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CDI 2.0: Java SE support

Java SE support

The Java SE support in weld is now standardized, it is useful when you want to get CDI support out of Java EE application servers.
Given a simple CDI bean.
@Named
@ApplicationScoped
public class Greeter {

    public void say(String name) {
        System.out.println("Hi, " + name);
    }
}
You can start CDI SeContainer like this.
 SeContainerInitializer initializer = SeContainerInitializer.newInstance();
try (SeContainer container = initializer.initialize()) {
 assertTrue(container.isRunning());
 Set<Bean<?>> greeters = container.getBeanManager().getBeans("greeter");
 assertTrue(greeters.size() == 1);
}
There is a try-resources statement, SeContainer is a AutoClosable and can be closed automaticially at the end.
To bootstrap CDI container for Java SE, you have to add the following dependencies in project.
<dependency>
 <groupId>org.jboss.weld.se</groupId>
 <artifactId>weld-se-shaded</artifactId>
 <version>3.0.0.Final</version>
</dependency>
Weld also provides some simple APIs to bootstrap a CDI container.
Weld weld = new Weld();

try (WeldContainer container = weld.initialize()) {
 Greeter greeter = container.select(Greeter.class).get();
 assertTrue(greeter != null);
}
You can utilize Weld APIs to modify beans in the CDI container lifecycle.
@Test(expected = UnsatisfiedResolutionException.class)
public void bootWeldSeContainer() {
 Extension testExtension = ContainerLifecycleObserver.extensionBuilder()
  .add(afterBeanDiscovery((e) -> System.out.println("Bean discovery completed!")))
  .add(processAnnotatedType().notify((e) -> {
   if (e.getAnnotatedType().getJavaClass().getName().startsWith("com.hantsylab")) {
    e.veto();
   }
  }))
  .build();
 try (WeldContainer container = new Weld().addExtension(testExtension).initialize()) {
  Greeter greeter = container.select(Greeter.class).get();
  //assertTrue(greeter == null);
 }
}
In the above codes, it vetoes Greeter bean in processAnnotatedType phase, the later bean select operation will cause an exception UnsatisfiedResolutionException thrown.
Grab the source codes from my github account, and have a try.

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