Efxclipse/Runtime/Recipes

This page holds best practice recipes when writing JavaFX application using e(fx)clipse

Logging

e(fx)clipse has its own logging facade org.eclipse.fx.core.log.Logger which allows to plug-in different log frameworks.

Currently available are:

• java.util.Logging (default)
• log4j by adding org.eclipse.fx.core.log4j bundle to your OSGi-Runtime

Usage

There are different ways to use get a logger.

LoggerCreator

If you are running on OSGi you can add the org.eclipse.fx.osgi.util bundle which provides access to the LoggerCreator factory class

import org.eclipse.fx.core.log.Logger;
import org.eclipse.fx.osgi.util.LoggerCreator;
 
public class MyClass {
  private static Logger LOGGER = LoggerCreator.createLogger(MyClass.class);
 
  // ....
}

LoggerFactory Service

The different logger bundles contribute their LoggerFactory implementation into the OSGi-Registry. In case you are e.g. contributing a service via DS you can get simple add a service reference and you'll get the LoggerFactory with the highest rank injected.

import org.eclipse.fx.core.log.LoggerFactory;
import org.eclipse.fx.core.log.Logger;
 
public class MyServiceImpl implements MyService {
  private Logger logger;
 
  public void setLoggerFactory(LoggerFactory factory) {
    this.logger = factory.createLogger(MyService.class.getName());
  }
 
  public void unsetLoggerFactory(LoggerFactory factory) {
 
  }
}

<?xml version="1.0" encoding="UTF-8"?>
<scr:component xmlns:scr="http://www.osgi.org/xmlns/scr/v1.1.0" name="myservice">
   <implementation class="impl.MyServiceImpl"/>
   <service>
      <provide interface="service.MyService"/>
   </service>
   <reference bind="setLoggerFactory" cardinality="1..1" interface="org.eclipse.fx.core.log.LoggerFactory" name="LoggerFactory" policy="static" unbind="unsetLoggerFactory"/>
</scr:component>

Eclipse DI & @Log annotation

If you make use of Eclipse DI in your code you can get a Logger instance injected with:

import org.eclipse.fx.core.log.Log;
import org.eclipse.fx.core.log.Logger;
import javax.inject.Inject;
 
public class MyDIComponent {
 
  @Inject
  @Log
  Logger logger;
}

Google Guice & @Log annotation

If you use Guice as the DI container you use the org.eclipse.fx.core.guice bundle to get a Logger injected in your component with:

import org.eclipse.fx.core.log.Log;
import org.eclipse.fx.core.log.Logger;
import javax.inject.Inject;
 
public class MyDIComponent {
 
  @Log
  Logger logger;
}

if you have configured your Guice-Module with:

import com.google.inject.Module;
import com.google.inject.Binder;
import org.eclipse.fx.core.log.LoggerFactory;
import org.eclipse.fx.core.log4j.Log4JLoggerFactory;
import org.eclipse.fx.core.guice.FXLoggerListener;
 
public class MyModule implements Module {
  public void configure(Binder binder) {
    binder.bind(LoggerFactory.class).toProvider(Log4JLoggerFactory.class); // or JUtilLoggerFactory
    binder.bindListener(Matchers.any(), new FXLoggerListener());
  }
}

Instead of directly binding to a logger factory you can delegate to the OSGi-Service registry by using OSGiLoggerFactoryProvider:

import com.google.inject.Module;
import com.google.inject.Binder;
import org.eclipse.fx.core.log.LoggerFactory;
import org.eclipse.fx.core.guice.FXLoggerListener;
import org.eclipse.fx.core.guice.OSGiLoggerFactoryProvider;
 
public class MyModule implements Module {
  public void configure(Binder binder) {
    binder.bind(LoggerFactory.class).toProvider(OSGiLoggerFactoryProvider.class);
    binder.bindListener(Matchers.any(), new FXLoggerListener());
  }
}

Extending

Like outlined above there are 2 logger implementations available from the e(fx)clipse p2 repository. If you want to use a different logging framework you are able to plug-in your own by implementing LoggerFactory and contributing it to the OSGi-Service-Registry.

import javax.inject.Provider;
import org.eclipse.fx.core.log.LoggerFactory;
import org.eclipse.fx.core.log.Logger;
 
public class MyLoggerFactory implements LoggerFactory, Provider<LoggerFactory> {
  @Override
  public LoggerFactory get() {
    return this;
  }
 
  @Override
  public Logger createLogger(String name) {
    return new LoggerImpl(name);
  }
 
  static class LoggerImpl implements Logger {
    private String name;
 
    public LoggerImpl(String name) {
      this.name = name;
    }
 
    // ....
  }
}

You contribute it to the OSGi-Service registry e.g. by using DS. You should give the service a higher ranking than 1 (which is the ranking of the log4j service) to ensure it is picked when a logger is requested.

<?xml version="1.0" encoding="UTF-8"?>
<scr:component xmlns:scr="http://www.osgi.org/xmlns/scr/v1.1.0" name="my.logger.framework.factory">
   <implementation class="my.logger.framework.MyLoggerFactory"/>
   <property name="service.ranking" type="Integer" value="2"/>
   <service>
      <provide interface="org.eclipse.fx.core.log.LoggerFactory"/>
   </service>
</scr:component>

Eclipse DI

Publishing to the IEclipseContext

The IEclipseContext is the central component of the Eclipse DI container. Retrieving values from it is as easy as writing @Inject in your java class and the DI container will fill it with a value and keep it up-to-date if you used field or method injection.

The opposite - publishing a value into the context - is not as easy because your java component will get a dependency on the DI-Container because it needs to access the IEclipseContext directly. e(fx)clipse provides you the possibility to get around this architectual problem by defining an annotation named @ContextValue which marks a slot in IEclipseContext instance which can be used to observe the value and modified.

import org.eclipse.fx.core.di.ContextBoundValue;
import org.eclipse.fx.core.di.ContextValue;
import javax.inject.Inject;
 
public static class SimpleInject {
  @Inject
  @ContextValue(contextKey="user")
  public ContextBoundValue<String> value;
 
  private void updateValue() {
    value.publish("tomschindl");
  }
}

To make use of this your bundle needs to have a dependency on org.eclipse.fx.core.di and your runtime has to include org.eclipse.fx.core.di.context.