| = CDI Field Producer |
| :index-group: CDI |
| :jbake-type: page |
| :jbake-status: published |
| |
| Este exemplo mostra o uso da anotação `@Produces`. `@Produces` é um mecanismo do CDI que permite definir uma fonte para injeção. Este exemplo mostra uma das duas formas de declarar um producer. Ao invés de um produces method (veja no exemplo CDI-produces-disposes), um producer field pode ser usado. Um producer field pode ser usado ao invés de um simples método getter. Isso pode ser usado para injetar recursos como, contexto de persistência. Uma ressalva para o uso de produces fields sobre produces method é que um método `@Disposes` não pode ser usado junto de um `@Produces` field. |
| |
| Para o proposito deste exemplo, `type` é hard-coded em um valor especifico. Uma implementação de Logger deve conter uma lista de LogHandlers. Nós devemos ter três implementações da interface LogHandler. |
| |
| * Uma DatabaseHandler |
| * Uma FileHandler |
| * Uma ConsoleHandler |
| |
| A implementação DatabaseHandler aparentemente gravaria os logs em um banco de dados. O FileHandler gravaria os mesmos logs em um arquivo. E o ConsoleHandler apenas imprimiria os logs no console. Este exemplo é apenas uma ilustração de como os conceitos dentro do CDI funcionam e não tem a intenção de fornecer uma implementação/design de estrutura de log. |
| |
| == ConsoleHandler |
| |
| [source,java] |
| ---- |
| package org.superbiz.cdi.produces.field; |
| |
| public class ConsoleHandler implements LogHandler { |
| |
| private String name; |
| |
| public ConsoleHandler(String name) { |
| this.name = name; |
| } |
| |
| @Override |
| public String getName() { |
| return name; |
| } |
| |
| @Override |
| public void writeLog(String s) { |
| System.out.printf("##### Handler: %s, Writing to the console!\n", getName()); |
| } |
| } |
| ---- |
| |
| == DatabaseHandler |
| |
| [source,java] |
| ---- |
| package org.superbiz.cdi.produces.field; |
| |
| public class DatabaseHandler implements LogHandler { |
| |
| private String name; |
| |
| public DatabaseHandler(String name) { |
| this.name = name; |
| } |
| |
| @Override |
| public String getName() { |
| return name; |
| } |
| |
| @Override |
| public void writeLog(String s) { |
| System.out.printf("##### Handler: %s, Writing to the database!\n", getName()); |
| // Use connection to write log to database |
| } |
| } |
| ---- |
| |
| == FileHandler |
| |
| [source,java] |
| ---- |
| package org.superbiz.cdi.produces.field; |
| |
| public class FileHandler implements LogHandler { |
| |
| private String name; |
| |
| public FileHandler(String name) { |
| this.name = name; |
| } |
| |
| @Override |
| public String getName() { |
| return name; |
| } |
| |
| @Override |
| public void writeLog(String s) { |
| System.out.printf("##### Handler: %s, Writing to the file!\n", getName()); |
| // Escreve para o arquivo de log |
| } |
| } |
| ---- |
| |
| == LogFactory |
| |
| [source,java] |
| ---- |
| package org.superbiz.cdi.produces.field; |
| |
| import javax.enterprise.inject.Produces; |
| |
| public class LogFactory { |
| |
| private int type = 2; |
| |
| @Produces |
| LogHandler handler; |
| |
| public LogFactory(){ |
| handler = getLogHandler(); |
| } |
| |
| public LogHandler getLogHandler() { |
| switch (type) { |
| case 1: |
| return new FileHandler("@Produces created FileHandler!"); |
| case 2: |
| return new DatabaseHandler("@Produces created DatabaseHandler!"); |
| case 3: |
| default: |
| return new ConsoleHandler("@Produces created ConsoleHandler!"); |
| } |
| |
| } |
| } |
| ---- |
| |
| == Logger |
| |
| [source,java] |
| ---- |
| package org.superbiz.cdi.produces.field; |
| |
| public interface Logger { |
| |
| public void log(String s); |
| |
| public LogHandler getHandler(); |
| } |
| ---- |
| |
| == LoggerImpl |
| |
| [source,java] |
| ---- |
| package org.superbiz.cdi.produces.field; |
| |
| import javax.inject.Inject; |
| import javax.inject.Named; |
| |
| @Named("logger") |
| public class LoggerImpl implements Logger { |
| |
| @Inject |
| private LogHandler handler; |
| |
| @Override |
| public void log(String s) { |
| getHandler().writeLog(s); |
| } |
| |
| public LogHandler getHandler() { |
| return handler; |
| } |
| } |
| ---- |
| |
| == LogHandler |
| |
| [source,java] |
| ---- |
| package org.superbiz.cdi.produces.field; |
| |
| public interface LogHandler { |
| |
| public String getName(); |
| |
| public void writeLog(String s); |
| } |
| ---- |
| |
| == beans.xml |
| |
| [source,xml] |
| ---- |
| <beans xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" |
| xsi:schemaLocation="http://java.sun.com/xml/ns/javaee |
| http://java.sun.com/xml/ns/javaee/beans_1_0.xsd"> |
| |
| </beans> |
| ---- |
| |
| == LoggerTest |
| |
| [source,java] |
| ---- |
| package org.superbiz.cdi.produces.field; |
| |
| import org.junit.After; |
| import org.junit.Before; |
| import org.junit.Test; |
| |
