dxexception.java

Java的面向对象数据库系统的源代码

// You can redistribute this software and/or modify it under the terms of
// the Ozone Library License version 1 published by ozone-db.org.
//
// The original code and portions created by SMB are
// Copyright (C) 1997-@year@ by SMB GmbH. All rights reserved.
//
// $Id: DxException.java,v 1.1 2001/12/18 10:31:30 per_nyfelt Exp $

package org.ozoneDB.DxLib;

import java.lang.reflect.*;
import java.io.*;

/**
 * Diese Klasse dient dazu, ein Java-Exception in einem Stream zu schreiben
 * bzw. daraus zu lesen. Das ist z.B. fuer Socket-Verbindungen nuetzlich.
 *
 *
 * @author <a href="http://www.softwarebuero.de/">SMB</a>
 * @version $Revision: 1.1 $Date: 2001/12/18 10:31:30 $
 */
public class DxException extends DxObject implements Externalizable {

    final static long serialVersionUID = 1L;

    Throwable exc;
    String msg;


    public DxException() {
        msg = new String();
    }


    public DxException( Throwable e ) {
        exc = e;
        msg = new String( e.toString() );
    }


    public Throwable toExc() {
        return exc;
    }


    public String toString() {
        return msg;
    }


    public void writeExternal( ObjectOutput out ) throws IOException {
        try {
            if (exc != null) {
                out.writeUTF( exc.getClass().getName() );
            } else {
                out.writeUTF( "null" );
            }
            out.writeUTF( msg );
        } catch (Exception e) {
            throw new IOException( e.toString() );
        }
    }


    public void readExternal( ObjectInput in ) throws IOException {
        try {
            String e = in.readUTF();
            msg = in.readUTF();
            if (e.compareTo( "null" ) != 0) {
                Class[] classes = new Class[1];
                classes[0] = e.getClass();

                //Constructor constr = Class.forName( e ).getConstructor( classes );
                // todo: uncommented until verified that it works
                // todo: maybe we should use ClassManager here instead ot Thread.currentThread...?
                Constructor constr = Thread.currentThread().getContextClassLoader().loadClass( e ).getConstructor( classes );

                if (constr != null) {
                    Object[] args = new Object[1];
                    args[0] = msg;
                    System.out.println( args[0] );
                    exc = (Throwable)constr.newInstance( args );
                }
            }
        } catch (Exception e) {
            throw new IOException( e.toString() );
        }
    }
}