Improved tests, added checks on output directory

org.springframework.integration.file/src/main/java/org/springframework/integration/file/FileWritingMessageHandler.java

@@ -32,15 +32,16 @@ import org.springframework.util.FileCopyUtils;
 /**
  * A {@link MessageHandler} implementation that writes the Message payload to a
  * file. If the payload is a File object, it will copy the File to this
- * consumer's directory. If the payload is a byte array or String, it will
- * write it directly. Otherwise, the payload type is unsupported, and an
- * Exception will be thrown.
+ * consumer's directory. If the payload is a byte array or String, it will write
+ * it directly. Otherwise, the payload type is unsupported, and an Exception
+ * will be thrown.
  * <p>
- * Other transformers may be useful to precede this handler. For example,
- * any Serializable object payload can be converted into a byte array by the
- * {@link org.springframework.integration.transformer.PayloadSerializingTransformer}.
- * Likewise, any Object can be converted to a String based on its <code>toString()</code>
- * method by the {@link org.springframework.integration.transformer.ObjectToStringTransformer}.
+ * Other transformers may be useful to precede this handler. For example, any
+ * Serializable object payload can be converted into a byte array by the
+ * {@link org.springframework.integration.transformer.PayloadSerializingTransformer}
+ * . Likewise, any Object can be converted to a String based on its
+ * <code>toString()</code> method by the
+ * {@link org.springframework.integration.transformer.ObjectToStringTransformer}.
  * 
  * @author Mark Fisher
  * @author Iwein Fuld
@@ -51,26 +52,27 @@ public class FileWritingMessageHandler implements MessageHandler {
 
 	private final File parentDirectory;
 
-	private volatile Charset charset = Charset.defaultCharset(); 
+	private volatile Charset charset = Charset.defaultCharset();
 
 	public FileWritingMessageHandler(Resource parentDirectory) {
 		try {
+			Assert.isTrue(parentDirectory.exists(), "Output directory [" + parentDirectory + "] does not exist");
 			this.parentDirectory = parentDirectory.getFile();
+			Assert.isTrue(this.parentDirectory.isDirectory(), "[" + this.parentDirectory + "] is not a directory");
+			Assert.isTrue(this.parentDirectory.canWrite(), "[" + this.parentDirectory + "] should be writable");			
 		}
 		catch (IOException e) {
-			// TODO Auto-generated catch block
-			throw new RuntimeException(e);
+			throw new IllegalArgumentException("Inaccessable output directory", e);
 		}
 	}
 
-
 	public void setFileNameGenerator(FileNameGenerator fileNameGenerator) {
 		this.fileNameGenerator = fileNameGenerator;
 	}
 
 	/**
-	 * Set the charset name to use when writing a File from a
-	 * String-based Message payload.
+	 * Set the charset name to use when writing a File from a String-based
+	 * Message payload.
 	 */
 	public void setCharset(String charset) {
 		Assert.notNull(charset, "charset must not be null");
@@ -95,8 +97,8 @@ public class FileWritingMessageHandler implements MessageHandler {
 				FileCopyUtils.copy((String) payload, writer);
 			}
 			else {
-				throw new IllegalArgumentException(
-						"unsupported Message payload type [" + payload.getClass().getName() + "]");
+				throw new IllegalArgumentException("unsupported Message payload type [" + payload.getClass().getName()
+						+ "]");
 			}
 		}
 		catch (Exception e) {

org.springframework.integration.file/src/test/java/org/springframework/integration/file/FileWritingMessageHandlerTests.java

@@ -17,8 +17,15 @@
 package org.springframework.integration.file;
 
 import static org.easymock.EasyMock.*;
+import static org.hamcrest.CoreMatchers.*;
+import static org.junit.Assert.assertThat;
+
 import java.io.File;
 
+import org.junit.After;
+import org.junit.AfterClass;
+import org.junit.Before;
+import org.junit.BeforeClass;
 import org.junit.Test;
 
 import org.springframework.core.io.Resource;
@@ -30,16 +37,50 @@ import org.springframework.integration.message.MessageHandlingException;
  * @author Iwein Fuld
  */
 public class FileWritingMessageHandlerTests {
-	
+
 	private Resource outputDirectory = createMock(Resource.class);
 
+	private FileWritingMessageHandler subject;
+
+	private static File outputDirectoryFile = new File(System.getProperty("java.io.tmpdir") + "/"
+			+ FileWritingMessageHandlerTests.class.getSimpleName());;
+
+	@BeforeClass
+	public static void setupOutputDir() throws Exception {
+		outputDirectoryFile.mkdir();
+	}
+
+
+	@Before
+	public void setup() throws Exception {
+		expect(outputDirectory.getFile()).andReturn(outputDirectoryFile).anyTimes();
+		expect(outputDirectory.exists()).andReturn(true).anyTimes();
+		replay(outputDirectory);
+		subject = new FileWritingMessageHandler(outputDirectory);
+	}
+
 	@Test(expected = MessageHandlingException.class)
 	public void unsupportedType() throws Exception {
-		expect(outputDirectory.getFile()).andReturn(new File(System.getProperty("java.io.tmpdir"))).anyTimes();
-		replay(outputDirectory);
-		FileWritingMessageHandler handler = new FileWritingMessageHandler(
-			outputDirectory	);
-		handler.handleMessage(new GenericMessage<Integer>(99));
+		subject.handleMessage(new GenericMessage<Integer>(99));
+		assertThat(outputDirectoryFile.listFiles()[0], nullValue());
 	}
 
+	@Test
+	public void supportedType() throws Exception {
+		subject.handleMessage(new GenericMessage<String>("test"));
+		assertThat(outputDirectoryFile.listFiles()[0], notNullValue());
+	}
+	
+	@After
+	public void emptyOutputDir() {
+		File[] files = outputDirectoryFile.listFiles();
+		for (File file : files) {
+			file.delete();
+		}
+	}
+
+	@AfterClass
+	public static void cleanupOutputDir() throws Exception {
+		outputDirectoryFile.delete();
+	}
 }