org.apache.deltaspike.core.api.projectstage.ProjectStage Maven / Gradle / Ivy
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* to you under the Apache License, Version 2.0 (the
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*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
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* under the License.
*/
package org.apache.deltaspike.core.api.projectstage;
import org.apache.deltaspike.core.util.ServiceUtils;
import javax.enterprise.inject.Typed;
import java.io.Serializable;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.logging.Logger;
/**
* This class is the base of all ProjectStages. A ProjectStage
* identifies the environment the application currently runs in.
* It provides the same functionality as the JSF-2 ProjectStage
* but has a few additional benefits:
*
* - it also works for JSF-1.0, JSF-1.1 and JSF-1.2 applications
* - it also works in pure backends and unit tests without any faces-api
* - it is dynamic. Everyone can add their own ProjectStages!
*
*
*
* Technically this is kind of a 'dynamic enum'.
* The following ProjectStages are provided by default
*
* - UnitTest
* - Development
* - SystemTest
* - IntegrationTest
* - Staging
* - Production
*
*
* The following resolution mechanism is used to determine the current ProjectStage:
*
* - TODO specify!
*
*
*
* Adding a new ProjectStage is done via the
* {@link java.util.ServiceLoader} mechanism. A class deriving from {@link ProjectStage}
* must be provided and used for creating a single static instance of it.
*
*
Custom ProjectStages can be implemented by writing anonymous ProjectStage
* members into a registered {@link ProjectStageHolder} as shown in the following
* sample:
*
* package org.apache.deltaspike.test.core.api.projectstage;
* public class TestProjectStages implements ProjectStageHolder {
* public static final class MyOwnProjectStage extends ProjectStage {};
* public static final MyOwnProjectStage MyOwnProjectStage = new MyOwnProjectStage();
*
* public static final class MyOtherProjectStage extends ProjectStage {};
* public static final MyOtherProjectStage MyOtherProjectStage = new MyOtherProjectStage();
* }
*
* For activating those ProjectStages, you have to register this ProjectStageHolder class
* to get picked up via the java.util.ServiceLoader mechanism. Simply create a file
*
* META-INF/services/org.apache.deltaspike.core.api.projectstage.ProjectStageHolder
*
* which contains the fully qualified class name of custom ProjectStageHolder implementation:
*
* # this class now gets picked up by java.util.ServiceLoader
* org.apache.deltaspike.test.core.api.projectstage.TestProjectStages
*
*
* You can use your own ProjectStages exactly the same way as all the ones provided
* by the system:
*
* ProjectStage myOwnPs = ProjectStage.valueOf("MyOwnProjectStage");
if (myOwnPs.equals(MyOwnProjectStage.MyOwnProjectStage)) ...
*
*
* Note: Please note that DeltaSpike will only find {@link ProjectStageHolder}s
* which are accessible by this very class. If you deploy the deltaspike-core jar to a
* shared EAR classloader, it will e.g. not be able to register ProjectStages defined
* in a web applications WEB-INF/classes directory!
*
*
*/
@Typed()
public abstract class ProjectStage implements Serializable
{
private static final long serialVersionUID = -1210639662598734888L;
/**
* This map contains a static map with all registered projectStages.
*
* We don't need to use a ConcurrentHashMap because writing to it will
* only be performed in the static initializer block which is guaranteed
* to be atomic by the VM spec.
*/
private static Map projectStages = new HashMap();
/**
* All the registered ProjectStage values.
* We don't need to make this volatile because of the classloader guarantees of
* the VM.
*/
private static ProjectStage[] values = null;
/**
* logger for the ProjectStage
*/
private static final Logger LOG = Logger.getLogger(ProjectStage.class.getName());
/**
* The static initializer block will register all custom ProjectStages
* by simply touching their classes due loading it with the.
* {@link java.util.ServiceLoader}.
*/
static
{
List projectStageHolders =
ServiceUtils.loadServiceImplementations(ProjectStageHolder.class);
for (ProjectStageHolder projectStageHolder : projectStageHolders)
{
LOG.fine("registering ProjectStages from ProjectStageHolder " + projectStageHolder.getClass().getName());
}
}
/** the name of the ProjectStage*/
private String psName;
/**
* The protected constructor will register the given ProjectStage via its name.
* The name is returned by the {@link #toString()} method of the ProjectStage.
*/
protected ProjectStage()
{
String projectStageClassName = getClass().getSimpleName();
psName = projectStageClassName;
init(projectStageClassName, this);
}
/**
* This function exists to prevent findbugs to complain about
* setting a static member from a non-static function.
*
* @param projectStageClassName name of the project-stage
* @param projectStage instance of the project-stage
*/
private static void init(String projectStageClassName, ProjectStage projectStage)
{
if (!projectStages.containsKey(projectStageClassName))
{
projectStages.put(projectStageClassName, projectStage);
}
else
{
throw new IllegalArgumentException("ProjectStage with name " + projectStageClassName + " already exists!");
}
// we cannot do this in the static block since it's not really deterministic
// when all ProjectStages got resolved.
values = projectStages.values().toArray(new ProjectStage[ projectStages.size() ]);
}
/**
* @param projectStageClassName the name of the ProjectStage
* @return the ProjectStage which is identified by it's name
*/
public static ProjectStage valueOf(String projectStageClassName)
{
return projectStages.get(projectStageClassName);
}
/**
* Exposes all registered {@link ProjectStage} implementations
* @return provided and custom project-stage implementations
*/
public static ProjectStage[] values()
{
ProjectStage[] result = new ProjectStage[values.length];
System.arraycopy(values, 0, result, 0, values.length);
return result;
}
/**
* {@inheritDoc}
*/
@Override
public String toString()
{
return psName;
}
// CHECKSTYLE:OFF
/**
* Project-stage for unit-tests
*/
@Typed()
public static final class UnitTest extends ProjectStage implements TestStage
{
private static final long serialVersionUID = -7910349894182034559L;
}
/**
* Type-safe {@link ProjectStage}
*/
public static final UnitTest UnitTest = new UnitTest();
/**
* Project-stage for development
*/
@Typed()
public static final class Development extends ProjectStage
{
private static final long serialVersionUID = 1977308277341527250L;
}
/**
* Type-safe {@link ProjectStage}
*/
public static final Development Development = new Development();
/**
* Project-stage for system-tests
*/
@Typed()
public static final class SystemTest extends ProjectStage implements TestStage
{
private static final long serialVersionUID = -7444003351466372539L;
}
/**
* Type-safe {@link ProjectStage}
*/
public static final SystemTest SystemTest = new SystemTest();
/**
* Project-stage for integration-tests
*/
@Typed()
public static final class IntegrationTest extends ProjectStage implements TestStage
{
private static final long serialVersionUID = 2034474361615347127L;
}
/**
* Type-safe {@link ProjectStage}
*/
public static final IntegrationTest IntegrationTest = new IntegrationTest();
/**
* Project-stage for staging
*/
@Typed()
public static final class Staging extends ProjectStage
{
private static final long serialVersionUID = -8426149532860809553L;
}
/**
* Type-safe {@link ProjectStage}
*/
public static final Staging Staging = new Staging();
/**
* Default project-stage for production
*/
@Typed()
public static final class Production extends ProjectStage
{
private static final long serialVersionUID = -4030601958667812084L;
}
/**
* Type-safe {@link ProjectStage}
*/
public static final Production Production = new Production();
// CHECKSTYLE:ON
}