Added file source adapter and supporting classes.

spring-integration-core/src/main/java/org/springframework/integration/adapter/file/AbstractFileMapper.java

@@ -0,0 +1,101 @@
+/*
+ * Copyright 2002-2007 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.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.integration.adapter.file;
+
+import java.io.File;
+import java.io.FileReader;
+import java.io.FileWriter;
+
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+
+import org.springframework.integration.MessageHandlingException;
+import org.springframework.integration.message.AbstractMessageMapper;
+import org.springframework.integration.message.GenericMessage;
+import org.springframework.integration.message.Message;
+import org.springframework.util.Assert;
+import org.springframework.util.FileCopyUtils;
+
+/**
+ * Base class providing common behavior for file-based message mappers.
+ * 
+ * @author Mark Fisher
+ */
+public abstract class AbstractFileMapper<T> extends AbstractMessageMapper<T, File> {
+
+	protected Log logger = LogFactory.getLog(this.getClass());
+
+	private File parentDirectory;
+
+	private File backupDirectory;
+
+	private FileNameGenerator fileNameGenerator = new DefaultFileNameGenerator();
+
+
+	public AbstractFileMapper(File parentDirectory) {
+		this.parentDirectory = parentDirectory;
+	}
+
+	public void setBackupDirectory(File backupDirectory) {
+		this.backupDirectory = backupDirectory;
+	}
+
+	public void setFileNameGenerator(FileNameGenerator fileNameGenerator) {
+		Assert.notNull(fileNameGenerator, "'fileNameGenerator' must not be null");
+		this.fileNameGenerator = fileNameGenerator;
+	}
+
+	public File fromMessage(Message<T> message) {
+		try {
+			File file = new File(parentDirectory, this.fileNameGenerator.generateFileName(message));
+			this.writeToFile(file, message.getPayload());
+			return file;
+		}
+		catch (Exception e) {
+			throw new MessageHandlingException("failure occurred mapping file to message", e);
+		}
+	}
+
+	public Message<T> toMessage(File file) {
+		try {
+			T payload = this.readMessagePayload(file);
+			if (payload == null) {
+				return null;
+			}
+			Message<T> message = new GenericMessage<T>(this.getUidGenerator().generateUid(), payload);
+			if (this.backupDirectory != null) {
+				FileWriter writer = new FileWriter(this.backupDirectory.getAbsolutePath() +
+						File.separator + file.getName());
+				FileCopyUtils.copy(new FileReader(file), writer);
+			}
+			file.delete();
+			return message;
+		}
+		catch (Exception e) {
+			String errorMessage = "failure occurred mapping file to message";
+			if (logger.isWarnEnabled()) {
+				logger.warn(errorMessage, e);
+			}
+			throw new MessageHandlingException(errorMessage, e);
+		}
+	}
+
+	protected abstract T readMessagePayload(File file) throws Exception;
+
+	protected abstract void writeToFile(File file, T payload) throws Exception;
+
+}

spring-integration-core/src/main/java/org/springframework/integration/adapter/file/ByteArrayFileMapper.java

@@ -0,0 +1,46 @@
+/*
+ * Copyright 2002-2007 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.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.integration.adapter.file;
+
+import java.io.File;
+
+import org.springframework.util.FileCopyUtils;
+
+/**
+ * A {@link org.springframework.integration.message.MessageMapper}
+ * implementation for messages with a byte array payload.
+ * 
+ * @author Mark Fisher
+ */
+public class ByteArrayFileMapper extends AbstractFileMapper<byte[]> {
+
+	public ByteArrayFileMapper(File parentDirectory) {
+		super(parentDirectory);
+	}
+
+
+	@Override
+	protected byte[] readMessagePayload(File file) throws Exception {
+		return FileCopyUtils.copyToByteArray(file);
+	}
+
+	@Override
+	protected void writeToFile(File file, byte[] payload) throws Exception {
+		FileCopyUtils.copy(payload, file);
+	}
+
+}

spring-integration-core/src/main/java/org/springframework/integration/adapter/file/DefaultFileNameGenerator.java

@@ -0,0 +1,33 @@
+/*
+ * Copyright 2002-2007 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.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.integration.adapter.file;
+
+import org.springframework.integration.message.Message;
+
+/**
+ * Default implementation of the filename generator strategy. Concatenates the
+ * message id and the current timestamp.
+ * 
+ * @author Mark Fisher
+ */
+public class DefaultFileNameGenerator implements FileNameGenerator {
+
+	public String generateFileName(Message<?> message) {
+		return message.getId() + "-" + System.currentTimeMillis() + ".msg";
+	}
+
+}

spring-integration-core/src/main/java/org/springframework/integration/adapter/file/FileNameGenerator.java

