Show non-500 Results for Exceptions

Application.java

import actions.*;

...

    @Transactional
    @ResultExceptionHandling
    public static Result list(int page, String sortBy, String order, String filter) {
        if (page == 2) throw new ResultException(ok("transaction rolled back"));
        return ok(
            list.render(
                Computer.page(page, 10, sortBy, order, filter),
                sortBy, order, filter
            )
        );
    }

...

ResultException.java

package actions;

import play.mvc.*;
import play.mvc.Http.*;

public class ResultException extends RuntimeException {
  private Result result;
  public ResultException(Result result) {
    this.result = result;
  }
  public Result getResult() {
    return result;
  }
}

ResultExceptionHandling.java

package actions;

import play.mvc.*;
import play.mvc.Http.*;

import java.util.*;
import java.lang.annotation.*;

@With(ResultExceptionHandlingAction.class)
@Target({ElementType.TYPE, ElementType.METHOD})
@Retention(RetentionPolicy.RUNTIME)
public @interface ResultExceptionHandling {
    String value() default "default";
    boolean readOnly() default false;
}

ResultExceptionHandlingAction.java

package actions;

import play.libs.F;
import play.mvc.*;
import play.mvc.Http.*;

public class ResultExceptionHandlingAction extends Action<ResultExceptionHandling> {
    
    public Result call(final Context ctx) throws Throwable {
      try {
        return delegate.call(ctx);
      } catch (ResultException resultException) {
        return resultException.getResult();
      }
    }

}