RESOLVED - BATCH-414: consistent handling of empty input by ItemReaders

added StepListener that detects itemCount == 0 and throws exception

spring-batch-core/src/main/java/org/springframework/batch/core/step/NoItemsProcessedDetector.java

@@ -0,0 +1,43 @@
+/*
+ * Copyright 2002-2007 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.batch.core.step;
+
+import org.springframework.batch.core.StepExecution;
+import org.springframework.batch.core.listener.StepExecutionListenerSupport;
+import org.springframework.batch.repeat.ExitStatus;
+
+/**
+ * Fails the step if no items have been processed ( item count is 0).
+ * 
+ * @author Robert Kasanicky
+ */
+public class NoItemsProcessedDetector extends StepExecutionListenerSupport {
+
+	public ExitStatus afterStep(StepExecution stepExecution) {
+		if (stepExecution.getItemCount().intValue() == 0) {
+			throw new NoItemsProcessedException("Step has not processed any items");
+		}
+		return stepExecution.getExitStatus();
+	}
+
+	private static class NoItemsProcessedException extends RuntimeException {
+		public NoItemsProcessedException(String message) {
+			super(message);
+		}
+	}
+
+}