c3p0config.java

c3p0数据库连接池实现源码

/*
 * Distributed as part of c3p0 v.0.9.1-pre6
 *
 * Copyright (C) 2005 Machinery For Change, Inc.
 *
 * Author: Steve Waldman <[e-mail]>
 *
 * This library is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License version 2.1, as 
 * published by the Free Software Foundation.
 *
 * This software is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this software; see the file LICENSE.  If not, write to the
 * Free Software Foundation, Inc., 59 Temple Place, Suite 330,
 * Boston, MA 02111-1307, USA.
 */


package com.mchange.v2.c3p0.cfg;

import java.beans.*;
import java.util.*;
import com.mchange.v2.c3p0.impl.*;
import com.mchange.v2.beans.*;
import com.mchange.v2.cfg.*;
import com.mchange.v2.log.*;

import java.io.IOException;
import java.lang.reflect.Method;
import com.mchange.v1.lang.BooleanUtils;

//all internal maps should be HashMaps (the implementation presumes HashMaps)

public final class C3P0Config
{
    public final static String CFG_FINDER_CLASSNAME_KEY = "com.mchange.v2.c3p0.cfg.finder";

    public final static String DEFAULT_CONFIG_NAME = "default";

    public final static C3P0Config MAIN;

    final static MLogger logger = MLog.getLogger( C3P0Config.class );

    static
    {
// 	Set knownProps = new HashSet();
// 	knownProps.add("acquireIncrement");
// 	knownProps.add("acquireRetryAttempts");
// 	knownProps.add("acquireRetryDelay");
// 	knownProps.add("autoCommitOnClose");
// 	knownProps.add("automaticTestTable");
// 	knownProps.add("breakAfterAcqireFailure");
// 	knownProps.add("checkoutTimeout");
// 	knownProps.add("connectionTesterClassName");
// 	knownProps.add("factoryClassLocation");
// 	knownProps.add("forceIgnoreUnresolvedTransactions");
// 	knownProps.add("idleConnectionTestPeriod");
// 	knownProps.add("initialPoolSize");
// 	knownProps.add("maxIdleTime");
// 	knownProps.add("maxPoolSize");

	C3P0Config protoMain;

	String cname = MultiPropertiesConfig.readVmConfig().getProperty( CFG_FINDER_CLASSNAME_KEY );

	C3P0ConfigFinder cfgFinder = null;
	try
	    {
		if (cname != null)
		    cfgFinder = (C3P0ConfigFinder) Class.forName( cname ).newInstance();
		
	    }
	catch (Exception e)
	    {
		if ( logger.isLoggable(MLevel.WARNING) )
		    logger.log( MLevel.WARNING, "Could not load specified C3P0ConfigFinder class'" + cname + "'.", e);
	    }
	if (cfgFinder == null)
	    cfgFinder = new DefaultC3P0ConfigFinder();
	try
	    { protoMain = cfgFinder.findConfig(); }
	catch (Exception e)
	    { 
		
		if ( logger.isLoggable(MLevel.WARNING) )
		    logger.log( MLevel.WARNING, "An Exception occurred while loading C3P0Config.", e);

		HashMap flatDefaults = C3P0ConfigUtils.extractHardcodedC3P0Defaults();
		flatDefaults.putAll( C3P0ConfigUtils.extractC3P0PropertiesResources() );
		protoMain = C3P0ConfigUtils.configFromFlatDefaults( flatDefaults );
	    }
	MAIN = protoMain;

	warnOnUnknownProperties( MAIN );
    }

    private static void warnOnUnknownProperties( C3P0Config cfg )
    {
	warnOnUnknownProperties( cfg.defaultConfig );
	for (Iterator ii = cfg.configNamesToNamedScopes.values().iterator(); ii.hasNext(); )
	    warnOnUnknownProperties( (NamedScope) ii.next() );
    }

    private static void warnOnUnknownProperties( NamedScope scope )
    {
	warnOnUnknownProperties( scope.props );
	for (Iterator ii = scope.userNamesToOverrides.values().iterator(); ii.hasNext(); )
	    warnOnUnknownProperties( (Map) ii.next() );
    }

    private static void warnOnUnknownProperties( Map propMap )
    {
	for (Iterator ii = propMap.keySet().iterator(); ii.hasNext(); )
	    {
		String prop = (String) ii.next();
		if (! C3P0Defaults.isKnownProperty( prop ) && logger.isLoggable( MLevel.WARNING ))
		    logger.log( MLevel.WARNING, "Unknown c3p0-config property: " + prop);
	    }
    }

    public static String getUnspecifiedUserProperty( String propKey, String configName )
    {
	  String out = null;

 	  if (configName == null)
	      out = (String) MAIN.defaultConfig.props.get( propKey );
	  else
	      {
		  NamedScope named = (NamedScope) MAIN.configNamesToNamedScopes.get( configName );
		  if (named != null)
		      out = (String) named.props.get(propKey);
		  else
		      logger.warning("named-config with name '" + configName + "' does not exist. Using default-config for property '" + propKey + "'.");

		  if (out == null)
		      out = (String) MAIN.defaultConfig.props.get( propKey );
	      }
	  
	  return out;
    }

    public static Map getUnspecifiedUserProperties(String configName)
    {
	Map out = new HashMap();

	out.putAll( MAIN.defaultConfig.props );

	if (configName != null)
	    {
		  NamedScope named = (NamedScope) MAIN.configNamesToNamedScopes.get( configName );
		  if (named != null)
		      out.putAll( named.props );
		  else
		      logger.warning("named-config with name '" + configName + "' does not exist. Using default-config.");
	    }

	return out;
    }

    public static Map getUserOverrides( String configName )
    {
	Map out = new HashMap();

