fetchmail.java

邮件服务器系统 支持SMTP POP3 是著名的Apache写 有一定的参考价值

/***********************************************************************
 * Copyright (c) 2003-2004 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.fetchmail;

import java.util.ArrayList;
import java.util.Collections;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Properties;

import javax.mail.MessagingException;
import javax.mail.Session;

import org.apache.avalon.cornerstone.services.scheduler.Target;
import org.apache.avalon.framework.configuration.Configurable;
import org.apache.avalon.framework.configuration.Configuration;
import org.apache.avalon.framework.configuration.ConfigurationException;
import org.apache.avalon.framework.logger.AbstractLogEnabled;
import org.apache.avalon.framework.service.ServiceException;
import org.apache.avalon.framework.service.ServiceManager;
import org.apache.james.services.MailServer;
import org.apache.james.services.UsersRepository;
import org.apache.james.services.UsersStore;

/**
 * <p>Class <code>FetchMail</code> is an Avalon task that is periodically
 * triggered to fetch mail from a JavaMail Message Store.</p>
 * 
 * <p>The lifecycle of an instance of <code>FetchMail</code> is managed by
 * Avalon. The <code>configure(Configuration)</code> method is invoked to parse
 * and validate Configuration properties. The targetTriggered(String) method is
 * invoked to execute the task.</p>
 *  
 * <p>When triggered, a sorted list of Message Store Accounts to be processed is
 * built. Each Message Store Account is processed by delegating to 
 * <code>StoreProcessor</code>.</p>
 * 
 * <p>There are two kinds of Message Store Accounts, static and dynamic. Static 
 * accounts are expliciltly declared in the Configuration. Dynamic accounts are
 * built each time the task is executed, one per each user defined to James,
 * using the James user name with a configurable prefix and suffix to define
 * the host user identity and recipient identity for each Account. Dynamic
 * accounts allow <code>FetchMail</code> to fetch mail for all James users
 * without modifying the Configuration parameters or restarting the Avalon 
 * server.</p>
 * 
 * <p>To fully understand the operations supported by this task, read the Class
 * documention for each Class in the delegation chain starting with this 
 * class' delegate, <code>StoreProcessor</code>. </p>
 * 
 * <p>Creation Date: 24-May-03</p>
 * 
 */
public class FetchMail extends AbstractLogEnabled implements Configurable, Target
{
    /**
     * Key fields for DynamicAccounts.
     */
    private class DynamicAccountKey
    {
        /**
         * The base user name without prfix or suffix
         */
        private String fieldUserName;
        
        /**
         * The sequence number of the parameters used to construct the Account
         */
        private int fieldSequenceNumber;                

        /**
         * Constructor for DynamicAccountKey.
         */
        private DynamicAccountKey()
        {
            super();
        }
        
        /**
         * Constructor for DynamicAccountKey.
         */
        public DynamicAccountKey(String userName, int sequenceNumber)
        {
            this();
            setUserName(userName);
            setSequenceNumber(sequenceNumber);
        }        

        /**
         * @see java.lang.Object#equals(Object)
         */
        public boolean equals(Object obj)
        {
            if (null == obj)
                return false;
            if (!(obj.getClass() == getClass()))
                return false;
            return (
                getUserName().equals(((DynamicAccountKey) obj).getUserName())
                    && getSequenceNumber()
                        == ((DynamicAccountKey) obj).getSequenceNumber());
        }

        /**
         * @see java.lang.Object#hashCode()
         */
        public int hashCode()
        {
            return getUserName().hashCode() ^ getSequenceNumber();
        }

        /**
         * Returns the sequenceNumber.
         * @return int
         */
        public int getSequenceNumber()
        {
            return fieldSequenceNumber;
        }

        /**
         * Returns the userName.
         * @return String
         */
        public String getUserName()
        {
            return fieldUserName;
        }

        /**
         * Sets the sequenceNumber.
         * @param sequenceNumber The sequenceNumber to set
         */
        protected void setSequenceNumber(int sequenceNumber)
        {
            fieldSequenceNumber = sequenceNumber;
        }

