Java tutorial
/* * Copyright 2002-2013 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 com.japp; import java.io.File; import java.io.IOException; import java.util.Locale; import org.apache.commons.io.FileUtils; import org.apache.commons.io.FilenameUtils; import org.springframework.integration.Message; import org.springframework.integration.annotation.Transformer; import org.springframework.integration.file.FileHeaders; import org.springframework.integration.support.MessageBuilder; public class FileCompressor { /** * Actual Spring Integration transformation handler. * * @param inputMessage Spring Integration input message * @return New Spring Integration message with updated headers */ @Transformer public Message<String> handleFile(final Message<File> inputMessage) { final File inputFile = inputMessage.getPayload(); final String filename = inputFile.getName(); final String fileExtension = FilenameUtils.getExtension(filename); final String inputAsString; try { inputAsString = FileUtils.readFileToString(inputFile); } catch (IOException e) { throw new IllegalStateException(e); } final Message<String> message = MessageBuilder.withPayload(inputAsString.toUpperCase(Locale.ENGLISH)) .setHeader(FileHeaders.FILENAME, filename).setHeader(FileHeaders.ORIGINAL_FILE, inputFile) .setHeader("file_size", inputFile.length()).setHeader("file_extension", fileExtension).build(); return message; } }