How could one convert the `try-with-resources` con...

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[JP]

How could one convert the try-with-resources construct in Java to Kotlin, regarding handling exceptions?

// Java
DataSource ds = createDataSource();
try (Connection connection = ds.getConnection()) {
    // ...
    // just throw exception for simulation
    throw new IllegalStateException()
    // ...
} catch (SQLException e) {
    e.printStackTrace()
}

I’ve tried to use the use function like this:

// Kotlin
val ds: DataSource = createDataSource()
try {
    dataSource.connection.use { connection ->
        // just throw exception for simulation
        throw IllegalStateException()
    }
} catch (e: SQLException) {
    e.printStackTrace()
}

But SQLException is not caught, instead, only IllegalStateException could be caught.
How could one catch a SQLException thrown from java.sql.Connection.getConnection() gracefully using Kotlin, while, if possible, utilizing the use function to close the connection?

[asad.awadia]

can you move the catch inside the use?

[JP]

No, it also wouldn’t work.

[louiscad]

I find it pretty normal that you get what you throw and not another exception. If you want to test SQLException, then throw a SQLException, not something else.

[jbnizet]

@JP to elaborate on Louis’s comment, your code works fine. Here’s a complete example testing the right exception:

import java.sql.SQLException

class Connection : AutoCloseable {
    override fun close() {
    }
}

class DataSource {
    val connection: Connection
        get() {
            throw SQLException("Ooops")
        }
}

fun createDataSource() = DataSource()

fun main() {
    val ds: DataSource = createDataSource()
    try {
        ds.connection.use { connection ->
            // just throw exception for simulation
            throw IllegalStateException()
        }
    } catch (e: SQLException) {
        println("Caught SQLException")
        e.printStackTrace()
    }
}

[JP]

Thank you for the comments. I think I now have a better understanding than before. @jbnizet Is it frequently done in practice then, to wrap try/catch block outside the use block, and also use another try/catch block inside the use block for example, in case of executing rollback before the AutoClosable resource is closed by the use block? Or is there a more concise way to handle it?