        /**
         * Sets the userName.
         * @param userName The userName to set
         */
        protected void setUserName(String userName)
        {
            fieldUserName = userName;
        }

    }
    /**
     * Creation Date: 06-Jun-03
     */
    private class ParsedDynamicAccountParameters
    {
        private String fieldUserPrefix;
        private String fieldUserSuffix;
        
        private String fieldPassword;
        
        private int fieldSequenceNumber;

        private boolean fieldIgnoreRecipientHeader;     
        private String fieldRecipientPrefix;
        private String fieldRecipientSuffix;

        /**
         * Constructor for ParsedDynamicAccountParameters.
         */
        private ParsedDynamicAccountParameters()
        {
            super();
        }

        /**
         * Constructor for ParsedDynamicAccountParameters.
         */
        public ParsedDynamicAccountParameters(
            int sequenceNumber,
            Configuration configuration)
            throws ConfigurationException
        {
            this();
            setSequenceNumber(sequenceNumber);
            setUserPrefix(configuration.getAttribute("userprefix", ""));
            setUserSuffix(configuration.getAttribute("usersuffix", ""));
            setRecipientPrefix(configuration.getAttribute("recipientprefix", ""));
            setRecipientSuffix(configuration.getAttribute("recipientsuffix", ""));
            setPassword(configuration.getAttribute("password"));
            setIgnoreRecipientHeader(
                configuration.getAttributeAsBoolean("ignorercpt-header"));
        }                       

        /**
         * Returns the recipientprefix.
         * @return String
         */
        public String getRecipientPrefix()
        {
            return fieldRecipientPrefix;
        }

        /**
         * Returns the recipientsuffix.
         * @return String
         */
        public String getRecipientSuffix()
        {
            return fieldRecipientSuffix;
        }

        /**
         * Returns the userprefix.
         * @return String
         */
        public String getUserPrefix()
        {
            return fieldUserPrefix;
        }

        /**
         * Returns the userSuffix.
         * @return String
         */
        public String getUserSuffix()
        {
            return fieldUserSuffix;
        }

        /**
         * Sets the recipientprefix.
         * @param recipientprefix The recipientprefix to set
         */
        protected void setRecipientPrefix(String recipientprefix)
        {
            fieldRecipientPrefix = recipientprefix;
        }

        /**
         * Sets the recipientsuffix.
         * @param recipientsuffix The recipientsuffix to set
         */
        protected void setRecipientSuffix(String recipientsuffix)
        {
            fieldRecipientSuffix = recipientsuffix;
        }

        /**
         * Sets the userprefix.
         * @param userprefix The userprefix to set
         */
        protected void setUserPrefix(String userprefix)
        {
            fieldUserPrefix = userprefix;
        }

        /**
         * Sets the userSuffix.
         * @param userSuffix The userSuffix to set
         */
        protected void setUserSuffix(String userSuffix)
        {
            fieldUserSuffix = userSuffix;
        }

        /**
         * Returns the password.
         * @return String
         */
        public String getPassword()
        {
            return fieldPassword;
        }

        /**
         * Sets the ignoreRecipientHeader.
         * @param ignoreRecipientHeader The ignoreRecipientHeader to set
         */
        protected void setIgnoreRecipientHeader(boolean ignoreRecipientHeader)
        {
            fieldIgnoreRecipientHeader = ignoreRecipientHeader;
        }

        /**
         * Sets the password.
         * @param password The password to set
         */
        protected void setPassword(String password)
        {
            fieldPassword = password;
        }

        /**
         * Returns the ignoreRecipientHeader.
         * @return boolean
         */
        public boolean isIgnoreRecipientHeader()
        {
            return fieldIgnoreRecipientHeader;
        }

        /**
         * Returns the sequenceNumber.
         * @return int
         */
        public int getSequenceNumber()
        {
            return fieldSequenceNumber;
        }

        /**
         * Sets the sequenceNumber.
         * @param sequenceNumber The sequenceNumber to set
         */
        protected void setSequenceNumber(int sequenceNumber)
        {
            fieldSequenceNumber = sequenceNumber;
        }