| import javax.ejb.embeddable.EJBContainer; |
| import javax.inject.Inject; |
| import javax.naming.Context; |
| |
| import static junit.framework.Assert.assertNotNull; |
| import static org.junit.Assert.assertFalse; |
| import static org.junit.Assert.assertTrue; |
| |
| public class LoggerTest { |
| |
| @Inject |
| Logger logger; |
| |
| private Context ctxt; |
| |
| @Before |
| public void setUp() { |
| try { |
| ctxt = EJBContainer.createEJBContainer().getContext(); |
| ctxt.bind("inject", this); |
| } catch (Exception e) { |
| e.printStackTrace(); |
| } |
| } |
| |
| @After |
| public void cleanUp() { |
| try { |
| ctxt.unbind("inject"); |
| ctxt.close(); |
| } catch (Exception e) { |
| e.printStackTrace(); |
| } |
| } |
| |
| @Test |
| public void testLogHandler() { |
| assertNotNull(logger); |
| assertFalse("Handler should not be a ConsoleHandler", logger.getHandler() instanceof ConsoleHandler); |
| assertFalse("Handler should not be a FileHandler", logger.getHandler() instanceof FileHandler); |
| assertTrue("Handler should be a DatabaseHandler", logger.getHandler() instanceof DatabaseHandler); |
| logger.log("##### Testing write\n"); |
| logger = null; |
| } |
| |
| } |
| ---- |
| |
| = Executando |
| |
| [source,console] |
| ---- |
| ------------------------------------------------------- |
| T E S T S |
| ------------------------------------------------------- |
| Running org.superbiz.cdi.produces.field.LoggerTest |
| INFO - ******************************************************************************** |
| INFO - OpenEJB http://tomee.apache.org/ |
| INFO - Startup: Thu May 10 01:28:19 CDT 2012 |
| INFO - Copyright 1999-2012 (C) Apache OpenEJB Project, All Rights Reserved. |
| INFO - Version: 7.0.0-SNAPSHOT |
| INFO - Build date: 20120510 |
| INFO - Build time: 04:06 |
| INFO - ******************************************************************************** |
| INFO - openejb.home = /home/daniel/projects/openejb/source/openejb/examples/cdi-produces-field |
| INFO - openejb.base = /home/daniel/projects/openejb/source/openejb/examples/cdi-produces-field |
| INFO - Created new singletonService org.apache.openejb.cdi.ThreadSingletonServiceImpl@a81b1fb |
| INFO - succeeded in installing singleton service |
| INFO - Using 'javax.ejb.embeddable.EJBContainer=true' |
| INFO - Cannot find the configuration file [conf/openejb.xml]. Will attempt to create one for the beans deployed. |
| INFO - Configuring Service(id=Default Security Service, type=SecurityService, provider-id=Default Security Service) |
| INFO - Configuring Service(id=Default Transaction Manager, type=TransactionManager, provider-id=Default Transaction Manager) |
| INFO - Creating TransactionManager(id=Default Transaction Manager) |
| INFO - Creating SecurityService(id=Default Security Service) |
| INFO - Inspecting classpath for applications: 26 urls. Consider adjusting your exclude/include. Current settings: openejb.deployments.classpath.exclude='', openejb.deployments.classpath.include='.*' |
| INFO - Searched 26 classpath urls in 2015 milliseconds. Average 77 milliseconds per url. |
| INFO - Beginning load: /home/daniel/projects/openejb/source/openejb/examples/cdi-produces-field/target/classes |
| INFO - Configuring enterprise application: /home/daniel/projects/openejb/source/openejb/examples/cdi-produces-field |
| INFO - Auto-deploying ejb cdi-produces-field.Comp: EjbDeployment(deployment-id=cdi-produces-field.Comp) |
| INFO - Configuring Service(id=Default Managed Container, type=Container, provider-id=Default Managed Container) |
| INFO - Auto-creating a container for bean cdi-produces-field.Comp: Container(type=MANAGED, id=Default Managed Container) |
| INFO - Creating Container(id=Default Managed Container) |
| INFO - Using directory /tmp for stateful session passivation |
| INFO - Enterprise application "/home/daniel/projects/openejb/source/openejb/examples/cdi-produces-field" loaded. |
| INFO - Assembling app: /home/daniel/projects/openejb/source/openejb/examples/cdi-produces-field |
| INFO - ignoreXmlConfiguration == true |
| INFO - ignoreXmlConfiguration == true |
| INFO - existing thread singleton service in SystemInstance() org.apache.openejb.cdi.ThreadSingletonServiceImpl@a81b1fb |
| INFO - OpenWebBeans Container is starting... |
| INFO - Adding OpenWebBeansPlugin : [CdiPlugin] |
| INFO - All injection points were validated successfully. |
| INFO - OpenWebBeans Container has started, it took [69] ms. |
| INFO - Deployed Application(path=/home/daniel/projects/openejb/source/openejb/examples/cdi-produces-field) |
| ##### Handler: @Produces created DatabaseHandler!, Writing to the database! |
| INFO - Undeploying app: /home/daniel/projects/openejb/source/openejb/examples/cdi-produces-field |
| Tests run: 1, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 3.79 sec |
| |
| Results : |
| |
| Tests run: 1, Failures: 0, Errors: 0, Skipped: 0 |
| ---- |