	NamedScope namedConfigScope = null;

	if (configName != null)
	    namedConfigScope = (NamedScope) MAIN.configNamesToNamedScopes.get( configName );

	out.putAll( MAIN.defaultConfig.userNamesToOverrides );

	if (namedConfigScope != null)
	    out.putAll( namedConfigScope.userNamesToOverrides );

	return (out.isEmpty() ? null : out );
    }

    public static String getUserOverridesAsString(String configName) throws IOException
    {
	Map userOverrides = getUserOverrides( configName );
	if (userOverrides == null)
	    return null;
	else
	    return C3P0ImplUtils.createUserOverridesAsString( userOverrides ).intern();
    }

    final static Class[] SUOAS_ARGS = new Class[] { String.class };

    final static Collection SKIP_BIND_PROPS = Arrays.asList( new String[] {"loginTimeout", "properties"} );

    public static void bindNamedConfigToBean(Object bean, String configName) throws IntrospectionException
    {
	Map defaultUserProps = C3P0Config.getUnspecifiedUserProperties( configName );
	BeansUtils.overwriteAccessiblePropertiesFromMap( defaultUserProps, 
							 bean, 
							 false, 
							 SKIP_BIND_PROPS,
							 true,
							 MLevel.FINEST,
							 MLevel.WARNING,
							 false);
	try
	    {
		Method m = bean.getClass().getMethod( "setUserOverridesAsString", SUOAS_ARGS );
		m.invoke( bean, new Object[] {getUserOverridesAsString( configName )} );
	    }
	catch (NoSuchMethodException e)
	    {
		e.printStackTrace();
		/* ignore */ 
	    }
	catch (Exception e)
	    {
		if (logger.isLoggable( MLevel.WARNING ))
		    logger.log( MLevel.WARNING, 
				"An exception occurred while trying to bind user overrides " +
				"for named config '" + configName + "'. Only default user configs " +
				"will be used."
				, e);
	    }
    }

    /*
     *  Note that on initialization of a DataSource, no config name is known.
     *  We initialize local vars using the default config. The DataSources class
     *  and/or constructors that accept a configName then overwrite the initial
     *  values with namedConfig overrides if supplied.
     */
    public static String initializeUserOverridesAsString()
    {
	try
	    { return getUserOverridesAsString( null ); }
	catch (Exception e)
	    {
		if (logger.isLoggable( MLevel.WARNING ))
		    logger.log( MLevel.WARNING, "Error initializing default user overrides. User overrides may be ignored.", e);
		return null;
	    }
    }

    public static String initializeStringPropertyVar(String propKey, String dflt)
    {
	String out = getUnspecifiedUserProperty( propKey, null );
	if (out == null) out = dflt;
	return out;
    }

    public static int initializeIntPropertyVar(String propKey, int dflt)
    {
	boolean set = false;
	int out = -1;

	String outStr = getUnspecifiedUserProperty( propKey, null );
	if (outStr != null)
	    {
		try 
		    { 
			out = Integer.parseInt( outStr.trim() ); 
			set = true;
		    }
		catch (NumberFormatException e)
		    {
			logger.info("'" + outStr + "' is not a legal value for property '" + propKey +
				    "'. Using default value: " + dflt);
		    }
	    }

	if (!set)
	    out = dflt;

	//System.err.println("initializing " + propKey + " to " + out);
	return out;
    }

    public static boolean initializeBooleanPropertyVar(String propKey, boolean dflt)
    {
	boolean set = false;
	boolean out = false;

	String outStr = getUnspecifiedUserProperty( propKey, null );
	if (outStr != null)
	    {
		try 
		    { 
			out = BooleanUtils.parseBoolean( outStr.trim() ); 
			set = true;
		    }
		catch (IllegalArgumentException e)
		    {
			logger.info("'" + outStr + "' is not a legal value for property '" + propKey +
				    "'. Using default value: " + dflt);
		    }
	    }

	if (!set)
	    out = dflt;

	return out;
    }



    NamedScope defaultConfig;
    HashMap configNamesToNamedScopes;

    C3P0Config( NamedScope defaultConfig, HashMap configNamesToNamedScopes)
    {
	this.defaultConfig = defaultConfig;
	this.configNamesToNamedScopes = configNamesToNamedScopes;
    }

}