codecfactoryimpl.java

java1.6众多例子参考

/*
 * @(#)CodecFactoryImpl.java	1.16 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.impl.interceptors;

import org.omg.IOP.Codec;
import org.omg.IOP.CodecFactory;
import org.omg.IOP.CodecFactoryPackage.UnknownEncoding;
import org.omg.IOP.Encoding;
import org.omg.IOP.ENCODING_CDR_ENCAPS;

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

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

import org.omg.CORBA.ORB;
import org.omg.CORBA.LocalObject;

/**
 * CodecFactoryImpl is the implementation of the Codec Factory, as described
 * in orbos/99-12-02.  
 */
public final class CodecFactoryImpl 
    extends org.omg.CORBA.LocalObject
    implements CodecFactory 
{
    // The ORB that created this Codec Factory
    private ORB orb;
    private ORBUtilSystemException wrapper ;

    // The maximum minor version of GIOP supported by this codec factory.
    // Currently, this is 1.2.
    private static final int MAX_MINOR_VERSION_SUPPORTED = 2;

    // The pre-created minor versions of Codec version 1.0, 1.1, ...,
    // 1.(MAX_MINOR_VERSION_SUPPORTED)
    private Codec codecs[] = new Codec[MAX_MINOR_VERSION_SUPPORTED + 1];

    /**
     * Creates a new CodecFactory implementation.  Stores the ORB that
     * created this factory, for later use by the Codec.
     */
    public CodecFactoryImpl( ORB orb ) {
        this.orb = orb;
	wrapper = ORBUtilSystemException.get( 
	    (com.sun.corba.se.spi.orb.ORB)orb, 
	    CORBALogDomains.RPC_PROTOCOL ) ;

	// Precreate a codec for version 1.0 through 
	// 1.(MAX_MINOR_VERSION_SUPPORTED).  This can be
	// done since Codecs are immutable in their current implementation.
	// This is an optimization that eliminates the overhead of creating
	// a new Codec each time create_codec is called.
	for( int minor = 0; minor <= MAX_MINOR_VERSION_SUPPORTED; minor++ ) {
	    codecs[minor] = new CDREncapsCodec( orb, 1, minor );
        }
    }

    /**
     * Creates a codec of the given encoding.  The only format recognized
     * by this factory is ENCODING_CDR_ENCAPS, versions 1.0 through 
     * 1.(MAX_MINOR_VERSION_SUPPORTED).
     *
     * @exception UnknownEncoding Thrown if this factory cannot create a 
     *   Codec of the given encoding.
     */
    public Codec create_codec ( Encoding enc ) 
        throws UnknownEncoding 
    {
        if( enc == null ) nullParam();

	Codec result = null;

	// This is the only format we can currently create codecs for:
	if( (enc.format == ENCODING_CDR_ENCAPS.value) &&
            (enc.major_version == 1) ) 
        {
	    if( (enc.minor_version >= 0) && 
		(enc.minor_version <= MAX_MINOR_VERSION_SUPPORTED) ) 
            {
		result = codecs[enc.minor_version];
	    }
	}

	if( result == null ) {
	    throw new UnknownEncoding();
	}

	return result;
    }

    /**
     * Called when an invalid null parameter was passed.  Throws a
     * BAD_PARAM with a minor code of 1
     */
    private void nullParam() 
    {
	throw wrapper.nullParam() ;
    }
}