IN PROGRESS - BATCH-863: introduce LineMapper interface to encapsulate string-to-item mapping

added RLR tests for restart with skipping lines and non-default recordSeparatorPolicy

spring-batch-infrastructure/src/test/java/org/springframework/batch/item/file/ResourceLineReaderTests.java

@@ -0,0 +1,101 @@
+package org.springframework.batch.item.file;
+
+import static org.junit.Assert.*;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.springframework.batch.item.ExecutionContext;
+import org.springframework.batch.item.file.mapping.PassThroughLineMapper;
+import org.springframework.batch.item.file.separator.RecordSeparatorPolicy;
+import org.springframework.core.io.ByteArrayResource;
+import org.springframework.core.io.Resource;
+import org.springframework.util.ClassUtils;
+
+/**
+ * Tests for {@link ResourceLineReader}.
+ */
+public class ResourceLineReaderTests {
+
+	private ResourceLineReader<String> reader = new ResourceLineReader<String>();
+
+	private ExecutionContext executionContext = new ExecutionContext();
+
+	@Before
+	public void setUp() {
+
+		reader.setResource(getInputResource("testLine1\ntestLine2\ntestLine3\ntestLine4\ntestLine5\ntestLine6"));
+		reader.setLineMapper(new PassThroughLineMapper());
+	}
+
+	@Test
+	public void testRestartWithCustomRecordSeparatorPolicy() throws Exception {
+
+		reader.setRecordSeparatorPolicy(new RecordSeparatorPolicy() {
+			// 1 record = 2 lines
+			boolean pair = true;
+
+			public boolean isEndOfRecord(String line) {
+				pair = !pair;
+				return pair;
+			}
+
+			public String postProcess(String record) {
+				return record;
+			}
+
+			public String preProcess(String record) {
+				return record;
+			}
+		});
+
+		reader.open(executionContext);
+
+		assertEquals("testLine1testLine2", reader.read().toString());
+		assertEquals("testLine3testLine4", reader.read().toString());
+
+		reader.update(executionContext);
+
+		reader.close(executionContext);
+
+		reader.open(executionContext);
+
+		assertEquals("testLine5testLine6", reader.read().toString());
+	}
+
+	@Test
+	public void testRestartWithSkippedLines() throws Exception {
+
+		reader.setLinesToSkip(2);
+		reader.open(executionContext);
+
+		// read some records
+		reader.read();
+		reader.read();
+		// get restart data
+		reader.update(executionContext);
+		// read next two records
+		reader.read();
+		reader.read();
+
+		assertEquals(2, executionContext.getLong(ClassUtils.getShortName(FlatFileItemReader.class) + ".read.count"));
+		// close input
+		reader.close(executionContext);
+
+		reader
+				.setResource(getInputResource("header\nignoreme\ntestLine1\ntestLine2\ntestLine3\ntestLine4\ntestLine5\ntestLine6"));
+
+		// init for restart
+		reader.open(executionContext);
+
+		// read remaining records
+		assertEquals("testLine3", reader.read().toString());
+		assertEquals("testLine4", reader.read().toString());
+
+		reader.update(executionContext);
+		assertEquals(4, executionContext.getLong(ClassUtils.getShortName(FlatFileItemReader.class) + ".read.count"));
+	}
+
+	private Resource getInputResource(String input) {
+		return new ByteArrayResource(input.getBytes());
+	}
+}