Android Question JdbcSQL app works in debug but not in release

[atiaust]

Hi All,

My B4A app uses JdbcSQL to talk to a MySQL database on my local RPI server and performs flawlessly in debug mode but crashes in release mode.

Spoiler: Error message

*** Service (starter) Create ***
** Service (starter) Start **
** Activity (main) Create, isFirst = true **
main$ResumableSub_Activity_Createresume (java line: 401)
com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection to database server.
at java.lang.reflect.Constructor.newInstance0(Native Method)
at java.lang.reflect.Constructor.newInstance(Constructor.java:430)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:425)
at com.mysql.jdbc.Util.getInstance(Util.java:408)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:919)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:898)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:887)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:861)
at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2266)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2015)
at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:768)
at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47)
at java.lang.reflect.Constructor.newInstance0(Native Method)
at java.lang.reflect.Constructor.newInstance(Constructor.java:430)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:425)
at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:385)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:323)
at java.sql.DriverManager.getConnection(DriverManager.java:569)
at java.sql.DriverManager.getConnection(DriverManager.java:219)
at anywheresoftware.b4j.objects.SQL.Initialize2(SQL.java:56)
at JHS.ZbarBarcodeScanner.main$ResumableSub_Activity_Create.resume(main.java:401)
at JHS.ZbarBarcodeScanner.main._activity_create(main.java:375)
at java.lang.reflect.Method.invoke(Native Method)
at anywheresoftware.b4a.BA.raiseEvent2(BA.java:213)

Can anyone provide any ideas.

Thanks

 

[Erel]

Try this: Workaround the NetworkOnMainThread exception
Maybe this is the real error and it is caught internally and a different error shows.

 

[atiaust]

Thanks Erel,

This has allowed me to run the app in release mode.

For my education, what causes this?

 

[Erel]

One of the differences between debug and release is that the NetworkOnMainThread check is disabled in debug mode.
So without thinking too much I recommended to try it with this check disabled.

Truth is that you should switch to SQL.InitializeAsync as you don't want to do any network stuff on the main thread.