DB4O 封装(面向对象数据库)，采用泛型，支持任意对象存取，可移植性贼好！ 哈哈

自己封装的DB4O Template, 可很方便的进行对象保存，更新，级联更新及删除！ 废话不多说， 自己看源码：

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/**

?* DB4OUtils.java

?* com.dzg.ticket.util

?*

?* ? ver ? ? date ? ? ? author

?* ──────────────────────────────────

?* ? 2012-2-10 Administrator

?*

?* Copyright (c) 2012, TNT All Rights Reserved.

*/

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package utils;

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import java.io.IOException;

import java.net.URL;

import java.net.URLDecoder;

import java.util.ArrayList;

import java.util.List;

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import com.db4o.Db4oEmbedded;

import com.db4o.ObjectContainer;

import com.db4o.ObjectSet;

import com.db4o.config.EmbeddedConfiguration;

import com.db4o.query.Predicate;

//import com.dzg.ticket.bo.Passenger;

//import com.dzg.ticket.bo.Ticket;

//import com.dzg.ticket.bo.User;

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/**

?* ClassName:DB4OUtils

?* Copyright: copyright (c)2012

?* @author ? Deng Zhiguang

?* @Date 2012-2-10

?* Email: dengzhiguang@gmail.com

?* Modification History:

?* Date ? ? ?Author ? ? ?Version ? ?Reason

?* ------------------------------------------

?*/

public class DB4OTemplate {

private final static String DB4O_FILE_PATH = getClassPath() + "/db.yap";

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private static String getClassPath() {

URL url = DB4OTemplate.class.getResource("/");

String path = null;

try {

path = URLDecoder.decode(url.getPath(), "UTF-8");

} catch (IOException e) {

e.printStackTrace();

}

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return path;

}

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private static void cascadeClasses(EmbeddedConfiguration configuration, List<Class<?>> classList) {

for (Class<?> c : classList) {

configuration.common().objectClass(c).cascadeOnUpdate(true);

configuration.common().objectClass(c).cascadeOnDelete(true);

}

}

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public static <T> List<T> queryByExample(T t) {

List<T> result = new ArrayList<T>();

ObjectContainer db = null;

try {

db = Db4oEmbedded.openFile(DB4O_FILE_PATH);

ObjectSet<T> oSet = db.queryByExample(t);

while (oSet.hasNext()) {

result.add(oSet.next());

}

return result;

} finally {

if (db != null)

db.close();

}

}

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public static <T&