env.java

用Java写的面相对象的数据库管理系统

        } 
    } 
    
    
    /**
     * Save the setup (state and config) of the current server environment.
     */
    protected void storeSetup() throws Exception {
        OutputStream stateOut = 
                new BufferedOutputStream( new FileOutputStream( new File( dir, STATE_FILE ) ), 4 * 1024 );
        OutputStream configOut = new BufferedOutputStream( new FileOutputStream( new File( dir, CONFIG_FILE ) ), 4096 );
        try {
            // save state
            state.save( stateOut, "Ozone Server State File.\n#Do not edit!" );
            
            // save config
            StringBuffer head = new StringBuffer( 1024 );
            head.append( "Ozone Server Config File.\n" );
            head.append( "#\n" );
            head.append( "# Do not use comments. This file will be overwritten,\n" );
            head.append( "# if the config changes. See the ozone documentation\n" );
            head.append( "# for details about the properties and their values.\n" );
            config.save( configOut, head.toString() );
        } finally {
            stateOut.close();
            configOut.close();
        } 
    } 
    
    
    /**
     * Env is an Observer that observes its Setup object to write changes to
     * disk.
     */
    public void update( Observable observable, Object obj ) {
        logWriter.newEntry( this, "update()", LogWriter.DEBUG );
        
        try {
            if (obj == state) {
                logWriter.newEntry( this, "    state has changed...", LogWriter.DEBUG );
                storeSetup();
            } else if (obj == config) {
                logWriter.newEntry( this, "    config has changed...", LogWriter.DEBUG );
                storeSetup();
            } else {
                throw new RuntimeException( "Don't know specified Observable object." );
            } 
        } catch (Exception e) {
            logWriter.newEntry( this, "update(): ", e, LogWriter.WARN );
            throw new RuntimeException( e.toString() );
        } 
    } 
    
    
    /**
     * Initialize server logging. If the server runs standalone, there are two
     * LogTarget: stdout and file. Which log messages are written to which target
     * is specified in the config file. If the server runs in debug mode, debug
     * messages are written to each target.
     */
    protected void initLogs( boolean _local, int _debugLevel ) throws Exception {
        DxCollection stdoutList = config.stringsProperty( Setup.STDOUT_LOG, "" );
        DxCollection fileList = config.stringsProperty( Setup.FILE_LOG, "" );
        
        int stdoutFlags = 0;
        for (DxIterator it = stdoutList.iterator(); it.next() != null;) {
            String entry = (String)it.object();
            if (entry.equals( "WARN" )) {
                stdoutFlags |= LogWriter.WARN;
            } 
            if (entry.equals( "ERROR" )) {
                stdoutFlags |= LogWriter.ERROR;
            } 
            if (entry.equals( "INFO" )) {
                stdoutFlags |= LogWriter.INFO;
            } 
            if (entry.equals( "DEBUG" )) {
                stdoutFlags |= LogWriter.DEBUG;
            } 
            if (entry.equals( "DEBUG2" )) {
                stdoutFlags |= LogWriter.DEBUG2;
            } 
            if (entry.equals( "DEBUG3" )) {
                stdoutFlags |= LogWriter.DEBUG3;
            } 
        //                stdoutFlags = stdoutFlags | LogWriter.DEBUG | LogWriter.DEBUG2 | LogWriter.DEBUG3;
        } 
        
        int fileFlags = 0;
        for (DxIterator it = fileList.iterator(); it.next() != null;) {
            String entry = (String)it.object();
            if (entry.equals( "WARN" )) {
                fileFlags |= LogWriter.WARN;
            } 
            if (entry.equals( "ERROR" )) {
                fileFlags |= LogWriter.ERROR;
            } 
            if (entry.equals( "INFO" )) {
                fileFlags |= LogWriter.INFO;
            } 
            if (entry.equals( "DEBUG" )) {
                fileFlags |= LogWriter.DEBUG;
            } 
            if (entry.equals( "DEBUG2" )) {
                fileFlags |= LogWriter.DEBUG2;
            } 
            if (entry.equals( "DEBUG3" )) {
                fileFlags |= LogWriter.DEBUG3;
            } 
        } 
        
        if (_local) {
            logWriter.addLogTarget( new FileOutputStream( dir + LOG_FILE ), fileFlags | _debugLevel );
        } else {
            logWriter.addLogTarget( new FileOutputStream( dir + LOG_FILE ), fileFlags | _debugLevel );
            logWriter.addLogTarget( System.out, stdoutFlags | _debugLevel );
        } 
    } 
    
    
    public void shutdown() {
        shuttingdown = true;
        try {
            logWriter.newEntry( this, "shutdown...", LogWriter.INFO );
            
