THIS IS A TEST INSTANCE. ALL YOUR CHANGES WILL BE LOST!!!!
Overview
This example demonstrates the use of the injection of environment entries using @Resource annotation.
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$ cd <openejb3_project_dir>/examples/resource-injection
$ mvn clean install
The Code
Injection through field
maxLineItem field in PurchaseOrderBean class is annotated with @Resource annotation to inject a simple environment entry. Default value of10 is assigned. Deployer can modify the values of the environment entries at deploy time in deployment descriptor.
@Resource annotation of a field
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@Resource int maxLineItems = 10; |
Injection through a setter method
setMaxLineItem method in InvioceBean class is annotated with @Resource annotation to inject a simple environment entry. By default, the JavaBeans propery name is combined with the name of the class in which the annotation is used and is used directly as the name in the bean's naming context. JNDI name for this entry would be:
- java:comp/env/org.apache.openejb.examples.resource.InvoiceBean/maxLineItems
@Resource annotation of a setter method
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@Resource
public void setMaxLineItems(int maxLineItems) {
this.maxLineItems = maxLineItems;
}
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env-entry in ejb-jar.xml
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<env-entry>
<description>The maximum number of line items per invoice.</description>
<env-entry-name>org.apache.openejb.examples.injection.InvoiceBean/maxLineItems</env-entry-name>
<env-entry-type>java.lang.Integer</env-entry-type>
<env-entry-value>15</env-entry-value>
</env-entry>
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Using @Resource annotated env-entry
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maxLineItems variable is injected by the setMaxLine method above. See also how env-entry is defined in ejb-jar.xml |
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public void addLineItem(LineItem item) throws TooManyItemsException {
if (item == null) {
throw new IllegalArgumentException("Line item must not be null");
}
if (itemCount <= maxLineItems) {
items.add(item);
itemCount++;
} else {
throw new TooManyItemsException("Number of items exceeded the maximum limit");
}
}
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JUnit Test
Writing an JUnit test for this example is quite simple. We need just to write a setup method to create and initialize the InitialContext, and then write our test methods.
Test fixture
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protected void setUp() throws Exception {
Properties properties = new Properties();
properties.setProperty(Context.INITIAL_CONTEXT_FACTORY, "org.apache.openejb.client.LocalInitialContextFactory");
properties.setProperty("openejb.deployments.classpath.include", ".*resource-injection.*");
initialContext = new InitialContext(properties);
}
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Test methods
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public void testAddLineItem() throws Exception {
Invoice order = (Invoice) initialContext.lookup("InvoiceBeanBusinessRemote");
assertNotNull(order);
LineItem item = new LineItem("ABC-1", "Test Item");
try {
order.addLineItem(item);
} catch (TooManyItemsException tmie) {
fail("Test failed due to: " + tmie.getMessage());
}
}
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Running
Running the example is fairly simple. Just execute the following commands:
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