dk.opi.io
Interface IOServer2

All Superinterfaces:

IOServer

All Known Implementing Classes:

OpcClientApi

public interface IOServer2

extends IOServer

An interface extending the IOServer interface with additional functionality

Method Summary

boolean

writeMultipleItems(Vector itemWriteList) Used for bulk write of one or more IOItem objects.

Methods inherited from interface dk.opi.io.IOServer

getGroups, releaseConnection, releaseConnection, removeGroup

Method Detail

writeMultipleItems

public boolean writeMultipleItems(Vector itemWriteList)
                           throws RbxIOException

Used for bulk write of one or more IOItem objects. Use this method to improve write performance when writing to many items at the same time. All the items are sent to the server as a single package, thus possible minimizing network bandwidth.

The method runs to completion. The values are written to the DEVICE. That is, the method will not return until it verifies that the device has actually accepted (or rejected) the data.

Writes are not affected by the ACTIVE state of the item.

Example of usage:

 import java.util.Vector;
 import dk.opi.io.*;
 import dk.opi.io.opc.opcclient.*;
 
 IOServer2 is;
 
 IOItem intItem;
 IOItem boolItem;
 IOItem stringItem;
 
 Vector witems = new Vector();
 witems.addElement(new IOItemWriteValue(intItem, new Integer(22)));
 witems.addElement(new IOItemWriteValue(boolItem, Boolean.TRUE));
 witems.addElement(new IOItemWriteValue(stringItem, "test string"));
 
 if (is.writeMultipleItems(witems)) {
   // one or more items not written - check the error
   for (int j = 0; j < witems.size(); j++) {
     IOItemWriteValue wVal = (IOItemWriteValue )witems.elementAt(j);
     String errText = wVal.getErrorText();
     if (errText != null) {
       System.out.println("errorText item no." + j +
                          " errorText=" + errText);
     } // end of if ()
   } // end of for (int  = 0;  < ; ++)
 } // end of if ()
 

Parameters:

itemWriteList - a Vector holding IOItemWriteValue objects. If an element in itemWriteList is not of this type, an exception will be thrown

Returns:

true if one or more items were not succesfully written to the the server. In that event the caller should check the itemWriteList Vector querying the IOItemWriteValue.getErrorText() method for the error description. In case false is returned all items were sucessfully written, so the user need not query the itemWriteList Vector.

Throws:

RbxIOException - if an write failure occured or if the size of the items and values Vectors are not the same.