Java tutorial
/********************************************************************** ** ** ** This code belongs to the KETTLE project. ** ** ** ** Kettle, from version 2.2 on, is released into the public domain ** ** under the Lesser GNU Public License (LGPL). ** ** ** ** For more details, please read the document LICENSE.txt, included ** ** in this project ** ** ** ** http://www.kettle.be ** ** info@kettle.be ** ** ** **********************************************************************/ package be.ibridge.kettle.job.entry.waitforfile; import java.io.IOException; import java.util.ArrayList; import org.apache.commons.vfs.FileObject; import org.eclipse.swt.widgets.Shell; import org.w3c.dom.Node; import be.ibridge.kettle.core.Const; import be.ibridge.kettle.core.LogWriter; import be.ibridge.kettle.core.Result; import be.ibridge.kettle.core.XMLHandler; import be.ibridge.kettle.core.exception.KettleDatabaseException; import be.ibridge.kettle.core.exception.KettleException; import be.ibridge.kettle.core.exception.KettleXMLException; import be.ibridge.kettle.core.util.StringUtil; import be.ibridge.kettle.core.vfs.KettleVFS; import be.ibridge.kettle.job.Job; import be.ibridge.kettle.job.JobMeta; import be.ibridge.kettle.job.entry.JobEntryBase; import be.ibridge.kettle.job.entry.JobEntryDialogInterface; import be.ibridge.kettle.job.entry.JobEntryInterface; import be.ibridge.kettle.repository.Repository; /** * This defines a 'wait for file' job entry. Its use is to wait for a file to * appear. * * @author Sven Boden * @since 10-02-2007 * */ public class JobEntryWaitForFile extends JobEntryBase implements Cloneable, JobEntryInterface { private String filename; private String maximumTimeout; // maximum timeout in seconds private String checkCycleTime; // cycle time in seconds private boolean successOnTimeout; private boolean fileSizeCheck; static private String DEFAULT_MAXIMUM_TIMEOUT = "0"; // infinite timeout static private String DEFAULT_CHECK_CYCLE_TIME = "60"; // 1 minute public JobEntryWaitForFile(String n) { super(n, ""); filename = null; maximumTimeout = DEFAULT_MAXIMUM_TIMEOUT; checkCycleTime = DEFAULT_CHECK_CYCLE_TIME; successOnTimeout = false; fileSizeCheck = false; setID(-1L); setType(JobEntryInterface.TYPE_JOBENTRY_WAIT_FOR_FILE); } public JobEntryWaitForFile() { this(""); } public JobEntryWaitForFile(JobEntryBase jeb) { super(jeb); } public Object clone() { JobEntryWaitForFile je = (JobEntryWaitForFile) super.clone(); return je; } public String getXML() { StringBuffer retval = new StringBuffer(50); retval.append(super.getXML()); retval.append(" ").append(XMLHandler.addTagValue("filename", filename)); retval.append(" ").append(XMLHandler.addTagValue("maximum_timeout", maximumTimeout)); retval.append(" ").append(XMLHandler.addTagValue("check_cycle_time", checkCycleTime)); retval.append(" ").append(XMLHandler.addTagValue("success_on_timeout", successOnTimeout)); retval.append(" ").append(XMLHandler.addTagValue("file_size_check", fileSizeCheck)); return retval.toString(); } public void loadXML(Node entrynode, ArrayList databases, Repository rep) throws KettleXMLException { try { super.loadXML(entrynode, databases); filename = XMLHandler.getTagValue(entrynode, "filename"); maximumTimeout = XMLHandler.getTagValue(entrynode, "maximum_timeout"); checkCycleTime = XMLHandler.getTagValue(entrynode, "check_cycle_time"); successOnTimeout = "Y".equalsIgnoreCase(XMLHandler.getTagValue(entrynode, "success_on_timeout")); fileSizeCheck = "Y".equalsIgnoreCase(XMLHandler.getTagValue(entrynode, "file_size_check")); } catch (KettleXMLException xe) { throw new KettleXMLException("Unable to load job entry of type 'wait for file' from XML node", xe); } } public void loadRep(Repository rep, long id_jobentry, ArrayList databases) throws KettleException { try { super.loadRep(rep, id_jobentry, databases); filename = rep.getJobEntryAttributeString(id_jobentry, "filename"); maximumTimeout = rep.getJobEntryAttributeString(id_jobentry, "maximum_timeout"); checkCycleTime = rep.getJobEntryAttributeString(id_jobentry, "check_cycle_time"); successOnTimeout = rep.getJobEntryAttributeBoolean(id_jobentry, "success_on_timeout"); fileSizeCheck = rep.getJobEntryAttributeBoolean(id_jobentry, "file_size_check"); } catch (KettleException dbe) { throw new KettleException( "Unable to load job entry of type 'wait for file' from the repository for id_jobentry=" + id_jobentry, dbe); } } public void saveRep(Repository rep, long id_job) throws KettleException { try { super.saveRep(rep, id_job); rep.saveJobEntryAttribute(id_job, getID(), "filename", filename); rep.saveJobEntryAttribute(id_job, getID(), "maximum_timeout", maximumTimeout); rep.saveJobEntryAttribute(id_job, getID(), "check_cycle_time", checkCycleTime); rep.saveJobEntryAttribute(id_job, getID(), "success_on_timeout", successOnTimeout); rep.saveJobEntryAttribute(id_job, getID(), "file_size_check", fileSizeCheck); } catch (KettleDatabaseException dbe) { throw new KettleException( "Unable to save job entry of type 