Fix tests failing on Windows

Before this commit, tests in this change set
were failing on MS Windows due to the file
comparison method which was based on file
content hash comparison. With this method,
differences between OS line endings
(LF vs CRLF) in generated json files produce
different hashes.

This commit uses a logical json comparison
based on the jsonassert library.

spring-batch-infrastructure/src/test/java/org/springframework/batch/item/json/GsonJsonFileItemWriterFunctionalTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2018 the original author or authors.
+ * Copyright 2018-2021 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.
@@ -44,4 +44,9 @@ public class GsonJsonFileItemWriterFunctionalTests extends JsonFileItemWriterFun
 		return "expected-trades-gson-pretty-print.json";
 	}
 
+	@Override
+	protected String getMarshallerName() {
+		return "gson";
+	}
+
 }

spring-batch-infrastructure/src/test/java/org/springframework/batch/item/json/JacksonJsonFileItemWriterFunctionalTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2018 the original author or authors.
+ * Copyright 2018-2021 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.
@@ -45,4 +45,9 @@ public class JacksonJsonFileItemWriterFunctionalTests extends JsonFileItemWriter
 		return "expected-trades-jackson-pretty-print.json";
 	}
 
+	@Override
+	protected String getMarshallerName() {
+		return "jackson";
+	}
+
 }

spring-batch-infrastructure/src/test/java/org/springframework/batch/item/json/JsonFileItemWriterFunctionalTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2018 the original author or authors.
+ * Copyright 2018-2021 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.
@@ -18,7 +18,9 @@ package org.springframework.batch.item.json;
 
 import java.io.File;
 import java.io.FileInputStream;
+import java.io.IOException;
 import java.math.BigDecimal;
+import java.nio.charset.Charset;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.Paths;
@@ -29,6 +31,7 @@ import java.util.List;
 import org.junit.Assert;
 import org.junit.Before;
 import org.junit.Test;
+import org.skyscreamer.jsonassert.JSONAssert;
 
 import org.springframework.batch.item.ExecutionContext;
 import org.springframework.batch.item.UnexpectedInputException;
@@ -54,9 +57,6 @@ public abstract class JsonFileItemWriterFunctionalTests {
 
 	private static final String EXPECTED_FILE_DIRECTORY = "src/test/resources/org/springframework/batch/item/json/";
 
-	private Resource resource;
-	private List<Trade> items;
-	private ExecutionContext executionContext;
 	private Trade trade1 = new Trade("123", 5, new BigDecimal("10.5"), "foo");
 	private Trade trade2 = new Trade("456", 10, new BigDecimal("20.5"), "bar");
 	private Trade trade3 = new Trade("789", 15, new BigDecimal("30.5"), "foobar");
@@ -65,217 +65,274 @@ public abstract class JsonFileItemWriterFunctionalTests {
 	protected abstract JsonObjectMarshaller<Trade> getJsonObjectMarshaller();
 	protected abstract JsonObjectMarshaller<Trade> getJsonObjectMarshallerWithPrettyPrint();
 	protected abstract String getExpectedPrettyPrintedFile();
-
-	private JsonFileItemWriter<Trade> writer;
-
-	@Before
-	public void setUp() throws Exception {
-		Path outputFilePath = Paths.get("target", "trades.json");
-		Files.deleteIfExists(outputFilePath);
-		this.resource = new FileSystemResource(outputFilePath.toFile());
-		this.executionContext = new ExecutionContext();
-		this.items = Arrays.asList(this.trade1, this.trade2);
-		this.writer = new JsonFileItemWriterBuilder<Trade>()
-				.name("tradesItemWriter")
-				.resource(this.resource)
-				.jsonObjectMarshaller(getJsonObjectMarshaller())
-				.build();
-	}
+	protected abstract String getMarshallerName();
 
 	@Test
 	public void testJsonWriting() throws Exception {
+		//given
+		Path outputFilePath = Paths.get("target", "trades-" + getMarshallerName() + ".json");
+		FileSystemResource resource = new FileSystemResource(outputFilePath);
+		JsonFileItemWriter<Trade> writer = new JsonFileItemWriterBuilder<Trade>()
+				.name("tradesItemWriter")
+				.resource(resource)
+				.jsonObjectMarshaller(getJsonObjectMarshaller())
+				.build();
+
 		// when
-		this.writer.open(this.executionContext);
-		this.writer.write(this.items);
-		this.writer.close();
+		writer.open(new ExecutionContext());
+		writer.write(Arrays.asList(this.trade1, this.trade2));
+		writer.close();
 
 		// then
 		assertFileEquals(
 				new File(EXPECTED_FILE_DIRECTORY + "expected-trades.json"),
-				this.resource.getFile());
+				resource.getFile());
 	}
 
