sv.graph
Class DataSource

java.lang.Object
  sv.graph.DataSource

public class DataSource

extends java.lang.Object

An application that provides data for display must register with ElVis. The application only sends data to one copy of the program. The application does not know about any of the collaborators. The collaboration server will forward the data to collaborating programs. ElVis has a window where the user selects which data sources to receive.

Field Summary

static int

DEFAULT_PORT

Constructor Summary

DataSource()

DataSource(java.lang.String sourceName, java.lang.String inUser, java.lang.String inID)
Define the application that will send data to ElVis.

Method Summary

boolean	appendFile(java.lang.String filename) Append to a GraphWindow file.
boolean	closeFile() Close the currently open GraphWindow file.
boolean	closeFile(boolean poll) Close the currently open GraphWindow file and specify client polling.
void	closeWindows() Close all the GraphWindows being displayed.
boolean	createFile(java.lang.String filename) Create a GraphWindow file.
void	exit()
boolean	match(ElVisSource source)
boolean	matchExact(ElVisSource source)
void	read(java.io.DataInputStream in)
boolean	register() Register the application with ElVis on the local computer and the default port.
boolean	register(java.lang.String name, java.lang.String port) Register the application with ElVis.
void	sendData(java.lang.String host, int port, byte[] b)
void	write(GraphWindow gw)

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_PORT

public static final int DEFAULT_PORT

See Also:

Constant Field Values

Constructor Detail

DataSource

public DataSource()

DataSource

public DataSource(java.lang.String sourceName,
                  java.lang.String inUser,
                  java.lang.String inID)

Define the application that will send data to ElVis.

Parameters:

sourceName - - The name of the application.

inUser - - The name of user running the application.

inID - - A text string for identifying an aspect or password of the run of the application.

Method Detail

register

public boolean register()

Register the application with ElVis on the local computer and the default port. Use the Java system property elvis.host as the computer running ElVis. If elvis.host is not defined then use the local computer. Use the Java system property elvis.port. If elvis.port is not defined then use the default port.

register

public boolean register(java.lang.String name,
                        java.lang.String port)

Register the application with ElVis.

Parameters:

name - - The name of the computer running ElVis. If name is null then use the Java system property elvis.host as the computer running ElVis. If elvis.host is not defined then use the local computer.

port - - The "well-known" port number reserved for connecting to ElVis. If port is null then use the Java system property elvis.port. If elvis.port is not defined then use the default port.

sendData

public void sendData(java.lang.String host,
                     int port,
                     byte[] b)

closeWindows

public void closeWindows()

Close all the GraphWindows being displayed.

write

public void write(GraphWindow gw)

createFile

public boolean createFile(java.lang.String filename)

Create a GraphWindow file. Used for data monitoring. Only 1 GraphWindow file is open at a time. This enables writing GraphWindows to a file instead of sending them to an ElVis display program. Create this DataSource. Then bracket all the calls to ElVis methods between calls to createFile and closeFile. For example:

                DataSource dataSource = new DataSource();
                boolean gwStatus = dataSource.createFile("sample.gw");

                boolean status = dataSource.register();

                drawGraph();	// calls to ElVis methods to create graphs.

                dataSource.closeFile();
 

Parameters:

filename - - The name of the file to create.

appendFile

public boolean appendFile(java.lang.String filename)

Append to a GraphWindow file. Used for data monitoring.

Parameters:

filename - - The name of the file to append.

closeFile

public boolean closeFile()

Close the currently open GraphWindow file.

closeFile

public boolean closeFile(boolean poll)

Close the currently open GraphWindow file and specify client polling.

read

public void read(java.io.DataInputStream in)

exit

public void exit()

match

public boolean match(ElVisSource source)

matchExact

public boolean matchExact(ElVisSource source)