Java example source code file (SmtpRequests.java)

This example Java source code file (SmtpRequests.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

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Java - Java tags/keywords

asciistring, charsequence, data, from, from_null_sender, help_no_arg, list, noop, quit, rset, smtprequest, smtprequests, unstableapi, util

The SmtpRequests.java Java example source code

/*
 * Copyright 2016 The Netty Project
 *
 * The Netty Project licenses this file to you 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 io.netty.handler.codec.smtp;

import io.netty.util.AsciiString;
import io.netty.util.internal.ObjectUtil;
import io.netty.util.internal.UnstableApi;

import java.util.ArrayList;
import java.util.List;

/**
 * Provides utility methods to create {@link SmtpRequest}s.
 */
@UnstableApi
public final class SmtpRequests {

    private static final SmtpRequest DATA = new DefaultSmtpRequest(SmtpCommand.DATA);
    private static final SmtpRequest NOOP = new DefaultSmtpRequest(SmtpCommand.NOOP);
    private static final SmtpRequest RSET = new DefaultSmtpRequest(SmtpCommand.RSET);
    private static final SmtpRequest HELP_NO_ARG = new DefaultSmtpRequest(SmtpCommand.HELP);
    private static final SmtpRequest QUIT = new DefaultSmtpRequest(SmtpCommand.QUIT);
    private static final AsciiString FROM_NULL_SENDER = new AsciiString("FROM:<>");

    /**
     * Creates a {@code HELO} request.
     */
    public static SmtpRequest helo(CharSequence hostname) {
        return new DefaultSmtpRequest(SmtpCommand.HELO, hostname);
    }

    /**
     * Creates a {@code EHLO} request.
     */
    public static SmtpRequest ehlo(CharSequence hostname) {
        return new DefaultSmtpRequest(SmtpCommand.EHLO, hostname);
    }

    /**
     * Creates a {@code NOOP} request.
     */
    public static SmtpRequest noop() {
        return NOOP;
    }

    /**
     * Creates a {@code DATA} request.
     */
    public static SmtpRequest data() {
        return DATA;
    }

    /**
     * Creates a {@code RSET} request.
     */
    public static SmtpRequest rset() {
        return RSET;
    }

    /**
     * Creates a {@code HELP} request.
     */
    public static SmtpRequest help(String cmd) {
        return cmd == null ? HELP_NO_ARG : new DefaultSmtpRequest(SmtpCommand.HELP, cmd);
    }

    /**
     * Creates a {@code QUIT} request.
     */
    public static SmtpRequest quit() {
        return QUIT;
    }

    /**
     * Creates a {@code MAIL} request.
     */
    public static SmtpRequest mail(CharSequence sender, CharSequence... mailParameters) {
        if (mailParameters == null || mailParameters.length == 0) {
            return new DefaultSmtpRequest(SmtpCommand.MAIL,
                                          sender != null ? "FROM:<" + sender + '>' : FROM_NULL_SENDER);
        } else {
            List<CharSequence> params = new ArrayList(mailParameters.length + 1);
            params.add(sender != null? "FROM:<" + sender + '>' : FROM_NULL_SENDER);
            for (CharSequence param : mailParameters) {
                params.add(param);
            }
            return new DefaultSmtpRequest(SmtpCommand.MAIL, params);
        }
    }

    /**
     * Creates a {@code RCPT} request.
     */
    public static SmtpRequest rcpt(CharSequence recipient, CharSequence... rcptParameters) {
        ObjectUtil.checkNotNull(recipient, "recipient");
        if (rcptParameters == null || rcptParameters.length == 0) {
            return new DefaultSmtpRequest(SmtpCommand.RCPT, "TO:<" + recipient + '>');
        } else {
            List<CharSequence> params = new ArrayList(rcptParameters.length + 1);
            params.add("TO:<" + recipient + '>');
            for (CharSequence param : rcptParameters) {
                params.add(param);
            }
            return new DefaultSmtpRequest(SmtpCommand.RCPT, params);
        }
    }

    /**
     * Creates a {@code EXPN} request.
     */
    public static SmtpRequest expn(CharSequence mailingList) {
        return new DefaultSmtpRequest(SmtpCommand.EXPN, ObjectUtil.checkNotNull(mailingList, "mailingList"));
    }

    /**
     * Creates a {@code VRFY} request.
     */
    public static SmtpRequest vrfy(CharSequence user) {
        return new DefaultSmtpRequest(SmtpCommand.VRFY, ObjectUtil.checkNotNull(user, "user"));
    }

    private SmtpRequests() { }
}