parserimplbase.java

java1.6众多例子参考

/*
 * @(#)ParserImplBase.java	1.20 05/11/17
 *
 * Copyright 2006 Sun Microsystems, Inc. All rights reserved.
 * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
package com.sun.corba.se.spi.orb ;

import java.util.Map ;
import java.util.Set ;
import java.util.Iterator ;
import java.util.Properties ;

import java.security.PrivilegedExceptionAction ;
import java.security.PrivilegedActionException ;
import java.security.AccessController ;

import java.lang.reflect.Field ;

import org.omg.CORBA.INTERNAL ;

import com.sun.corba.se.spi.logging.CORBALogDomains ;

import com.sun.corba.se.impl.logging.ORBUtilSystemException ;

import com.sun.corba.se.impl.orbutil.ObjectUtility ;

// XXX This could probably be further extended by using more reflection and
// a dynamic proxy that satisfies the interfaces that are inherited by the
// more derived class.  Do we want to go that far?
public abstract class ParserImplBase {
    private ORBUtilSystemException wrapper ;

    protected abstract PropertyParser makeParser() ;

    /** Override this method if there is some needed initialization
    * that takes place after argument parsing.  It is always called 
    * at the end of setFields.
    */
    protected void complete() 
    {
    }

    public ParserImplBase()
    {
	// Do nothing in this case: no parsing takes place
	wrapper = ORBUtilSystemException.get( 
	    CORBALogDomains.ORB_LIFECYCLE ) ;
    }

    public void init( DataCollector coll )
    {
	PropertyParser parser = makeParser() ;
	coll.setParser( parser ) ;
	Properties props = coll.getProperties() ;
	Map map = parser.parse( props ) ;
	setFields( map ) ;
    }

    private Field getAnyField( String name )
    {
	Field result = null ;

	try {
	    Class cls = this.getClass() ;
	    result = cls.getDeclaredField( name ) ;
	    while (result == null) {
		cls = cls.getSuperclass() ;
		if (cls == null)
		    break ;

		result = cls.getDeclaredField( name ) ;
	    }
	} catch (Exception exc) {
	    throw wrapper.fieldNotFound( exc, name ) ;
	}

	if (result == null)
	    throw wrapper.fieldNotFound( name ) ;

	return result ;
    }

    protected void setFields( Map map )
    {
	Set entries = map.entrySet() ;
	Iterator iter = entries.iterator() ;
	while (iter.hasNext()) {
	    java.util.Map.Entry entry = (java.util.Map.Entry)(iter.next()) ;
	    final String name = (String)(entry.getKey()) ;
	    final Object value = entry.getValue() ;

	    try {
		AccessController.doPrivileged( 
		    new PrivilegedExceptionAction() {
			public Object run() throws IllegalAccessException, 
			    IllegalArgumentException
			{
			    Field field = getAnyField( name ) ;
			    field.setAccessible( true ) ;
			    field.set( ParserImplBase.this, value ) ;
			    return null ;
			}
		    } 
		) ;
	    } catch (PrivilegedActionException exc) {
		// Since exc wraps the actual exception, use exc.getCause()
		// instead of exc.
		throw wrapper.errorSettingField( exc.getCause(), name,
		    ObjectUtility.compactObjectToString(value) ) ;
	    }
	}

	// Make sure that any extra initialization takes place after all the
	// fields are set from the map.
	complete() ;
    }
}