 	@Test
 	public void testJsonWritingWithMultipleWrite() throws Exception {
+		//given
+		Path outputFilePath = Paths.get("target", "testJsonWritingWithMultipleWrite-" + getMarshallerName() + ".json");
+		FileSystemResource resource = new FileSystemResource(outputFilePath);
+		JsonFileItemWriter<Trade> writer = new JsonFileItemWriterBuilder<Trade>()
+				.name("tradesItemWriter")
+				.resource(resource)
+				.jsonObjectMarshaller(getJsonObjectMarshaller())
+				.build();
+
 		// when
-		this.writer.open(this.executionContext);
-		this.writer.write(this.items);
-		this.writer.write(Arrays.asList(trade3, trade4));
-		this.writer.close();
+		writer.open(new ExecutionContext());
+		writer.write(Arrays.asList(this.trade1, this.trade2));
+		writer.write(Arrays.asList(this.trade3, this.trade4));
+		writer.close();
 
 		// then
 		assertFileEquals(
 				new File(EXPECTED_FILE_DIRECTORY + "expected-trades-with-multiple-writes.json"),
-				this.resource.getFile());
+				resource.getFile());
 	}
 
 	@Test
 	public void testJsonWritingWithPrettyPrinting() throws Exception {
 		// given
-		this.writer = new JsonFileItemWriterBuilder<Trade>()
+		Path outputFilePath = Paths.get("target", "testJsonWritingWithPrettyPrinting-" + getMarshallerName() + ".json");
+		FileSystemResource resource = new FileSystemResource(outputFilePath);
+		JsonFileItemWriter<Trade> writer = new JsonFileItemWriterBuilder<Trade>()
 				.name("tradesItemWriter")
-				.resource(this.resource)
+				.resource(resource)
 				.jsonObjectMarshaller(getJsonObjectMarshallerWithPrettyPrint())
 				.build();
 
 		// when
-		this.writer.open(this.executionContext);
-		this.writer.write(this.items);
-		this.writer.close();
+		writer.open(new ExecutionContext());
+		writer.write(Arrays.asList(this.trade1, this.trade2));
+		writer.close();
 
 		// when
 		assertFileEquals(
 				new File(EXPECTED_FILE_DIRECTORY + getExpectedPrettyPrintedFile()),
-				this.resource.getFile());
+				resource.getFile());
 	}
 
 	@Test
 	public void testJsonWritingWithEnclosingObject() throws Exception {
 		// given
-		this.writer.setHeaderCallback(writer -> writer.write("{\"trades\":["));
-		this.writer.setFooterCallback(writer -> writer.write(JsonFileItemWriter.DEFAULT_LINE_SEPARATOR + "]}"));
+		Path outputFilePath = Paths.get("target", "testJsonWritingWithEnclosingObject-" + getMarshallerName() + ".json");
+		FileSystemResource resource = new FileSystemResource(outputFilePath);
+		JsonFileItemWriter<Trade> writer = new JsonFileItemWriterBuilder<Trade>()
+				.name("tradesItemWriter")
+				.resource(resource)
+				.jsonObjectMarshaller(getJsonObjectMarshaller())
+				.headerCallback(headerWriter -> headerWriter.write("{\"trades\":["))
+				.footerCallback(footerWriter -> footerWriter.write(JsonFileItemWriter.DEFAULT_LINE_SEPARATOR + "]}"))
+				.build();
 
 		// when
-		this.writer.open(this.executionContext);
-		this.writer.write(this.items);
-		this.writer.close();
+		writer.open(new ExecutionContext());
+		writer.write(Arrays.asList(this.trade1, this.trade2));
+		writer.close();
 
 		// then
 		assertFileEquals(
 				new File(EXPECTED_FILE_DIRECTORY + "expected-trades-with-wrapper-object.json"),
-				this.resource.getFile());
+				resource.getFile());
 	}
 
 	@Test
 	public void testForcedWrite() throws Exception {
 		// given
-		this.writer.setForceSync(true);
+		Path outputFilePath = Paths.get("target", "testForcedWrite-" + getMarshallerName() + ".json");
+		FileSystemResource resource = new FileSystemResource(outputFilePath);
+		JsonFileItemWriter<Trade> writer = new JsonFileItemWriterBuilder<Trade>()
+				.name("tradesItemWriter")
+				.resource(resource)
+				.jsonObjectMarshaller(getJsonObjectMarshaller())
+				.forceSync(true)
+				.build();
 
 		// when
-		this.writer.open(this.executionContext);
-		this.writer.write(Collections.singletonList(this.trade1));
-		this.writer.close();
+		writer.open(new ExecutionContext());
+		writer.write(Collections.singletonList(this.trade1));
+		writer.close();
 
