env.java

用Java写的面相对象的数据库管理系统

// You can redistribute this software and/or modify it under the terms of
// the Ozone Core License version 1 published by ozone-db.org.
//
// The original code and portions created by SMB are
// Copyright (C) 1997-2000 by SMB GmbH. All rights reserved.
//
// $Id: Env.java,v 1.70 2000/11/03 13:57:18 daniela Exp $

package org.ozoneDB.core;

import java.io.*;
import java.util.*;
import org.ozoneDB.DxLib.*;
import org.ozoneDB.*;
import org.ozoneDB.core.DbRemote.*;
import org.ozoneDB.core.dr.*;
import org.ozoneDB.util.*;


/**
 * Env is the environment of a ozone database server. Currently there
 * is only one environment allowed per JVM. A server environment can be
 * initialized by the a Server or by a LocalDatabase.
 * 
 * 
 * @author <a href="http://www.softwarebuero.de/">SMB</a>
 * @version $Revision: 1.70 $Date: 2000/11/03 13:57:18 $
 */
public final class Env implements Observer {
    
    // constant members ***********************************
    public final static String VERSION = "0.6";
    public final static String OS_DIR = "ostab";
    public final static String STATE_FILE = "state.properties";
    public final static String CONFIG_FILE = "config.properties";
    public final static String LOG_FILE = "log";
    public final static String DATA_DIR = "data" + File.separator;
    public final static String STATS_DIR = "stats";
    
    /**
     * AdminPort and InvokeServer accepts and admin requests
     */
    public final static int ACCEPT_THREAD_PRIORITY = Thread.NORM_PRIORITY + 2;
    
    /**
     * Thread priority of normal transaction.
     */
    public final static int TRANSACTION_THREAD_PRIORITY = Thread.NORM_PRIORITY;
    
    public final static int TRANSACTION_MUTEX_PRIORITY = TRANSACTION_THREAD_PRIORITY + 1;
    
    /**
     * Thread priority deadlock recognition.
     */
    public final static int DEADLOCK_THREAD_PRIORITY = Thread.NORM_PRIORITY;
    
    /**
     * Priority of the server thread (Server.main())
     */
    public final static int SERVER_THREAD_PRIORITY = Thread.NORM_PRIORITY + 2;
    
    
    // class members **************************************
    
    /**
     * The one and only ozone environment of this VM.
     */
    public static Env theEnv;
    
    protected static OzoneSecurityManager securityManager;
    
    
    // instance members ***********************************
    
    public String dir;
    
    /**
     * Holds the content of the 'state.properties' file. After
     * changing the content the state must be written to disk to make
     * changes persistent.
     */
    public Setup state;
    
    /**
     * Holds the content of the 'config.properties' config file.
     */
    public Setup config;
    
    public LogWriter logWriter = new LogWriter();
    
    /**
     * This indicates that we are about to shutdown.
     */
    public boolean shuttingdown = false;
    
    protected long idCount = 0;
    protected long idBorder = 0;
    protected long idRange = 1000;
    
    protected long totalMemory;
    
    /**
     * Interface for the database objects inside the server.
     */
    public Database database;
    
    public ClassManager classManager;
    
    public TransactionManager transactionManager;
    
    public Store store;
    
    public UserManager userManager;
    
    protected InvokeServer invokeServer;
    
    protected AdminPort adminPort;
    
    protected DeadlockThread deadlockThread;
    
    protected DeadlockRecognition dr;
    
    
    // class methods **************************************
    
    /**
     * Returns the environment of the current thread. Useful for objects that
     * do not store the enviroment itself like ObjectContainer.
     * 
     * 
     * @return The environment of the current thread or null if called outside
     * the server.
     */
    public static Env currentEnv() {
        return theEnv;
    } 
    
