发生了一些不寻常的事情导致驱动程序失败。 Heroku postgresql 数据库

Question

I have created a heroku posgresql database and I am trying to connect my Android app to this database. I am using Android Studio for making the Android app. I have used the following code for creating the connection:

try {
    Class.forName("org.postgresql.Driver");
    Connection db = DriverManager.getConnection(dbUrl);
}
catch(Exception e){
    //handles exception
}

When I execute this code I get the following error: Something unusual has occurred tot cause the driver to fail. Please report this exception.

This is the driver I use: posgresql-42.2.12

The heroku database has version 12.2

Android studio has java version 1.8

I am not sure if the driver is in the classpath and I am not sure how to check this. I added the driver to the project this way: app > New > Module > Import.JAR/.AAR Package (here I selected the driver).

To check if the Driver is registered in DriverManager I used this code:

Enumeration<Driver> drivers = DriverManager.getDrivers();
drivers.nextElement().getClass().getName();

This gives: org.postgresql.Driver

To check if the Driver understandes the URL I used this code:

DriverManager.getDriver(dbUrl).getClass().getName();

This also gives org.posgresql.Driver so I think the Driver is registered to the DriverManager and should be able to connect to the database using the URL. I just really don't know why I keep getting an error when I try to connect with the database.

So why does the error occur and how can I resolve the issue?

Answer 1

My first guess would be a malformed connection string. Are you using a proper JDBC URL (ie it starts with jdbc: ) for dbUrl ? Also make sure you include sslmode=require .

In addition, please be aware that the database URL is managed by Heroku and will change under certain circumstances. You can read more about using Heroku Postgres from outside of Heroku in this DevCenter article .