 		// then
 		assertFileEquals(
 				new File(EXPECTED_FILE_DIRECTORY + "expected-trades1.json"),
-				this.resource.getFile());
+				resource.getFile());
 	}
 
 	@Test
 	public void testWriteWithDelete() throws Exception {
 		// given
-		this.writer.setShouldDeleteIfExists(true);
+		ExecutionContext executionContext = new ExecutionContext();
+		Path outputFilePath = Paths.get("target", "testWriteWithDelete-" + getMarshallerName() + ".json");
+		FileSystemResource resource = new FileSystemResource(outputFilePath);
+		JsonFileItemWriter<Trade> writer = new JsonFileItemWriterBuilder<Trade>()
+				.name("tradesItemWriter")
+				.resource(resource)
+				.jsonObjectMarshaller(getJsonObjectMarshaller())
+				.shouldDeleteIfExists(true)
+				.build();
 
 		// when
-		this.writer.open(this.executionContext);
-		this.writer.write(Collections.singletonList(this.trade1));
-		this.writer.close();
-		this.writer.open(this.executionContext);
-		this.writer.write(Collections.singletonList(this.trade2));
-		this.writer.close();
+		writer.open(executionContext);
+		writer.write(Collections.singletonList(this.trade1));
+		writer.close();
+		writer.open(executionContext);
+		writer.write(Collections.singletonList(this.trade2));
+		writer.close();
 
 		// then
 		assertFileEquals(
 				new File(EXPECTED_FILE_DIRECTORY + "expected-trades2.json"),
-				this.resource.getFile());
+				resource.getFile());
 	}
 
 	@Test
 	public void testRestart() throws Exception {
-		this.writer.open(this.executionContext);
+		// given
+		ExecutionContext executionContext = new ExecutionContext();
+		Path outputFilePath = Paths.get("target", "testRestart-" + getMarshallerName() + ".json");
+		FileSystemResource resource = new FileSystemResource(outputFilePath);
+		JsonFileItemWriter<Trade> writer = new JsonFileItemWriterBuilder<Trade>()
+				.name("tradesItemWriter")
+				.resource(resource)
+				.jsonObjectMarshaller(getJsonObjectMarshaller())
+				.build();
+
+		// when
+		writer.open(executionContext);
 		// write some lines
-		this.writer.write(Collections.singletonList(this.trade1));
+		writer.write(Collections.singletonList(this.trade1));
 		// get restart data
-		this.writer.update(this.executionContext);
+		writer.update(executionContext);
 		// close template
-		this.writer.close();
+		writer.close();
 
 		// init with correct data
-		this.writer.open(this.executionContext);
+		writer.open(executionContext);
 		// write more lines
-		this.writer.write(Collections.singletonList(this.trade2));
+		writer.write(Collections.singletonList(this.trade2));
 		// get statistics
-		this.writer.update(this.executionContext);
+		writer.update(executionContext);
 		// close template
-		this.writer.close();
+		writer.close();
 
 		// verify what was written to the file
 		assertFileEquals(
 				new File(EXPECTED_FILE_DIRECTORY+ "expected-trades.json"),
-				this.resource.getFile());
+				resource.getFile());
 
 		// 2 lines were written to the file in total
-		assertEquals(2, this.executionContext.getLong("tradesItemWriter.written"));
+		assertEquals(2, executionContext.getLong("tradesItemWriter.written"));
 	}
 
 	@Test
 	public void testTransactionalRestart() throws Exception {
-		this.writer.open(this.executionContext);
+		// given
 		PlatformTransactionManager transactionManager = new ResourcelessTransactionManager();
+		ExecutionContext executionContext = new ExecutionContext();
+		Path outputFilePath = Paths.get("target", "testTransactionalRestart-" + getMarshallerName() + ".json");
+		FileSystemResource resource = new FileSystemResource(outputFilePath);
+		JsonFileItemWriter<Trade> writer = new JsonFileItemWriterBuilder<Trade>()
+				.name("tradesItemWriter")
+				.resource(resource)
+				.jsonObjectMarshaller(getJsonObjectMarshaller())
+				.build();
+
+		// when
+		writer.open(executionContext);
 
 		new TransactionTemplate(transactionManager).execute((TransactionCallback<Void>) status -> {
 			try {
 				// write some lines
-				this.writer.write(Collections.singletonList(this.trade1));
+				writer.write(Collections.singletonList(this.trade1));
 			}
 			catch (Exception e) {
 				throw new UnexpectedInputException("Could not write data", e);
 			}
 			// get restart data
-			this.writer.update(this.executionContext);
+			writer.update(executionContext);
 			return null;
 		});
 		// close template
-		this.writer.close();
+		writer.close();
 
