relaxed unnecessarily restrictive type parameters

spring-batch-infrastructure/src/main/java/org/springframework/batch/item/file/FlatFileItemReader.java

@@ -83,7 +83,7 @@ public class FlatFileItemReader<T> extends AbstractBufferedItemReaderItemStream<
 
 	private LineTokenizer tokenizer = new DelimitedLineTokenizer();
 
-	private FieldSetMapper<T> fieldSetMapper;
+	private FieldSetMapper<? extends T> fieldSetMapper;
 
 	/**
 	 * Encapsulates the state of the input source. If it is null then we are
@@ -186,7 +186,7 @@ public class FlatFileItemReader<T> extends AbstractBufferedItemReaderItemStream<
 	 * 
 	 * @param fieldSetMapper
 	 */
-	public void setFieldSetMapper(FieldSetMapper<T> fieldSetMapper) {
+	public void setFieldSetMapper(FieldSetMapper<? extends T> fieldSetMapper) {
 		this.fieldSetMapper = fieldSetMapper;
 	}
 

spring-batch-infrastructure/src/main/java/org/springframework/batch/item/file/FlatFileItemWriter.java

@@ -82,7 +82,7 @@ public class FlatFileItemWriter<T> extends ExecutionContextUserSupport implement
 
 	private LineAggregator lineAggregator = new DelimitedLineAggregator();
 
-	private FieldSetCreator<T> fieldSetCreator;
+	private FieldSetCreator<? super T> fieldSetCreator;
 
 	private boolean saveState = true;
 
@@ -137,7 +137,7 @@ public class FlatFileItemWriter<T> extends ExecutionContextUserSupport implement
 	 * 
 	 * @param fieldSetCreator the {@link FieldSetCreator} to set
 	 */
-	public void setFieldSetCreator(FieldSetCreator<T> fieldSetCreator) {
+	public void setFieldSetCreator(FieldSetCreator<? super T> fieldSetCreator) {
 		this.fieldSetCreator = fieldSetCreator;
 	}
 

spring-batch-infrastructure/src/main/java/org/springframework/batch/item/xml/StaxEventItemReader.java

@@ -37,7 +37,7 @@ public class StaxEventItemReader<T> extends AbstractBufferedItemReaderItemStream
 
 	private XMLEventReader eventReader;
 
-	private EventReaderDeserializer<T> eventReaderDeserializer;
+	private EventReaderDeserializer<? extends T> eventReaderDeserializer;
 
 	private Resource resource;
 
@@ -57,7 +57,7 @@ public class StaxEventItemReader<T> extends AbstractBufferedItemReaderItemStream
 	 * @param eventReaderDeserializer maps xml fragments corresponding to
 	 * records to objects
 	 */
-	public void setFragmentDeserializer(EventReaderDeserializer<T> eventReaderDeserializer) {
+	public void setFragmentDeserializer(EventReaderDeserializer<? extends T> eventReaderDeserializer) {
 		this.eventReaderDeserializer = eventReaderDeserializer;
 	}
 

spring-batch-infrastructure/src/main/java/org/springframework/batch/item/xml/StaxEventItemWriter.java

@@ -69,7 +69,7 @@ public class StaxEventItemWriter<T> extends ExecutionContextUserSupport implemen
 	private Resource resource;
 
 	// xml serializer
-	private EventWriterSerializer<T> serializer;
+	private EventWriterSerializer<? super T> serializer;
 
 	// encoding to be used while reading from the resource
 	private String encoding = DEFAULT_ENCODING;
@@ -135,7 +135,7 @@ public class StaxEventItemWriter<T> extends ExecutionContextUserSupport implemen
 	 * 
 	 * @param serializer the Object to XML serializer
 	 */
-	public void setSerializer(EventWriterSerializer<T> serializer) {
+	public void setSerializer(EventWriterSerializer<? super T> serializer) {
 		this.serializer = serializer;
 	}