Java tutorial
/* * Copyright 2016-2019 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 * * https://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.mail.support; import java.util.Date; import java.util.Enumeration; import java.util.Map; import javax.mail.Header; import javax.mail.internet.MimeMessage; import org.springframework.integration.mail.MailHeaders; import org.springframework.integration.mapping.HeaderMapper; import org.springframework.messaging.MessageHeaders; import org.springframework.messaging.MessagingException; import org.springframework.util.LinkedMultiValueMap; import org.springframework.util.MultiValueMap; /** * Maps an inbound {@link MimeMessage} to a {@link Map}. * * @author Gary Russell * @since 4.3 * */ public class DefaultMailHeaderMapper implements HeaderMapper<MimeMessage> { @Override public void fromHeaders(MessageHeaders headers, MimeMessage target) { throw new UnsupportedOperationException("Mapping to a mail message is not currently supported"); } @Override public Map<String, Object> toHeaders(MimeMessage source) { Map<String, Object> headers = MailUtils.extractStandardHeaders(source); try { Enumeration<?> allHeaders = source.getAllHeaders(); MultiValueMap<String, String> rawHeaders = new LinkedMultiValueMap<String, String>(); while (allHeaders.hasMoreElements()) { Object headerInstance = allHeaders.nextElement(); if (headerInstance instanceof Header) { Header header = (Header) headerInstance; rawHeaders.add(header.getName(), header.getValue()); } } headers.put(MailHeaders.RAW_HEADERS, rawHeaders); headers.put(MailHeaders.FLAGS, source.getFlags()); int lineCount = source.getLineCount(); if (lineCount > 0) { headers.put(MailHeaders.LINE_COUNT, lineCount); } Date receivedDate = source.getReceivedDate(); if (receivedDate != null) { headers.put(MailHeaders.RECEIVED_DATE, receivedDate); } int size = source.getSize(); if (size > 0) { headers.put(MailHeaders.SIZE, size); } headers.put(MailHeaders.EXPUNGED, source.isExpunged()); headers.put(MailHeaders.CONTENT_TYPE, source.getContentType()); } catch (Exception e) { throw new MessagingException("Failed to map message headers", e); } return headers; } }