groupimpl.java

用Java写的面相对象的数据库管理系统

// 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) 1997-2000 by SMB GmbH. All rights reserved.
//
// $Id: GroupImpl.java,v 1.4 2000/10/28 16:55:20 daniela Exp $

package org.ozoneDB.test.tx;

import java.io.*;
import org.ozoneDB.*;
import org.ozoneDB.DxLib.*;


public class GroupImpl extends OzoneObject implements Group {
    
    protected final static long serialVersionUID = 1;
    
    protected String name;
    
    protected DxHashMap users;
    
    
    public GroupImpl() {
        name = "Group";
        users = new DxHashMap();
    }
    
    
    public void setName( String _name ) {
        name = _name;
    } 
    
    
    public String name() {
        return name;
    } 
    
    
    public User[] getAll() {
        System.out.println( "*** getAll():" );
        
        User[] result = new User[users.count()];
        DxIterator it = users.iterator();
        for (int i = 0; it.next() != null; i++) {
            result[i] = (User)it.object();
        } 
        return result;
    
    // return (User[])users.toArray();
    } 
    
    
    public void addUser( User user ) throws Exception {
        users.addForKey( user, user.name() );
    } 
    
    
    public void populate( int n ) throws Exception {
        for (int i = 0; i < n; i++) {
            User user = (User)database().createObject( UserImpl.class.getName() );
            users.addForKey( user, user.name() );
        } 
    } 
    
    
    public void crash() {
        throw new NullPointerException();
    } 
    
    
    public String toString() {
        return "Group: name=" + name + ", userCount=" + users.count();
    } 
    
    
    public void done() throws Exception {
        DxIterator it = users.iterator();
        while (it.next() != null) {
            database().deleteObject( (User)it.object() );
        } 
    } 
}