Play2.6 Java开发模式禁用调试视图，配置自定义错误页

Got it, let's fix this! Play 2.6's dev mode defaults to showing verbose debug pages, but we can override that with a custom ErrorHandler that works seamlessly in both dev and production environments. Here's a step-by-step solution tailored to your needs:

1. Create a Custom Error Handler Class #

First, we'll extend Play's DefaultHttpErrorHandler to override how errors are handled. This class will redirect 404s to your 404err.scala.html, general server errors to 500err.scala.html, and database connection errors to dbDownErr.scala.html.

Create a new Java class (e.g., CustomErrorHandler.java) in your application's package (replace com.yourapp with your actual package name):

import play.http.DefaultHttpErrorHandler;
import play.mvc.Http;
import play.mvc.Result;
import play.mvc.Results;
import javax.inject.Inject;
import javax.inject.Singleton;
import java.sql.SQLException;
import java.util.concurrent.CompletableFuture;
import java.util.concurrent.CompletionStage;

@Singleton
public class CustomErrorHandler extends DefaultHttpErrorHandler {

    @Inject
    public CustomErrorHandler(HttpErrorHandler.Context context) {
        super(context);
    }

    // Handle client-side errors like 404
    @Override
    protected CompletionStage<Result> onClientError(Http.RequestHeader request, int statusCode, String message) {
        if (statusCode == 404) {
            return CompletableFuture.completedFuture(
                Results.notFound(views.html.404err.render())
            );
        }
        // Fallback to default for other client errors if needed
        return super.onClientError(request, statusCode, message);
    }

    // Handle server-side errors including database issues
    @Override
    protected CompletionStage<Result> onServerError(Http.RequestHeader request, Throwable exception) {
        // Detect database connection errors (adjust the check based on your actual exception type)
        if (exception instanceof SQLException || (exception.getCause() != null && exception.getCause() instanceof SQLException)) {
            return CompletableFuture.completedFuture(
                Results.internalServerError(views.html.dbDownErr.render())
            );
        }
        // Catch-all for other 500 errors
        return CompletableFuture.completedFuture(
            Results.internalServerError(views.html.500err.render())
        );
    }
}

2. Register the Custom Error Handler #

Next, tell Play to use your custom handler instead of the default one. Open your conf/application.conf file and add this line:

play.http.errorHandler = "com.yourapp.CustomErrorHandler"

Make sure to replace com.yourapp with the actual package path where you saved your CustomErrorHandler class.

3. Verify Your Setup #

• Ensure your custom error views (404err.scala.html, 500err.scala.html, dbDownErr.scala.html) are located in the views directory of your Play project.
• Start (or restart) your application in dev mode. Now, when you trigger a 404 error, a general server error, or a database connection issue, you should see your custom pages instead of Play's debug views.

A quick note: Play's dev mode hot-reloading will pick up changes to your error handler or views automatically, so you don't need to restart the app every time you tweak things.

内容的提问来源于stack exchange，提问作者Kortas Aladinne