 		// init with correct data
-		this.writer.open(this.executionContext);
+		writer.open(executionContext);
 
 		new TransactionTemplate(transactionManager).execute((TransactionCallback<Void>) status -> {
 			try {
 				// write more lines
-				this.writer.write(Collections.singletonList(this.trade2));
+				writer.write(Collections.singletonList(this.trade2));
 			}
 			catch (Exception e) {
 				throw new UnexpectedInputException("Could not write data", e);
 			}
 			// get restart data
-			this.writer.update(this.executionContext);
+			writer.update(executionContext);
 			return null;
 		});
 		// close template
-		this.writer.close();
+		writer.close();
 
 		// verify what was written to the file
 		assertFileEquals(
 				new File(EXPECTED_FILE_DIRECTORY+ "expected-trades.json"),
-				this.resource.getFile());
+				resource.getFile());
 
 		// 2 lines were written to the file in total
-		assertEquals(2, this.executionContext.getLong("tradesItemWriter.written"));
+		assertEquals(2, executionContext.getLong("tradesItemWriter.written"));
 	}
 
 	@Test
 	public void testItemMarshallingFailure() throws Exception {
-		this.writer.setJsonObjectMarshaller(item -> {
-			throw new IllegalArgumentException("Bad item");
-		});
-		this.writer.open(this.executionContext);
+		// given
+		ExecutionContext executionContext = new ExecutionContext();
+		Path outputFilePath = Paths.get("target", "testItemMarshallingFailure-" + getMarshallerName() + ".json");
+		FileSystemResource resource = new FileSystemResource(outputFilePath);
+		JsonFileItemWriter<Trade> writer = new JsonFileItemWriterBuilder<Trade>()
+				.name("tradesItemWriter")
+				.resource(resource)
+				.jsonObjectMarshaller(item -> { throw new IllegalArgumentException("Bad item"); })
+				.build();
+
+		// when
+		writer.open(executionContext);
 		try {
-			this.writer.write(Collections.singletonList(this.trade1));
+			writer.write(Collections.singletonList(this.trade1));
 			fail();
 		}
 		catch (IllegalArgumentException iae) {
 			assertEquals("Bad item", iae.getMessage());
 		}
 		finally {
-			this.writer.close();
+			writer.close();
 		}
 
 		assertFileEquals(
 				new File(EXPECTED_FILE_DIRECTORY + "empty-trades.json"),
-				this.resource.getFile());
+				resource.getFile());
 	}
 
 	@Test
@@ -283,29 +340,35 @@ public abstract class JsonFileItemWriterFunctionalTests {
 	 * If append=true a new output file should still be created on the first run (not restart).
 	 */
 	public void testAppendToNotYetExistingFile() throws Exception {
-		Resource toBeCreated = new FileSystemResource("target/FlatFileItemWriterTests.out");
+		// given
+		ExecutionContext executionContext = new ExecutionContext();
+		Path outputFilePath = Paths.get("target", "testAppendToNotYetExistingFile-" + getMarshallerName() + ".json");
+		FileSystemResource resource = new FileSystemResource(outputFilePath);
+		Files.deleteIfExists(outputFilePath);
+		JsonFileItemWriter<Trade> writer = new JsonFileItemWriterBuilder<Trade>()
+				.name("tradesItemWriter")
+				.resource(new FileSystemResource(outputFilePath))
+				.jsonObjectMarshaller(getJsonObjectMarshaller())
+				.append(true)
+				.build();
 
-		File outputFile = toBeCreated.getFile(); //enable easy content reading and auto-delete the file
-
-		assertFalse("output file does not exist yet", toBeCreated.exists());
-		this.writer.setResource(toBeCreated);
-		this.writer.setAppendAllowed(true);
-		this.writer.afterPropertiesSet();
-
-		this.writer.open(this.executionContext);
-		assertTrue("output file was created", toBeCreated.exists());
-
-		this.writer.write(Collections.singletonList(this.trade1));
-		this.writer.close();
+		// when
+		writer.open(executionContext);
+		writer.write(Collections.singletonList(this.trade1));
+		writer.close();
+		
+		// then
 		assertFileEquals(
 				new File(EXPECTED_FILE_DIRECTORY + "expected-trades1.json"),
-				outputFile);
-		outputFile.delete();
+				resource.getFile());
 	}
 
 	private void assertFileEquals(File expected, File actual) throws Exception {
-		String expectedHash = DigestUtils.md5DigestAsHex(new FileInputStream(expected));
-		String actualHash = DigestUtils.md5DigestAsHex(new FileInputStream(actual));
-		Assert.assertEquals(expectedHash, actualHash);
+		JSONAssert.assertEquals(getContent(expected), getContent(actual), false);
 	}
+
+	private String getContent(File file) throws IOException {
+		return new String(Files.readAllBytes(file.toPath()), Charset.defaultCharset());
+	}
+
 }