@@ -0,0 +1,30 @@
+/*
+ * Copyright 2002-2007 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.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.integration.adapter.file;
+
+import org.springframework.integration.message.Message;
+
+/**
+ * Strategy interface for generating a file name from a message.
+ * 
+ * @author Mark Fisher
+ */
+public interface FileNameGenerator {
+
+	String generateFileName(Message<?> message);
+
+}

spring-integration-core/src/main/java/org/springframework/integration/adapter/file/FileSource.java

@@ -0,0 +1,80 @@
+/*
+ * Copyright 2002-2007 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.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.integration.adapter.file;
+
+import java.io.File;
+import java.io.FileFilter;
+import java.io.FilenameFilter;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.List;
+
+import org.springframework.integration.MessageHandlingException;
+import org.springframework.integration.adapter.PollableSource;
+import org.springframework.util.Assert;
+
+/**
+ * A messaging source that polls a directory to retrieve files.
+ * 
+ * @author Mark Fisher
+ */
+public class FileSource implements PollableSource<File> {
+
+	private File directory;
+
+	private FileFilter fileFilter;
+
+	private FilenameFilter filenameFilter;
+
+
+	public FileSource(File directory) {
+		Assert.notNull("directory must not be null");
+		this.directory = directory;
+	}
+
+	public void setFileFilter(FileFilter fileFilter) {
+		this.fileFilter = fileFilter;
+	}
+
+	public void setFilenameFilter(FilenameFilter filenameFilter) {
+		this.filenameFilter = filenameFilter;
+	}
+
+	public Collection<File> poll(int limit) {
+		File[] files = null;
+		if (this.fileFilter != null) {
+			files = this.directory.listFiles(fileFilter);
+		}
+		else if (this.filenameFilter != null) {
+			files = this.directory.listFiles(filenameFilter);
+		}
+		else {
+			files = this.directory.listFiles();
+		}
+		if (files == null) {
+			throw new MessageHandlingException("Problem occurred while polling for files. " +
+					"Is '" + directory.getAbsolutePath() + "' a directory?");
+		}
+		int size = Math.min(limit, files.length);
+		List<File> results = new ArrayList<File>(size);
+		for (int i = 0; i < size; i++) {
+			results.add(files[i]);
+		}
+		return results;
+	}
+
+}

spring-integration-core/src/main/java/org/springframework/integration/adapter/file/FileSourceAdapter.java

@@ -0,0 +1,55 @@
+/*
+ * Copyright 2002-2007 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.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.integration.adapter.file;
+
+import java.io.File;
+
+import org.springframework.integration.adapter.PollingSourceAdapter;
+import org.springframework.integration.channel.MessageChannel;
+import org.springframework.integration.message.MessageMapper;
+import org.springframework.util.Assert;
+
+/**
+ * Channel adapter for polling a directory and creating messages from its files.
+ * 
+ * @author Mark Fisher
+ */
+public class FileSourceAdapter extends PollingSourceAdapter<File> {
+
+	public FileSourceAdapter(File directory, MessageChannel channel, int pollInterval) {
+		this(directory, channel, pollInterval, true);
+	}
+
+	public FileSourceAdapter(File directory, MessageChannel channel, int pollInterval, boolean isTextBased) {
+		super(new FileSource(directory), channel, pollInterval);
+		if (isTextBased) {
+			this.setMessageMapper(new TextFileMapper(directory));
+		}
+		else {
+			this.setMessageMapper(new ByteArrayFileMapper(directory));
+		}
+	}
+
+	public void setBackupDirectory(File backupDirectory) {
+		Assert.notNull(backupDirectory, "'backupDirectory' must not be null");
+		MessageMapper<?, File> mapper = this.getMessageMapper();
+		if (mapper != null && (mapper instanceof AbstractFileMapper<?>)) {
+			((AbstractFileMapper<?>) mapper).setBackupDirectory(backupDirectory);
+		}
+	}
+
+}

spring-integration-core/src/main/java/org/springframework/integration/adapter/file/TextFileMapper.java

@@ -0,0 +1,48 @@
+/*
+ * Copyright 2002-2007 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.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.integration.adapter.file;
+
+import java.io.File;
+import java.io.FileReader;
+import java.io.FileWriter;
+
+import org.springframework.util.FileCopyUtils;
+
+/**
+ * A {@link org.springframework.integration.message.MessageMapper}
+ * implementation for messages with a String payload.
+ * 
+ * @author Mark Fisher
+ */
+public class TextFileMapper extends AbstractFileMapper<String> {
+
+	public TextFileMapper(File parentDirectory) {
+		super(parentDirectory);
+	}
+
+
+	@Override
+	protected String readMessagePayload(File file) throws Exception {
+		return FileCopyUtils.copyToString(new FileReader(file));
+	}
+
+	@Override
+	protected void writeToFile(File file, String payload) throws Exception {
+		FileCopyUtils.copy(payload, new FileWriter(file));
+	}
+
+}