From be7cea1603b26ab6b9e51fd6c4cf4c34e560effb Mon Sep 17 00:00:00 2001
From: dsyer <dsyer@2e8e966d-6415-0410-94b9-dc4e65435d03>
Date: Fri, 11 Sep 2009 09:38:25 +0000
Subject: [PATCH] RESOLVED - issue BATCH-1399: Expose StepExecutionAggregator
 as a strategy interface in PartitionStep

---
 .../DefaultStepExecutionAggregator.java       | 14 +++++++++-----
 .../support/StepExecutionAggregator.java      | 19 ++++++++++---------
 2 files changed, 19 insertions(+), 14 deletions(-)

diff --git a/spring-batch-core/src/main/java/org/springframework/batch/core/partition/support/DefaultStepExecutionAggregator.java b/spring-batch-core/src/main/java/org/springframework/batch/core/partition/support/DefaultStepExecutionAggregator.java
index b2bf2ad52..e1328dd62 100644
--- a/spring-batch-core/src/main/java/org/springframework/batch/core/partition/support/DefaultStepExecutionAggregator.java
+++ b/spring-batch-core/src/main/java/org/springframework/batch/core/partition/support/DefaultStepExecutionAggregator.java
@@ -19,6 +19,7 @@ package org.springframework.batch.core.partition.support;
 import java.util.Collection;
 
 import org.springframework.batch.core.BatchStatus;
+import org.springframework.batch.core.ExitStatus;
 import org.springframework.batch.core.StepExecution;
 import org.springframework.util.Assert;
 
@@ -32,11 +33,14 @@ import org.springframework.util.Assert;
 public class DefaultStepExecutionAggregator implements StepExecutionAggregator {
 
 	/**
-	 * Aggregates the status and exit status using their built in combination
-	 * rules (i.e. {@link BatchStatus#max(BatchStatus, BatchStatus) max} and
-	 * {@link ExitStatus#and(ExitStatus) and} respectively), and the counters by
-	 * simple arithmetic.
-	 * 
+	 * Aggregates the input executions into the result {@link StepExecution}.
+	 * The aggregated fields are
+	 * <ul>
+	 * <li>status - choosing the highest value using
+	 * {@link BatchStatus#max(BatchStatus, BatchStatus)}</li>
+	 * <li>exitStatus - using {@link ExitStatus#and(ExitStatus)}</li>
+	 * <li>commitCount, rollbackCount, etc. - by arithmetic sum</li>
+	 * </ul>
 	 * @see StepExecutionAggregator #aggregate(StepExecution, Collection)
 	 */
 	public void aggregate(StepExecution result, Collection<StepExecution> executions) {
diff --git a/spring-batch-core/src/main/java/org/springframework/batch/core/partition/support/StepExecutionAggregator.java b/spring-batch-core/src/main/java/org/springframework/batch/core/partition/support/StepExecutionAggregator.java
index 4b5c1692a..570ce5879 100644
--- a/spring-batch-core/src/main/java/org/springframework/batch/core/partition/support/StepExecutionAggregator.java
+++ b/spring-batch-core/src/main/java/org/springframework/batch/core/partition/support/StepExecutionAggregator.java
@@ -2,20 +2,21 @@ package org.springframework.batch.core.partition.support;
 
 import java.util.Collection;
 
-import org.springframework.batch.core.BatchStatus;
-import org.springframework.batch.core.ExitStatus;
 import org.springframework.batch.core.StepExecution;
 
+/**
+ * Strategy for a aggregating step executions, usually when they are the result
+ * of partitioned or remote execution.
+ * 
+ * @author Dave Syer
+ * 
+ * @since 2.1
+ * 
+ */
 public interface StepExecutionAggregator {
 
 	/**
-	 * Take the inputs and aggregate certain fields, putting the aggregates into
-	 * the result.  The aggregated fields are
-	 * <ul>
-	 * <li>status - choosing the highest value using {@link BatchStatus#max(BatchStatus, BatchStatus)}</li>
-	 * <li>exitStatus - using {@link ExitStatus#and(ExitStatus)}</li>
-	 * <li>commitCount, rollbackCount, etc. - by arithmetic sum</li>
-	 * </ul>
+	 * Take the inputs and aggregate, putting the aggregates into the result.
 	 * 
 	 * @param result the result to overwrite
 	 * @param executions the inputs