'wait for file' to the repository for id_job=" + id_job, dbe); } } public void setFilename(String filename) { this.filename = filename; } public String getFilename() { return filename; } public String getRealFilename() { return StringUtil.environmentSubstitute(getFilename()); } public Result execute(Result prev_result, int nr, Repository rep, Job parentJob) { LogWriter log = LogWriter.getInstance(); Result result = new Result(nr); result.setResult(false); // starttime (in seconds) long timeStart = System.currentTimeMillis() / 1000; if (filename != null) { String realFilename = getRealFilename(); try { FileObject fileObject = null; fileObject = KettleVFS.getFileObject(realFilename); long iMaximumTimeout = Const.toInt(getMaximumTimeout(), Const.toInt(DEFAULT_MAXIMUM_TIMEOUT, 0)); long iCycleTime = Const.toInt(getCheckCycleTime(), Const.toInt(DEFAULT_CHECK_CYCLE_TIME, 0)); // // Sanity check on some values, and complain on insanity // if (iMaximumTimeout < 0) { iMaximumTimeout = Const.toInt(DEFAULT_MAXIMUM_TIMEOUT, 0); log.logBasic(toString(), "Maximum timeout invalid, reset to " + iMaximumTimeout); } if (iCycleTime < 1) { // If lower than 1 set to the default iCycleTime = Const.toInt(DEFAULT_CHECK_CYCLE_TIME, 1); log.logBasic(toString(), "Check cycle time invalid, reset to " + iCycleTime); } if (iMaximumTimeout == 0) { log.logBasic(toString(), "Waiting indefinitely for file [" + realFilename + "]"); } else { log.logBasic(toString(), "Waiting " + iMaximumTimeout + " seconds for file [" + realFilename + "]"); } boolean continueLoop = true; while (continueLoop && !parentJob.isStopped()) { if (fileObject.exists()) { // file exists, we're happy to exit log.logBasic(toString(), "Detected file [" + realFilename + "] within timeout"); result.setResult(true); continueLoop = false; } else { long now = System.currentTimeMillis() / 1000; if ((iMaximumTimeout > 0) && (now > (timeStart + iMaximumTimeout))) { continueLoop = false; // file doesn't exist after timeout, either true or false if (isSuccessOnTimeout()) { log.logBasic(toString(), "Didn't detect file [" + realFilename + "] before timeout, success"); result.setResult(true); } else { log.logBasic(toString(), "Didn't detect file [" + realFilename + "] before timeout, failure"); result.setResult(false); } } // sleep algorithm long sleepTime = 0; if (iMaximumTimeout == 0) { sleepTime = iCycleTime; } else { if ((now + iCycleTime) < (timeStart + iMaximumTimeout)) { sleepTime = iCycleTime; } else { sleepTime = iCycleTime - ((now + iCycleTime) - (timeStart + iMaximumTimeout)); } } try { if (sleepTime > 0) { if (log.isDetailed()) { log.logDetailed(toString(), "Sleeping " + sleepTime + " seconds before next check for file [" + realFilename + "]"); } Thread.sleep(sleepTime * 1000); } } catch (InterruptedException e) { // something strange happened result.setResult(false); continueLoop = false; } } } if (!parentJob.isStopped() && fileObject.exists() && isFileSizeCheck()) { long oldSize = -1; long newSize = fileObject.getContent().getSize(); log.logDetailed(toString(), "File [" + realFilename + "] is " + newSize + " bytes long"); log.logBasic(toString(), "Waiting until file [" + realFilename + "] stops growing for " + iCycleTime + " seconds"); while (oldSize != newSize && !parentJob.isStopped()) { try { if (log.isDetailed()) { log.logDetailed(toString(), "Sleeping " + iCycleTime + " seconds, waiting for file [" + realFilename + "] to stop growing"); } Thread.sleep(iCycleTime * 1000); } catch (InterruptedException e) { // something strange happened result.setResult(false); continueLoop = false; } oldSize = newSize; newSize = fileObject.getContent().getSize(); if (log.isDetailed()) { log.logDetailed(toString(), "File [" + realFilename + "] is " + newSize + " bytes long"); } } log.logBasic(toString(), "Stopped waiting for file [" + realFilename + "] to stop growing"); } if (parentJob.isStopped()) { result.setResult(false); } } catch (IOException e) { log.logBasic(toString(), "Exception while waiting for file [" + realFilename + "] to stop growing: " + e.getMessage()); } } else { log.logError(toString(), "No filename is defined."); } return result; } public boolean evaluates() { return true; } public JobEntryDialogInterface getDialog(Shell shell, JobEntryInterface jei, JobMeta jobMeta, String jobName, Repository rep) { return new JobEntryWaitForFileDialog(shell, this, jobMeta); } public boolean isSuccessOnTimeout() { return successOnTimeout; } public void setSuccessOnTimeout(boolean successOnTimeout) { this.successOnTimeout = successOnTimeout; } public String getCheckCycleTime() { return checkCycleTime; } public void setCheckCycleTime(String checkCycleTime) { this.checkCycleTime = checkCycleTime; } public String getMaximumTimeout() { return maximumTimeout; } public void setMaximumTimeout(String maximumTimeout) { this.maximumTimeout = maximumTimeout; } public boolean isFileSizeCheck() { return fileSizeCheck; } public void setFileSizeCheck(boolean fileSizeCheck) { this.fileSizeCheck = fileSizeCheck; } }