cgl.hpsearch.wsproxy
Class ProxyWebService

java.lang.Object
  cgl.hpsearch.wsproxy.ProxyWebService

Direct Known Subclasses:

RunnableProxyWebService, WrapperProxyWebService

public abstract class ProxyWebService

extends Object

A Proxy Service that serves as a wrapper to other webservices that need to be hosted.
Created: May 14, 2004

Author:

Harshawardhan Gadgil (hgadgil@grids.ucs.indiana.edu)

Field Summary

InvocationContainer	container
static int	INCORRECT_PARAMETERS
static int	INIT_FAILURE
static int	INIT_SUCCESS
static int	INVOCATION_ERROR
static int	SERVICE_DONE
static int	SERVICE_FINISHED
static int	SERVICE_NOT_FOUND
static int	SERVICE_READY
static int	SERVICE_RUNNING
static String[]	SERVICE_STATUS
static int	SERVICE_STOPPED
static int	SERVICE_SUSPENDED
static int	SERVICE_TERMINATED
String	serviceName

Constructor Summary

ProxyWebService()

Method Summary

void	cleanup()
String[]	getContext(String contextURI) Retrieves the context data from the location specified by contextURI
String	getNewTemporaryFileName()
String	getProperty(String name) Returns the value of the property
int	getStatus()
void	handleException(Exception e) Safe error handler for handling processing errors.
abstract void	initService(InputStream[] in, OutputStream[] out) Should be used by services to set the i/p and o/p streams.
abstract void	process() Other services MUST override this.
void	registerTemporaryFile(String tmpFileName)
abstract void	resumeService()
abstract String[]	serviceExceptions() An array of possible exceptions that can happen when the service is running.
void	serviceFinished() Indicates that the service has done processing.
String	setContext(String contextURI, String[] data) Stores the context data in teh location specified by contextURI
void	setInvocationHandler(String invokedService, InvocationContainer ic) Must be called by the InvocationContainer to specify which service is being run and a pointer to the InvocationConatainer.
void	setLogEntry(String entry) Sets the logging entry
void	setProperty(String name, String value) Sets the service's system property
void	setStatus(int _status) Provides a way for setting the service status.
abstract void	startService()
abstract void	stopService()
abstract void	suspendService()

Methods inherited from class java.lang.Object

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

Field Detail

INVOCATION_ERROR

public static final int INVOCATION_ERROR

See Also:

Constant Field Values

INCORRECT_PARAMETERS

public static final int INCORRECT_PARAMETERS

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Constant Field Values

SERVICE_NOT_FOUND

public static final int SERVICE_NOT_FOUND

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Constant Field Values

INIT_FAILURE

public static final int INIT_FAILURE

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Constant Field Values

INIT_SUCCESS

public static final int INIT_SUCCESS

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Constant Field Values

SERVICE_READY

public static final int SERVICE_READY

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Constant Field Values

SERVICE_RUNNING

public static final int SERVICE_RUNNING

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Constant Field Values

SERVICE_SUSPENDED

public static final int SERVICE_SUSPENDED

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Constant Field Values

SERVICE_FINISHED

public static final int SERVICE_FINISHED

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Constant Field Values

SERVICE_STOPPED

public static final int SERVICE_STOPPED

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Constant Field Values

SERVICE_TERMINATED

public static final int SERVICE_TERMINATED

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Constant Field Values

SERVICE_DONE

public static final int SERVICE_DONE

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Constant Field Values

SERVICE_STATUS

public static final String[] SERVICE_STATUS

container

public InvocationContainer container

serviceName

public String serviceName

Constructor Detail

ProxyWebService

public ProxyWebService()

Method Detail

process

public abstract void process()
                      throws Exception

Other services MUST override this. This defines the unit of execution of the service.

Throws:

Exception

initService

public abstract void initService(InputStream[] in,
                                 OutputStream[] out)

Should be used by services to set the i/p and o/p streams.

Parameters:

in - - An array containing input streams used by the service

out - - An array containing output streams used by the service

serviceExceptions

public abstract String[] serviceExceptions()

An array of possible exceptions that can happen when the service is running. This may be as simple as java.io.Exception or may be even more verbose and lists out all possible exceptions.

Returns:

An array of String containing the possible exceptions to be caught.

setInvocationHandler

public final void setInvocationHandler(String invokedService,
                                       InvocationContainer ic)

Must be called by the InvocationContainer to specify which service is being run and a pointer to the InvocationConatainer.

Parameters:

invokedService - - Name of the service

ic - - Pointer to the invocation Container.

getStatus

public final int getStatus()

Returns:

The current status of the service

setStatus

public final void setStatus(int _status)

Provides a way for setting the service status. Services extending the RunnableProxyWebService can use this function to set the status during initialization stage.

Parameters:

_status -

setProperty

public final void setProperty(String name,
                              String value)

Sets the service's system property

Parameters:

name - Name of the property

value - Value to be set

getProperty

public final String getProperty(String name)

Returns the value of the property

Parameters:

name - The property being queried

Returns:

The value of the property specified by name

setLogEntry

public final void setLogEntry(String entry)

Sets the logging entry

Parameters:

entry - The log entry

setContext

public final String setContext(String contextURI,
                               String[] data)

Stores the context data in teh location specified by contextURI

Parameters:

contextURI - - The context location

data - - the data to store

Returns:

getContext

public final String[] getContext(String contextURI)

Retrieves the context data from the location specified by contextURI

Returns:

retrieved data, "NULL" if nothing found

cleanup

public final void cleanup()

getNewTemporaryFileName

public String getNewTemporaryFileName()

registerTemporaryFile

public void registerTemporaryFile(String tmpFileName)

serviceFinished

public final void serviceFinished()

Indicates that the service has done processing.

handleException

public final void handleException(Exception e)

Safe error handler for handling processing errors. This calls the InvocationContainer's logging function to notify the error and then suspends the execution.
Any other exceptions while suspending the thread are ignored.
TODO: Change the format for conveying error. Maybe enclose it in some XML structure

Parameters:

e - - The error that occurred while processing.

startService

public abstract void startService()
                           throws Exception

Throws:

Exception

stopService

public abstract void stopService()
                          throws Exception

Throws:

Exception

suspendService

public abstract void suspendService()
                             throws Exception

Throws:

Exception

resumeService

public abstract void resumeService()
                            throws Exception

Throws:

Exception