From 4e7c64a44344a53d49c5e9ecda2aa4f22c467fcf Mon Sep 17 00:00:00 2001
From: Mahmoud Ben Hassine <mbenhassine@pivotal.io>
Date: Thu, 9 May 2019 16:48:53 +0200
Subject: [PATCH] Add method to set a custom BufferedReaderFactory in
 FlatFileItemReaderBuilder

Resolves BATCH-2770
---
 .../builder/FlatFileItemReaderBuilder.java    | 22 ++++++++++++++++++-
 .../FlatFileItemReaderBuilderTests.java       |  6 ++++-
 2 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/spring-batch-infrastructure/src/main/java/org/springframework/batch/item/file/builder/FlatFileItemReaderBuilder.java b/spring-batch-infrastructure/src/main/java/org/springframework/batch/item/file/builder/FlatFileItemReaderBuilder.java
index b106cd6dc..9f43f685a 100644
--- a/spring-batch-infrastructure/src/main/java/org/springframework/batch/item/file/builder/FlatFileItemReaderBuilder.java
+++ b/spring-batch-infrastructure/src/main/java/org/springframework/batch/item/file/builder/FlatFileItemReaderBuilder.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2016-2018 the original author or authors.
+ * Copyright 2016-2019 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.
@@ -29,6 +29,8 @@ import java.util.Set;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 
+import org.springframework.batch.item.file.BufferedReaderFactory;
+import org.springframework.batch.item.file.DefaultBufferedReaderFactory;
 import org.springframework.batch.item.file.FlatFileItemReader;
 import org.springframework.batch.item.file.LineCallbackHandler;
 import org.springframework.batch.item.file.LineMapper;
@@ -69,6 +71,9 @@ public class FlatFileItemReaderBuilder<T> {
 	private RecordSeparatorPolicy recordSeparatorPolicy =
 			new SimpleRecordSeparatorPolicy();
 
+	private BufferedReaderFactory bufferedReaderFactory =
+			new DefaultBufferedReaderFactory();
+
 	private Resource resource;
 
 	private List<String> comments = new ArrayList<>();
@@ -201,6 +206,19 @@ public class FlatFileItemReaderBuilder<T> {
 		return this;
 	}
 
+	/**
+	 * Configure a custom {@link BufferedReaderFactory} for the reader.
+	 *
+	 * @param factory custom factory
+	 * @return The current instance of the builder.
+	 * @see FlatFileItemReader#setBufferedReaderFactory(BufferedReaderFactory)
+	 */
+	public FlatFileItemReaderBuilder<T> bufferedReaderFactory(BufferedReaderFactory factory) {
+		this.bufferedReaderFactory = factory;
+		return this;
+	}
+
+
 	/**
 	 * The {@link Resource} to be used as input.
 	 *
@@ -429,6 +447,7 @@ public class FlatFileItemReaderBuilder<T> {
 		}
 
 		Assert.notNull(this.recordSeparatorPolicy, "A RecordSeparatorPolicy is required.");
+		Assert.notNull(this.bufferedReaderFactory, "A BufferedReaderFactory is required.");
 		int validatorValue = this.tokenizerValidator.intValue();
 
 		FlatFileItemReader<T> reader = new FlatFileItemReader<>();
@@ -500,6 +519,7 @@ public class FlatFileItemReaderBuilder<T> {
 
 		reader.setSkippedLinesCallback(this.skippedLinesCallback);
 		reader.setRecordSeparatorPolicy(this.recordSeparatorPolicy);
+		reader.setBufferedReaderFactory(this.bufferedReaderFactory);
 		reader.setMaxItemCount(this.maxItemCount);
 		reader.setCurrentItemCount(this.currentItemCount);
 		reader.setSaveState(this.saveState);
diff --git a/spring-batch-infrastructure/src/test/java/org/springframework/batch/item/file/builder/FlatFileItemReaderBuilderTests.java b/spring-batch-infrastructure/src/test/java/org/springframework/batch/item/file/builder/FlatFileItemReaderBuilderTests.java
index abc110e1a..78e085664 100644
--- a/spring-batch-infrastructure/src/test/java/org/springframework/batch/item/file/builder/FlatFileItemReaderBuilderTests.java
+++ b/spring-batch-infrastructure/src/test/java/org/springframework/batch/item/file/builder/FlatFileItemReaderBuilderTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2016-2018 the original author or authors.
+ * Copyright 2016-2019 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.
@@ -15,6 +15,8 @@
  */
 package org.springframework.batch.item.file.builder;
 
+import java.io.InputStreamReader;
+import java.io.LineNumberReader;
 import java.util.ArrayList;
 import java.util.List;
 
@@ -174,6 +176,8 @@ public class FlatFileItemReaderBuilderTests {
 				.names("first", "second", "third")
 				.targetType(Foo.class)
 				.recordSeparatorPolicy(new DefaultRecordSeparatorPolicy("\"", "%"))
+				.bufferedReaderFactory((resource, encoding) ->
+						new LineNumberReader(new InputStreamReader(resource.getInputStream(), encoding)))
 				.maxItemCount(2)
 				.saveState(false)
 				.build();