| :index-group: Environment Entries |
| :jbake-type: page |
| :jbake-status: status=published |
| = Using EnvEntries |
| |
| The `@Resource` annotation can be used to inject several things |
| including DataSources, Topics, Queues, etc. Most of these are container |
| supplied objects. |
| |
| It is possible, however, to supply your own values to be injected via an |
| `<env-entry>` in your `ejb-jar.xml` or `web.xml` deployment descriptor. |
| Java EE 6 supported `<env-entry>` types are limited to the following: |
| |
| * java.lang.String |
| * java.lang.Integer |
| * java.lang.Short |
| * java.lang.Float |
| * java.lang.Double |
| * java.lang.Byte |
| * java.lang.Character |
| * java.lang.Boolean |
| * java.lang.Class |
| * java.lang.Enum (any enum) |
| |
| See also the link:../custom-injection[Custom Injection] example for a |
| TomEE and OpenEJB feature that will let you use more than just the above |
| types as well as declare `<env-entry>` items with a plain properties |
| file. |
| |
| == Using @Resource for basic properties |
| |
| The use of the `@Resource` annotation isn’t limited to setters. For |
| example, this annotation could have been used on the corresponding |
| _field_ like so: |
| |
| [source,java] |
| ---- |
| @Resource |
| private int maxLineItems; |
| ---- |
| |
| A fuller example might look like this: |
| |
| [source,java] |
| ---- |
| package org.superbiz.injection.enventry; |
| |
| import javax.annotation.Resource; |
| import javax.ejb.Singleton; |
| import java.util.Date; |
| |
| @Singleton |
| public class Configuration { |
| |
| @Resource |
| private String color; |
| |
| @Resource |
| private Shape shape; |
| |
| @Resource |
| private Class strategy; |
| |
| @Resource(name = "date") |
| private long date; |
| |
| public String getColor() { |
| return color; |
| } |
| |
| public Shape getShape() { |
| return shape; |
| } |
| |
| public Class getStrategy() { |
| return strategy; |
| } |
| |
| public Date getDate() { |
| return new Date(date); |
| } |
| } |
| ---- |
| |
| Here we have an `@Singleton` bean called `Configuration` that has the |
| following properties (`<env-entry>` items) |
| |
| * String color |
| * Shape shape |
| * Class strategy |
| * long date |
| |
| === Supplying @Resource values for items in ejb-jar.xml |
| |
| The values for our `color`, `shape`, `strategy` and `date` properties |
| are supplied via `<env-entry>` elements in the `ejb-jar.xml` file or the |
| `web.xml` file like so: |
| |
| [source,xml] |
| ---- |
| <ejb-jar xmlns="http://java.sun.com/xml/ns/javaee" version="3.0" metadata-complete="false"> |
| <enterprise-beans> |
| <session> |
| <ejb-name>Configuration</ejb-name> |
| <env-entry> |
| <env-entry-name>org.superbiz.injection.enventry.Configuration/color</env-entry-name> |
| <env-entry-type>java.lang.String</env-entry-type> |
| <env-entry-value>orange</env-entry-value> |
| </env-entry> |
| <env-entry> |
| <env-entry-name>org.superbiz.injection.enventry.Configuration/shape</env-entry-name> |
| <env-entry-type>org.superbiz.injection.enventry.Shape</env-entry-type> |
| <env-entry-value>TRIANGLE</env-entry-value> |
| </env-entry> |
| <env-entry> |
| <env-entry-name>org.superbiz.injection.enventry.Configuration/strategy</env-entry-name> |
| <env-entry-type>java.lang.Class</env-entry-type> |
| <env-entry-value>org.superbiz.injection.enventry.Widget</env-entry-value> |
| </env-entry> |
| <env-entry> |
| <description>The name was explicitly set in the annotation so the classname prefix isn't required</description> |
| <env-entry-name>date</env-entry-name> |
| <env-entry-type>java.lang.Long</env-entry-type> |
| <env-entry-value>123456789</env-entry-value> |
| </env-entry> |
| </session> |
| </enterprise-beans> |
| </ejb-jar> |
| ---- |
| |
| ==== Using the @Resource `name' attribute |
| |
| Note that `date` was referenced by `name` as: |
| |
| [source,java] |
| ---- |
| @Resource(name = "date") |
| private long date; |
| ---- |
| |
| When the `@Resource(name)` is used, you do not need to specify the full |
| class name of the bean and can do it briefly like so: |
| |
| [source,java] |
| ---- |
| <env-entry> |
| <description>The name was explicitly set in the annotation so the classname prefix isn't required</description> |
| <env-entry-name>date</env-entry-name> |
| <env-entry-type>java.lang.Long</env-entry-type> |
| <env-entry-value>123456789</env-entry-value> |
| </env-entry> |
| ---- |
| |
| Conversly, `color` was not referenced by `name` |
| |
| [source,java] |
| ---- |
| @Resource |
| private String color; |
| ---- |
| |
| When something is not referenced by `name` in the `@Resource` annotation |
| a default name is created. The format is essentially this: |
| |
| [source,java] |
| ---- |
| bean.getClass() + "/" + field.getName() |
| ---- |
| |
| So the default `name` of the above `color` property ends up being |
| `org.superbiz.injection.enventry.Configuration/color`. This is the name |
