gda.device.scannable.StringPVConditionMonitor.java Source code

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Here is the source code for gda.device.scannable.StringPVConditionMonitor.java

Source

/*-
 * Copyright  2014 Diamond Light Source Ltd.
 *
 * This file is part of GDA.
 *
 * GDA is free software: you can redistribute it and/or modify it under the
 * terms of the GNU General Public License version 3 as published by the Free
 * Software Foundation.
 *
 * GDA is distributed in the hope that it will be useful, but WITHOUT ANY
 * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
 * details.
 *
 * You should have received a copy of the GNU General Public License along
 * with GDA. If not, see <http://www.gnu.org/licenses/>.
 */

package gda.device.scannable;

import org.apache.commons.lang.ArrayUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import gda.device.DeviceException;

/**
 * A zero-input, zero-output Scannable which when used in a scan will pause the scan if a given PV does not match one member of a given array of Strings.
 * <p>
 * E.g. this will pause a scan if a shutter PV is not "open".
 */
public class StringPVConditionMonitor extends PVConditionMonitorBase {

    private static final Logger logger = LoggerFactory.getLogger(StringPVConditionMonitor.class);

    String[] okStrings; // strings which mean beam is on target

    @Override
    protected void testShouldPause() throws DeviceException {
        if (!isConnected()) {
            logger.error("Epics channels not connected.");
        }

        if (!machineIsRunning()) {
            return;
        }

        while (!beamOnTarget()) {
            try {
                sendAndPrintMessage("Port shutter closed : pausing until it is opened");
                Thread.sleep(60000);
            } catch (InterruptedException e) {
                // someone trying to kill the thread so re-throw to kill any scan
                throw new DeviceException(e.getMessage(), e);
            }
        }

    }

    private boolean beamOnTarget() {
        try {
            String value = controller.cagetString(theChannel);
            return ArrayUtils.contains(okStrings, value);
        } catch (Exception e) {
            logger.error(e.getMessage(), e);
            return true;
        }
    }

    public String[] getOkStrings() {
        return okStrings;
    }

    public void setOkStrings(String[] okStrings) {
        this.okStrings = okStrings;
    }

}