    
    // instance methods ***********************************
    
    /**
     * Construct a new ozone server environment.
     * 
     * 
     * @param _dirName Directory of the database.
     * @param _local
     */
    public Env( String _dirName, int _debugLevel, boolean _verbose, boolean _local ) throws Exception{
        
        if (theEnv != null) {
            throw new Exception( "ozone environment (Env) already initialized for this VM" );
        } 
        
        try {
            // give the engine its environment first but don't forget to
            // reset it if we catch an exception
            theEnv = this;
            
            dir = new String( _dirName ) + File.separator;
            if (!new File( dir ).isDirectory()) {
                throw new Exception( "No database found at '" + dir + "'." );
            } 
            
            initSetup();
            initLogs( _local, _debugLevel );
            
            logWriter.newEntry( this, "Copyright (C) 1997-2000 The Ozone Database Project", LogWriter.INFO );
            logWriter.newEntry( this, "contains libraries from the Apache Software Foundation", LogWriter.INFO );
            logWriter.newEntry( this, "contains libraries from SUN microsystems", LogWriter.INFO );
            logWriter.newEntry( this, "contains libraries from the W3C", LogWriter.INFO );
            logWriter.newEntry( this, "contains libraries from Exoffice, Inc.", LogWriter.INFO );
            logWriter.newEntry( this, "contains libraries (JavaClass) from Markus Dahm ", LogWriter.INFO );
            logWriter.newEntry( this, "Copyright (C) under owner's respective terms.", LogWriter.INFO );
            
            if (System.getSecurityManager() == null) {
                securityManager = new OzoneSecurityManager();
                System.setSecurityManager( securityManager );
            } 
            
            calcMemory();
            
            database = new Database( this );
            
            classManager = new ClassManager( this );
            classManager.startup();
            
            // UserManager has to be initialized before the recovery
            userManager = new UserManager( this );
            userManager.startup();
            
            transactionManager = new TransactionManager( this );
            transactionManager.startup();
            
            // initialize the store
            String storeClassName = config.stringProperty( Setup.STORE, "org.ozoneDB.core.wizardStore.WizardStore" );
            Class storeClass = Class.forName( storeClassName );
            if (storeClass == null) {
                logWriter.newEntry( this, "Store not found: " + storeClassName, LogWriter.ERROR );
                System.exit( 1 );
            } 
            store = (Store)storeClass.newInstance();
            store.init( this );
            store.startup();
        } catch (Exception e) {
            theEnv = null;
            if (logWriter != null) {
                logWriter.newEntry( this, "Unable to initialize server.", e, LogWriter.ERROR );
            } else {
                System.out.println( "Unable to initialize server." );
                e.printStackTrace();
            } 
            throw e;
        } 
    }
    
    
    public void startExternalEventProcessing() throws Exception {
        try {
            invokeServer = new InvokeServer( this, portNum() );
            invokeServer.startup();
            invokeServer.accept();
            
            adminPort = new AdminPort( this, adminPortNum() );
            adminPort.startup();
            
            logWriter.newEntry( this, "external event processing started", LogWriter.INFO );
        } catch (Exception e) {
            logWriter.newEntry( this,
                    "Client port (" + portNum() + ") or admin port (" + adminPortNum() + ") are already in use.", e,
                    LogWriter.ERROR );
            throw e;
        } 
    } 
    
    
    public void startDeadlockRecognition() {
        logWriter.newEntry( this, "deadlock recognition started", LogWriter.INFO );
        deadlockThread = new DeadlockThread( 3000, transactionManager );
        deadlockThread.setPriority( DEADLOCK_THREAD_PRIORITY );
        deadlockThread.setDaemon( true );
        deadlockThread.start();
    } 
    
    
    /**
     * Initialize the setup (state and config) of this server environment. When
     * searching specific property look in setup file first, then in the
     * properties file, then use defaults, then use System properties.
     */
    protected void initSetup() throws Exception {
        Setup defaults = new Setup( this );
        defaults.fillWithOzoneDefaults();
        
        FileInputStream configIn = new FileInputStream( new File( dir, CONFIG_FILE ) );
        FileInputStream stateIn = new FileInputStream( new File( dir, STATE_FILE ) );
        try {
            config = new Setup( this, defaults );
            config.load( configIn );
            config.addProperties( System.getProperties(), "ozoneDB." );
            config.print( System.out, "ozoneDB.", "    " );
            
            state = new Setup( this );
            state.load( stateIn );
        } finally {
            configIn.close();
            stateIn.close();