Package edu.ucsb.nceas.metacat.index.queue

Class IndexGenerator

java.lang.Object

edu.ucsb.nceas.metacat.shared.BaseService

edu.ucsb.nceas.metacat.index.queue.IndexGenerator

public class IndexGenerator
extends BaseService

The IndexGenerator class will publish (send) the index information to a RabbitMQ queue. A index worker will consume the information.

Author:

tao

Field Summary

Fields

Modifier and Type	Field	Description
static final String	CREATE_INDEX_TYPE
static final String	DELETE_INDEX_TYPE
static final int	HIGH_PRIORITY
static final int	HIGHEST_PRIORITY
static final int	LOW_PRIORITY
static final int	MEDIUM_PRIORITY
static final int	MEDIUM_RESOURCEMAP_PRIORITY
static final String	SYSMETA_CHANGE_TYPE

Fields inherited from class edu.ucsb.nceas.metacat.shared.BaseService

_serviceName

Method Summary

Modifier and Type	Method	Description
protected void	doRefresh()
protected static String	getFilePath(org.dataone.service.types.v1.Identifier id)	Get the relative file path for the identifier.
static IndexGenerator	getInstance()	Implement a Singleton pattern using "double checked locking" pattern.
protected static String	getLastSubdir(String path)	Get the last sub-directory in the path.
void	publish(org.dataone.service.types.v1.Identifier id, String index_type, int priority)	Publish the given information to the index queue
boolean	refreshable()	This service is not refreshable
static void	refreshInstance()	This method sets the instance to null and forces the getInstance method to create a new instance.
int	size()	Get the number of messages in the index queue
void	stop()	Stop the service

Methods inherited from class edu.ucsb.nceas.metacat.shared.BaseService

refresh

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

CREATE_INDEX_TYPE

public static final String CREATE_INDEX_TYPE

See Also:

• Constant Field Values

DELETE_INDEX_TYPE

public static final String DELETE_INDEX_TYPE

See Also:

• Constant Field Values

SYSMETA_CHANGE_TYPE

public static final String SYSMETA_CHANGE_TYPE

See Also:

• Constant Field Values

HIGHEST_PRIORITY

public static final int HIGHEST_PRIORITY

See Also:

• Constant Field Values

HIGH_PRIORITY

public static final int HIGH_PRIORITY

See Also:

• Constant Field Values

MEDIUM_PRIORITY

public static final int MEDIUM_PRIORITY

See Also:

• Constant Field Values

MEDIUM_RESOURCEMAP_PRIORITY

public static final int MEDIUM_RESOURCEMAP_PRIORITY

See Also:

• Constant Field Values

LOW_PRIORITY

public static final int LOW_PRIORITY

See Also:

• Constant Field Values

Method Details

getLastSubdir

protected static String getLastSubdir(String path)

Get the last sub-directory in the path. If the path is /var/data, data will be returned.

Parameters:

path - the path will be analyzed.

Returns:

the last part of path

getInstance

public static IndexGenerator getInstance()
                                  throws ServiceException

Implement a Singleton pattern using "double checked locking" pattern.

Returns:

a singleton instance of the RabbitMQService class.

Throws:

ServiceException

refreshInstance

public static void refreshInstance()

This method sets the instance to null and forces the getInstance method to create a new instance. This method is only used for a testing purpose!

publish

public void publish(org.dataone.service.types.v1.Identifier id,
 String index_type,
 int priority)
             throws ServiceException,
org.dataone.service.exceptions.InvalidRequest

Publish the given information to the index queue

Parameters:

id - the identifier of the object which will be indexed

index_type - the type of indexing, it can be delete, create or sysmeta

priority - the priority of the index task

Throws:

ServiceException

org.dataone.service.exceptions.InvalidRequest

getFilePath

protected static String getFilePath(org.dataone.service.types.v1.Identifier id)
                             throws ServiceException

Get the relative file path for the identifier. This relative path is based on application.datafilepath (for data files) or application.documentfilepath (for document files) For example, autogen.1.1 is the docid for guid foo.1 and it is a metadata object. The metadata objects are stored in the path /var/metacat/document/autogen.1.1. Since the application.documentfilepath is "/var/metacat/document", the relative file path will be autogen.1.1. Note, the value can be null since cn doesn't store data objects.

Parameters:

id - the guid of object

Returns:

the relative file path

Throws:

ServiceException

refreshable

public boolean refreshable()

This service is not refreshable

Specified by:

refreshable in class BaseService

doRefresh

protected void doRefresh()
                  throws ServiceException

Specified by:

doRefresh in class BaseService

Throws:

ServiceException

stop

public void stop()
          throws ServiceException

Stop the service

Specified by:

stop in class BaseService

Throws:

ServiceException

size

public int size()

Get the number of messages in the index queue

Returns:

the number of messages