mailheaders.java

java 开发的邮件服务器平台。支持以下协议。 协议可以修改为自己的专门标识

/***********************************************************************
 * Copyright (c) 2000-2004 The Apache Software Foundation.             *
 * All rights reserved.                                                *
 * ------------------------------------------------------------------- *
 * 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.apache.james.core;

import javax.mail.MessagingException;
import javax.mail.internet.InternetHeaders;
import java.io.*;
import java.util.Enumeration;

import org.apache.james.util.RFC2822Headers;

/**
 * This interface defines a container for mail headers. Each header must use
 * MIME format: <pre>name: value</pre>.
 *
 */
public class MailHeaders extends InternetHeaders implements Serializable, Cloneable {

    /**
     * No argument constructor
     *
     * @throws MessagingException if the super class cannot be properly instantiated
     */
    public MailHeaders() throws MessagingException {
        super();
    }

    /**
     * Constructor that takes an InputStream containing the contents
     * of the set of mail headers.
     *
     * @param in the InputStream containing the header data
     *
     * @throws MessagingException if the super class cannot be properly instantiated
     *                            based on the stream
     */
    public MailHeaders(InputStream in) throws MessagingException {
        super(in);
    }

    /**
     * Write the headers to an output stream
     *
     * @param writer the stream to which to write the headers
     */
    public void writeTo(OutputStream out) {
        PrintStream pout;
        if (out instanceof PrintStream) {
            pout = (PrintStream)out;
        } else {
            pout = new PrintStream(out);
        }
        for (Enumeration e = super.getAllHeaderLines(); e.hasMoreElements(); ) {
            pout.print((String) e.nextElement());
            pout.print("\r\n");
        }
        // Print trailing CRLF
        pout.print("\r\n");
    }

    /**
     * Generate a representation of the headers as a series of bytes.
     *
     * @return the byte array containing the headers
     */
    public byte[] toByteArray() {
        ByteArrayOutputStream headersBytes = new ByteArrayOutputStream();
        writeTo(headersBytes);
        return headersBytes.toByteArray();
    }

    /**
     * Check if a particular header is present.
     *
     * @return true if the header is present, false otherwise
     */
    public boolean isSet(String name) {
        String[] value = super.getHeader(name);
        return (value != null && value.length != 0);
    }

    /**
     * Check if all REQUIRED headers fields as specified in RFC 822
     * are present.
     *
     * @return true if the headers are present, false otherwise
     */
    public boolean isValid() {
        return (isSet(RFC2822Headers.DATE) && isSet(RFC2822Headers.TO) && isSet(RFC2822Headers.FROM));
    }
}