MySQLNonTransientConnectionException:无法创建与数据库服务器的连接 [英] MySQLNonTransientConnectionException: Could not create connection to database server

问题描述

我正在处理一个奇怪的问题，即使用JDBC连接到Amazon RDS上的MySQL数据库.我在同一网络上有两个运行相同代码的不同Android手机.一个连接没有任何问题.另一个是给我以下异常:

I am dealing with a strange problem connecting to my MySQL database on Amazon RDS using JDBC. I have two different Android phones on the same network running the same code. One connects without any problems. The other is giving me the following exception:

com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection to database server.
    at java.lang.reflect.Constructor.constructNative(Native Method)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:417)
    at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
    at com.mysql.jdbc.Util.getInstance(Util.java:386)
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1014)
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:988)
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:974)
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:919)
    at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2547)
    at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2283)
    at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:822)
    at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47)
    at java.lang.reflect.Constructor.constructNative(Native Method)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:417)
    at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
    at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:404)
    at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:317)
    at java.sql.DriverManager.getConnection(DriverManager.java:175)
    at java.sql.DriverManager.getConnection(DriverManager.java:209)
    at edu.ucsb.cs.epsilon.ucsb360.DatabaseManager.Connect(DatabaseManager.java:32)
    at edu.ucsb.cs.epsilon.ucsb360.Global.applicationResumed(Global.java:31)
    at edu.ucsb.cs.epsilon.ucsb360.MainActivity.onResume(MainActivity.java:54)
    at android.app.Instrumentation.callActivityOnResume(Instrumentation.java:1236)
    at android.app.Activity.performResume(Activity.java:4625)
    at android.app.ActivityThread.performResumeActivity(ActivityThread.java:2834)
    at android.app.ActivityThread.handleResumeActivity(ActivityThread.java:2889)
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1303)
    at android.os.Handler.dispatchMessage(Handler.java:99)
    at android.os.Looper.loop(Looper.java:156)
    at android.app.ActivityThread.main(ActivityThread.java:5045)
    at java.lang.reflect.Method.invokeNative(Native Method)
    at java.lang.reflect.Method.invoke(Method.java:511)
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
    at dalvik.system.NativeStart.main(Native Method)
Caused by: android.os.NetworkOnMainThreadException
    at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1190)
    at java.net.InetAddress.lookupHostByName(InetAddress.java:394)
    at java.net.InetAddress.getAllByNameImpl(InetAddress.java:245)
    at java.net.InetAddress.getAllByName(InetAddress.java:220)
    at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:249)
    at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:305)
    at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2461)
    at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2498)

数据库仅显示1个活动连接，所以我知道不是因为打开的连接过多.我曾尝试重新启动服务器，但没有帮助.我正在使用MySQL JDBC Connector/J版本5.1.23.运行正常的手机正在运行Android 2.3.5版，而运行不正常的手机正在运行Android 4.0.4版.有人对可能出什么问题有任何想法吗?

The database only shows 1 active connection, so I know it is not because of too many open connections. I have tried rebooting the server, but it didn't help. I am using the MySQL JDBC Connector/J version 5.1.23. The phone that works is running Android version 2.3.5 and the one that doesn't work is running Android version 4.0.4. Does anyone have any ideas as to what might be wrong?

谢谢！

推荐答案

Caused by: android.os.NetworkOnMainThreadException

您不能在主线程上进行网络IO.将其移至AsyncTask或线程.

You can't do network IO on the main thread. Move it to an AsyncTask or thread.

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