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Spark Debug Screen

Error pages for the Spark Java micro-framework.

image

Usage:

To utilize:

package spark.debug;

import static spark.Spark.get;
import static spark.Spark.port;
import static spark.debug.DebugScreen.enableDebugScreen;

public class DebugScreenExample {
    public static void main(String[] args) {

        get("*", (req, res) -> {
            throw new Exception("Exceptions everywhere!");
        });
        
        enableDebugScreen(); //just add this to your project to enable the debug screen
        
    }
}

Maven:

<dependency>
    <groupId>com.sparkjava</groupId>
    <artifactId>spark-debug-tools</artifactId>
    <version>0.5</version>
</dependency>

Advanced Usage:

To add additional tables:


// Subclass the handler:
class MyDebugScreen extends DebugScreen {
  @Override
  protected void installTables(LinkedHashMap<String, Map<String, ? extends Object>> tables, Request request, Exception exception) {
    super.installTables(tables, request, exception);
    Map<String, Object> myTable = new LinkedHashMap<>();
    tables.put("My Table", myTable);
    myTable.put("Key", "Value");
  }
}

// When installing the exception handler, install yours instead:
Spark.exception(Exception.class, new MyDebugScreen());

To change the search path for locating Java source files:

By default DebugScreen looks within the folders src/main/java and src/test/java in the current working directory (if they exist). If you have changed the working directory, obviously this approach will not work. You can specify different search directories:

Spark.exception(Exception.class, new DebugScreen(
    ImmutableList.of(new FileSearchSourceLocator(new File("/path/to/source/code")))
));

You can specify multiple locators in the list (later ones are used as fallbacks if earlier ones cannot find a file). If this is still not specific enough for you, you can implement your own SourceLocator to find the files and provide that to the handler.

Notes:

Credits:

By mschurr. Based on filp/whoops.