    }
    /**
     * @see org.apache.avalon.cornerstone.services.scheduler.Target#targetTriggered(String)
     */
    private boolean fieldFetching = false;
    
    /**
     * The Configuration for this task
     */
    private ParsedConfiguration fieldConfiguration;
    
    /**
     * A List of ParsedDynamicAccountParameters, one for every <alllocal> entry
     * in the configuration.
     */
    private List fieldParsedDynamicAccountParameters;    
    
    /**
     * The Static Accounts for this task.
     * These are setup when the task is configured.
     */
    private List fieldStaticAccounts;
    
    /**
     * The JavaMail Session for this fetch task.
     */ 

    private Session fieldSession;
    
    /**
     * The Dynamic Accounts for this task.
     * These are setup each time the fetchtask is run.
     */
    private Map fieldDynamicAccounts;        
    
   /**
     * The MailServer service
     */
    private MailServer fieldServer;
    
   /**
     * The Local Users repository
     */
    private UsersRepository fieldLocalUsers;        

    /**
     * Constructor for POP3mail.
     */
    public FetchMail()
    {
        super();
    }

    /**
     * Method configure parses and validates the Configuration data and creates
     * a new <code>ParsedConfiguration</code>, an <code>Account</code> for each
     * configured static account and a <code>ParsedDynamicAccountParameters</code>
     * for each dynamic account.
     * 
     * @see org.apache.avalon.framework.configuration.Configurable#configure(Configuration)
     */
    public void configure(Configuration configuration)
        throws ConfigurationException
    {
        // Set any Session parameters passed in the Configuration
        setSessionParameters(configuration);

        // Create the ParsedConfiguration used in the delegation chain
        ParsedConfiguration parsedConfiguration =
            new ParsedConfiguration(
                configuration,
                getLogger(),
                getServer(),
                getLocalUsers());
        setConfiguration(parsedConfiguration);

        // Setup the Accounts
        Configuration[] allAccounts = configuration.getChildren("accounts");
        if (allAccounts.length < 1)
            throw new ConfigurationException("Missing <accounts> section.");
        if (allAccounts.length > 1)
            throw new ConfigurationException("Too many <accounts> sections, there must be exactly one");
        Configuration accounts = allAccounts[0];

        // Create an Account for every configured account
        Configuration[] accountsChildren = accounts.getChildren();
        if (accountsChildren.length < 1)
            throw new ConfigurationException("Missing <account> section.");

        for (int i = 0; i < accountsChildren.length; i++)
        {
            Configuration accountsChild = accountsChildren[i];

            if (accountsChild.getName() == "alllocal")
            {
                // <allLocal> is dynamic, save the parameters for accounts to
                // be created when the task is triggered
                getParsedDynamicAccountParameters().add(
                    new ParsedDynamicAccountParameters(i, accountsChild));
                continue;
            }

            if (accountsChild.getName() == "account")
            {
                // Create an Account for the named user and
                // add it to the list of static accounts
                getStaticAccounts().add(
                    new Account(
                        i,
                        parsedConfiguration,
                        accountsChild.getAttribute("user"),
                        accountsChild.getAttribute("password"),
                        accountsChild.getAttribute("recipient"),
                        accountsChild.getAttributeAsBoolean(
                            "ignorercpt-header"),
                        getSession()));
                continue;
            }

            throw new ConfigurationException(
                "Illegal token: <"
                    + accountsChild.getName()
                    + "> in <accounts>");
        }
    }

    /**
     * Method target triggered fetches mail for each configured account.
     * 
     * @see org.apache.avalon.cornerstone.services.scheduler.Target#targetTriggered(String)
     */
    public void targetTriggered(String arg0)
    {
        // if we are already fetching then just return
        if (isFetching())
        {
            getLogger().info(
                "Triggered fetch cancelled. A fetch is already in progress.");
            return;
        }

        // Enter Fetching State
        try
        {
            setFetching(true);
            getLogger().info("Fetcher starting fetches");

            // if debugging, list the JavaMail property key/value pairs
            // for this Session
            if (getLogger().isDebugEnabled())