RESOLVED - issue BATCH-473: Create Tasklet sample job.

http://jira.springframework.org/browse/BATCH-473

added tasklet job that deletes files in given directory (description clarifies this would typically be a preliminary step in multi-step job)

spring-batch-samples/src/main/java/org/springframework/batch/sample/tasklet/FileDeletingTasklet.java

@@ -0,0 +1,44 @@
+package org.springframework.batch.sample.tasklet;
+
+import java.io.File;
+
+import org.springframework.batch.core.UnexpectedJobExecutionException;
+import org.springframework.batch.core.step.tasklet.Tasklet;
+import org.springframework.batch.repeat.ExitStatus;
+import org.springframework.beans.factory.InitializingBean;
+import org.springframework.core.io.Resource;
+import org.springframework.util.Assert;
+
+/**
+ * Deletes files in given directory. Ignores subdirectories. Fails (by throwing
+ * exception) if any of the files could not be deleted.
+ * 
+ * @author Robert Kasanicky
+ */
+public class FileDeletingTasklet implements Tasklet, InitializingBean {
+
+	private Resource directory;
+
+	public ExitStatus execute() throws Exception {
+		File dir = directory.getFile();
+		Assert.state(dir.isDirectory());
+
+		File[] files = dir.listFiles();
+		for (int i = 0; i < files.length; i++) {
+			boolean deleted = files[i].delete();
+			if (!deleted) {
+				throw new UnexpectedJobExecutionException("Could not delete file " + files[i].getPath());
+			}
+		}
+		return ExitStatus.FINISHED;
+	}
+
+	public void setDirectoryResource(Resource directory) {
+		this.directory = directory;
+	}
+
+	public void afterPropertiesSet() throws Exception {
+		Assert.notNull(directory, "directory must be set");
+	}
+
+}