第二个设备在两个设备上触发onConnectionInititated（）之前，Nearby Connections将（随机）首先使设备的requestConnection（）之一失败 . 这就是你在第一个日志中看到“java.io.IOException：bt socket closed，read return：-1”的原因 .
如果不是STATUS_BLUETOOTH_ERROR失败，您应该看到两个设备成功连接 .