lbg.protocol.api
Interface GridApplication

All Known Implementing Classes:

GridHasher, HelloGrid, SimTask

public interface GridApplication

This interface must be implemented by one class in each Grid application submitted as a Task.

This class must implement:

• A constructor without any arguments
• A method to receive its input parameters
• A method to receive its input data files
• A method to receive the id of the Supplier Peer that controls the Resource running it
• A method to be started
• A method to export its results

These methods will always be called in that order. If your application does not need one or both of the offered inputs, it should still provide the methods, which will be empty. getResult() can be called more than once.

Author:

Xavier Dalem, Cyril Briquet

Method Summary

void	compute() Runs the Grid application.
byte[]	getResult() Gets computed results.
void	setInputData(GridData[] datas) Sets the Grid application's input data files.
void	setParameters(java.lang.Object[] parameters) Sets the Grid application's input parameters.
void	setPlaypen(java.lang.String playpen_dir) Sets the playpen directory of the Resource where the Grid application can write and read temporary files.
void	setSupplier(java.lang.String supplier_id) Sets the id of the Supplier Peer that controls the Resource running the Grid application

Method Detail

setParameters

void setParameters(java.lang.Object[] parameters)
                   throws GridException

Sets the Grid application's input parameters.

Parameters:

parameters - An array of parameters as Objects. Can be empty, but never null.

Throws:

GridException - If the parameters are not what they should be.

setInputData

void setInputData(GridData[] datas)
                  throws GridException

Sets the Grid application's input data files.

Parameters:

datas - All input datas

Throws:

GridException - If the data is not what it should be.

setSupplier

void setSupplier(java.lang.String supplier_id)
                 throws GridException

Sets the id of the Supplier Peer that controls the Resource running the Grid application

Parameters:

supplier_id - Supplier Peer id

Throws:

GridException - If the Supplier Peer id is not what it should be.

setPlaypen

void setPlaypen(java.lang.String playpen_dir)
                throws GridException

Sets the playpen directory of the Resource where the Grid application can write and read temporary files.

Parameters:

playpen_dir - playpen directory

Throws:

GridException - If the playpen directory is not what it should be.

getResult

byte[] getResult()

Gets computed results.

Note: if no results are produced, new byte[0] can be used as a legal value.

Returns:

computed results, or null if a transient error happened

compute

void compute()

Runs the Grid application. As this method cannot throw any exception, one should print his stack traces to stderr in case of error. They will be returned in the logs if the application completes (i.e. doesn't fail elsewhere).