            //            if (storageFrame != null) {
            //               storageFrame.dispose();
            //               storageFrame = null;
            //               logWriter.newEntry (this, "ozonometer closed.", LogWriter.INFO);
            //               }
            if (invokeServer != null) {
                invokeServer.shutdown();
                invokeServer = null;
            } 
            if (adminPort != null) {
                adminPort.shutdown();
                adminPort = null;
            } 
            if (deadlockThread != null) {
                deadlockThread.stop();
                deadlockThread = null;
                logWriter.newEntry( this, "Deadlock recognition stopped.", LogWriter.INFO );
            } 
            
            transactionManager.shutdown();
            transactionManager = null;
            
            store.shutdown();
            store = null;
            
            userManager.shutdown();
            userManager = null;
            
            classManager.shutdown();
            classManager = null;
            
            storeSetup();
            
            logWriter.newEntry( this, "Bye.", LogWriter.INFO );
            theEnv = null;
        } catch (Exception e) {
            fatalError( null, "Env.shutdown(): " + e.toString(), e );
        } 
    } 
    
    
    /**
     * gibt fehlermeldung aus und beendet die VM
     */
    public void fatalError( Object sender, String msg, Exception e ) {
        logWriter.newEntry( sender, msg, e, LogWriter.ERROR );
        // FIXME: shutdown???
        System.exit( 1 );
    } 
    
    
    public int dbID() {
        return config.intProperty( Setup.DB_ID, -1 );
    } 
    
    
    public int portNum() {
        return config.intProperty( Setup.PORT, -1 );
    } 
    
    
    public int adminPortNum() {
        return config.intProperty( Setup.ADMIN_PORT, -1 );
    } 
    
    
    /**
     * Factory method to create or re-use a DR object.
     */
    public DeadlockRecognition deadlockRecognition() {
        if (dr == null) {
            dr = new EdgeChasing( this );
        } 
        return dr;
    } 
    
    
    public long nextID() {
        return nextID( 1 );
    } 
    
    
    public synchronized long nextID( long range ) {
        if (idCount + range >= idBorder) {
            try {
                idCount = state.longProperty( Setup.XOID, -1 );
                if (idCount == -1) {
                    throw new Exception( "Unable to create new ID number." );
                } 
                idBorder = idCount + range + idRange;
                state.setLongProperty( Setup.XOID, idBorder );
                state.notifyObservers();
            } catch (Exception e) {
                fatalError( null, "nextID(): " + e.toString(), e );
            } 
        } 
        long result = ++idCount;
        idCount += range;
        return result;
    } 
    
    
    /**
     * Initialize the internal memory counter so that freeMemory() returns
     * correct results.
     */
    protected void calcMemory() {
        logWriter.newEntry( this, "checking memory... ", LogWriter.INFO );
        
        Runtime rt = Runtime.getRuntime();
        try {
            DxBag bag = new DxArrayBag();
            for (;;) {
                bag.add( new byte[100000] );
            } 
        } catch (OutOfMemoryError e) {
            totalMemory = rt.totalMemory();
            rt.gc();
        } 
        
        logWriter.newEntry( this, "   total: " + totalMemory, LogWriter.INFO );
        logWriter.newEntry( this, "   free : " + rt.freeMemory(), LogWriter.INFO );
    } 
    
    
    /**
     * Return the amount of *total* free memory in the system. The results
     * returned by Runtime.freeMemory() may change overtime and so its
     * useless for ozone.
     */
    public long freeMemory() {
        Runtime rt = Runtime.getRuntime();
        long hiddenMemory = totalMemory - rt.totalMemory();
        
        // keep xMB free at least
        return Math.max( rt.freeMemory() + hiddenMemory - 4000000L, 0 );
    } 
    
}