import org.apache.jmeter.gui.GuiPackage;
import org.apache.commons.io.FilenameUtils;
import java.io.File;
import java.io.IOException;
String testPlanFileDir = FilenameUtils.getFullPathNoEndSeparator(GuiPackage.getInstance().getTestPlanFile());
testPlanFileDir = testPlanFileDir.replace("jmeter\\plans","target\\download");
File folder = new File(testPlanFileDir);
if(!folder.exists()){
folder.mkdirs();
}