org.odpi.openmetadata.frameworks.connectors

Class ConnectorBase

java.lang.Object

org.odpi.openmetadata.frameworks.connectors.Connector

org.odpi.openmetadata.frameworks.connectors.ConnectorBase

public abstract class ConnectorBase
extends Connector

The ConnectorBase is an implementation of the Connector interface. Connectors are client-side interfaces to assets such as data stores, data sets, APIs, analytical functions. They handle the communication with the server that hosts the assets, along with the communication with the metadata server to serve up metadata about the assets, and support for an audit log for the caller to log its activity. Each connector implementation is paired with a connector provider. The connector provider is the factory for connector instances. The Connector interface defines that a connector instance should be able to return a unique identifier, a connection object and a metadata properties object for its connected asset. These are supplied to the connector during its initialization. The ConnectorBase base class implements all of the methods required by the Connector interface. Each specific implementation of a connector then extends this interface to add the methods to work with the particular type of asset it supports. For example, a JDBC connector would add the standard JDBC SQL interface, the OMRS Connectors add the metadata repository management APIs...

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected class	ConnectorBase.ProtectedConnection ProtectedConnection provides a subclass to Connection in order to extract protected values from the connection in order to supply them to the Connector implementation.

Field Summary

Fields

Modifier and Type	Field and Description
protected ConnectedAssetProperties	connectedAssetProperties
protected Connection	connectionBean
protected ConnectionProperties	connectionProperties
protected String	connectorInstanceId
protected boolean	isActive
protected Map<String,Object>	securedProperties

Constructor Summary

Constructors

Constructor and Description
ConnectorBase() Typical Constructor: Connectors should always have a constructor requiring no parameters and perform initialization in the initialize method.

Method Summary

Modifier and Type	Method and Description
void	disconnect() Free up any resources held since the connector is no longer needed.
boolean	equals(Object object) Provide a common implementation of equals for all OCF Connector Provider objects.
ConnectedAssetProperties	getConnectedAssetProperties(String userId) Returns the properties that contain the metadata for the asset.
ConnectionProperties	getConnection() Returns the connection object that was used to create the connector instance.
String	getConnectorInstanceId() Returns the unique connector instance id that assigned to the connector instance when it was created.
int	hashCode() Provide a common implementation of hashCode for all OCF Connector objects.
void	initialize(String connectorInstanceId, ConnectionProperties connectionProperties) Call made by the ConnectorProvider to initialize the Connector with the base services.
void	initializeConnectedAssetProperties(ConnectedAssetProperties connectedAssetProperties) Set up the connected asset properties object.
boolean	isActive() Return a flag indicating whether the connector is active.
void	start() Indicates that the connector is completely configured and can begin processing.
String	toString() Standard toString method.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

connectorInstanceId

protected String connectorInstanceId

connectionProperties

protected ConnectionProperties connectionProperties

connectionBean

protected Connection connectionBean

connectedAssetProperties

protected ConnectedAssetProperties connectedAssetProperties

isActive

protected boolean isActive

securedProperties

protected Map<String,Object> securedProperties

Constructor Detail

ConnectorBase

public ConnectorBase()

Typical Constructor: Connectors should always have a constructor requiring no parameters and perform initialization in the initialize method.

Method Detail

initialize

public void initialize(String connectorInstanceId,
                       ConnectionProperties connectionProperties)

Call made by the ConnectorProvider to initialize the Connector with the base services.

Specified by:

initialize in class Connector

Parameters:

connectorInstanceId - unique id for the connector instance useful for messages etc

connectionProperties - POJO for the configuration used to create the connector.

getConnectorInstanceId

public String getConnectorInstanceId()

Returns the unique connector instance id that assigned to the connector instance when it was created. It is useful for error and audit messages.

Specified by:

getConnectorInstanceId in class Connector

Returns:

guid for the connector instance

getConnection

public ConnectionProperties getConnection()

Returns the connection object that was used to create the connector instance. Its contents are never refreshed during the lifetime of the connector instance, even if the connection information is updated or removed from the originating metadata repository.

Specified by:

getConnection in class Connector

Returns:

connection properties object

initializeConnectedAssetProperties

public void initializeConnectedAssetProperties(ConnectedAssetProperties connectedAssetProperties)

Set up the connected asset properties object. This provides the known metadata properties stored in one or more metadata repositories. The properties are populated whenever getConnectedAssetProperties() is called.

Specified by:

initializeConnectedAssetProperties in class Connector

Parameters:

connectedAssetProperties - properties of the connected asset

getConnectedAssetProperties

public ConnectedAssetProperties getConnectedAssetProperties(String userId)
                                                     throws PropertyServerException,
                                                            UserNotAuthorizedException

Returns the properties that contain the metadata for the asset. The asset metadata is retrieved from the metadata repository and cached in the ConnectedAssetProperties object each time the getConnectedAssetProperties method is requested by the caller. Once the ConnectedAssetProperties object has the metadata cached, it can be used to access the asset property values many times without a return to the metadata repository. The cache of metadata can be refreshed simply by calling this getConnectedAssetProperties() method again.

Specified by:

getConnectedAssetProperties in class Connector

Parameters:

userId - userId of requesting user

Returns:

ConnectedAssetProperties connected asset properties

Throws:

PropertyServerException - indicates a problem retrieving properties from a metadata repository

UserNotAuthorizedException - indicates that the user is not authorized to access the asset properties.

start

public void start()
           throws ConnectorCheckedException

Indicates that the connector is completely configured and can begin processing.

Specified by:

start in class Connector

Throws:

ConnectorCheckedException - there is a problem within the connector.

disconnect

public void disconnect()
                throws ConnectorCheckedException

Free up any resources held since the connector is no longer needed.

Specified by:

disconnect in class Connector

Throws:

ConnectorCheckedException - there is a problem within the connector.

isActive

public boolean isActive()

Return a flag indicating whether the connector is active. This means it has been started and not yet disconnected.

Returns:

isActive flag

hashCode

public int hashCode()

Provide a common implementation of hashCode for all OCF Connector objects. The UUID is unique and is randomly assigned and so its hashCode is as good as anything to describe the hash code of the connector object.

Overrides:

hashCode in class Object

Returns:

random UUID as hashcode

equals

public boolean equals(Object object)

Provide a common implementation of equals for all OCF Connector Provider objects. The UUID is unique and is randomly assigned and so its hashCode is as good as anything to evaluate the equality of the connector provider object.

Overrides:

equals in class Object

Parameters:

object - object to test

Returns:

boolean flag

toString

public String toString()

Standard toString method.

Overrides:

toString in class Object

Returns:

print out of variables in a JSON-style