| we must use when we attempt to decalre a value for it in xml. |
| |
| [source,java] |
| ---- |
| <env-entry> |
| <env-entry-name>org.superbiz.injection.enventry.Configuration/color</env-entry-name> |
| <env-entry-type>java.lang.String</env-entry-type> |
| <env-entry-value>orange</env-entry-value> |
| </env-entry> |
| ---- |
| |
| ==== @Resource and Enum (Enumerations) |
| |
| The `shape` field is actually a custom Java Enum type |
| |
| [source,java] |
| ---- |
| package org.superbiz.injection.enventry; |
| |
| public enum Shape { |
| |
| CIRCLE, |
| TRIANGLE, |
| SQUARE |
| } |
| ---- |
| |
| As of Java EE 6, java.lang.Enum types are allowed as `<env-entry>` |
| items. Declaring one in xml is done using the actual enum’s class name |
| like so: |
| |
| [source,java] |
| ---- |
| <env-entry> |
| <env-entry-name>org.superbiz.injection.enventry.Configuration/shape</env-entry-name> |
| <env-entry-type>org.superbiz.injection.enventry.Shape</env-entry-type> |
| <env-entry-value>TRIANGLE</env-entry-value> |
| </env-entry> |
| ---- |
| |
| Do not use `<env-entry-type>java.lang.Enum</env-entry-type>` or it will |
| not work! |
| |
| === ConfigurationTest |
| |
| [source,java] |
| ---- |
| package org.superbiz.injection.enventry; |
| |
| import junit.framework.TestCase; |
| |
| import javax.ejb.embeddable.EJBContainer; |
| import javax.naming.Context; |
| import java.util.Date; |
| |
| public class ConfigurationTest extends TestCase { |
| |
| |
| public void test() throws Exception { |
| final Context context = EJBContainer.createEJBContainer().getContext(); |
| |
| final Configuration configuration = (Configuration) context.lookup("java:global/injection-of-env-entry/Configuration"); |
| |
| assertEquals("orange", configuration.getColor()); |
| |
| assertEquals(Shape.TRIANGLE, configuration.getShape()); |
| |
| assertEquals(Widget.class, configuration.getStrategy()); |
| |
| assertEquals(new Date(123456789), configuration.getDate()); |
| } |
| } |
| ---- |
| |
| == Running |
| |
| [source,console] |
| ---- |
| ------------------------------------------------------- |
| T E S T S |
| ------------------------------------------------------- |
| Running org.superbiz.injection.enventry.ConfigurationTest |
| Apache OpenEJB 4.0.0-beta-1 build: 20111002-04:06 |
| http://tomee.apache.org/ |
| INFO - openejb.home = /Users/dblevins/examples/injection-of-env-entry |
| INFO - openejb.base = /Users/dblevins/examples/injection-of-env-entry |
| INFO - Using 'javax.ejb.embeddable.EJBContainer=true' |
| 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 - Found EjbModule in classpath: /Users/dblevins/examples/injection-of-env-entry/target/classes |
| INFO - Beginning load: /Users/dblevins/examples/injection-of-env-entry/target/classes |
| INFO - Configuring enterprise application: /Users/dblevins/examples/injection-of-env-entry |
| WARN - Method 'lookup' is not available for 'javax.annotation.Resource'. Probably using an older Runtime. |
| INFO - Configuring Service(id=Default Singleton Container, type=Container, provider-id=Default Singleton Container) |
| INFO - Auto-creating a container for bean Configuration: Container(type=SINGLETON, id=Default Singleton Container) |
| INFO - Configuring Service(id=Default Managed Container, type=Container, provider-id=Default Managed Container) |
| INFO - Auto-creating a container for bean org.superbiz.injection.enventry.ConfigurationTest: Container(type=MANAGED, id=Default Managed Container) |
| INFO - Enterprise application "/Users/dblevins/examples/injection-of-env-entry" loaded. |
| INFO - Assembling app: /Users/dblevins/examples/injection-of-env-entry |
| INFO - Jndi(name="java:global/injection-of-env-entry/Configuration!org.superbiz.injection.enventry.Configuration") |
| INFO - Jndi(name="java:global/injection-of-env-entry/Configuration") |
| INFO - Jndi(name="java:global/EjbModule1355224018/org.superbiz.injection.enventry.ConfigurationTest!org.superbiz.injection.enventry.ConfigurationTest") |
| INFO - Jndi(name="java:global/EjbModule1355224018/org.superbiz.injection.enventry.ConfigurationTest") |
| INFO - Created Ejb(deployment-id=org.superbiz.injection.enventry.ConfigurationTest, ejb-name=org.superbiz.injection.enventry.ConfigurationTest, container=Default Managed Container) |
| INFO - Created Ejb(deployment-id=Configuration, ejb-name=Configuration, container=Default Singleton Container) |
| INFO - Started Ejb(deployment-id=org.superbiz.injection.enventry.ConfigurationTest, ejb-name=org.superbiz.injection.enventry.ConfigurationTest, container=Default Managed Container) |
| INFO - Started Ejb(deployment-id=Configuration, ejb-name=Configuration, container=Default Singleton Container) |
| INFO - Deployed Application(path=/Users/dblevins/examples/injection-of-env-entry) |
| Tests run: 1, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 1.664 sec |
| |
| Results : |
| |
| Tests run: 1, Failures: 0, Errors: 0, Skipped: 0 |
| ---- |