db4o-gpl: DB4O GPL 升级版本，支持最新.NETStandard Java Lambda Android Xamarin 等 ...

原作者: [db:作者] 来自: 网络收藏邀请

开源软件名称：

db4o-gpl

开源软件地址：

https://gitee.com/iboxdb/db4o-gpl

开源软件介绍：

The Basic Principle of db4o

db4o is a non-intrusive persistence system that stores any complex object with one single line of code. The class schema of your application classes is analysed and adjusted in real time when objects are stored. Object-oriented querying functionality is provided through Native Queries (NQ), the ability to query the database using .NET syntax and semantics (similar in concept to LINQ/DLINQ), Query by Example (QBE) which uses prototype objects for querying and other APIs. High performance is achieved with indexed fields and by reducing database-file-internal redirections to the absolute minimum. db4o features ACID transactions, fast embedded single-user mode and multi-transactional Client/Server access, locally and through TCP, object-oriented replication, and the ObjectManager to browse database files.

Download Object Manager Binaries to TRY

Db4o-GPL .NetStandard2.0 & Java7+ Version

Not as complexity as big SQL database server, not as simplicity as iBoxDB,

Db4o is the best database project to help you to learn how to write a database.

This adventurous oop-database project, has no news in a long time.here update it to .NetStandard2 & Java7. some users maybe need it.

DotNet Core

Use MonoDevelop to Open Db4o-2010.sln or run

Db4objects.Db4o.Optional/dotnet publish -c Releasetest/dotnet run

/test includes a dotnet core example.

JAVA 7

Use IDE NetBeans 11 to Open db4o.j/db4o-core project

 Build Project will output a jar to ../db4o-gpl/db4o.j/db4o-core/dist/db4o-core.jar or Run File, db4o.j/db4o-core/tutorial/src/com/db4odoc/f1/Main.java

Xamarin

Db4o-Projects/*/dotnet publish -c Release //like aboveAdd 4 DLLs in /Output to xamarin-projectvar path = Environment.GetFolderPath(Environment.SpecialFolder.Personal);string dbpath = Path.Combine(path, "x.db");db = Db4oEmbedded.OpenFile(dbpath);Project Properities->Android Options->Linking->"Sdk Assemblies Only" (not "Sdk and User Assemblies").Permission: Read/Write_External_Storage, INTERNET

Android Java

// <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>// <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>// <uses-permission android:name="android.permission.INTERNET"/>private class Async extends android.os.AsyncTask{  @Override    protected Object doInBackground(Object... arg) {    //Path     //android.os.Environment.getDataDirectory().getAbsolutePath()    //		+ "/data/" + "com.example.fapp" + ""    //DB4O Code here     return null;  }}new Async().execute(null);

Download Assemblies Directly

.NETStandard2

JAVA JAR

Nuget db4o-core

.NET Tutorials

Getting Started With db4o

gamlor.info

Object-oriented database programming with db4o

API

.NET Docs Db4oEmbedded

JAVA Docs Db4oEmbedded

About UpdateDepth

Examples

.NET Example

JAVA Example

WIKI

One Local Share Connection

ObjectContainer db = Db4oEmbedded.openFile(Db4oEmbedded				.newConfiguration(), DB4OFILENAME);

See Session Object Container

Multiple Local Connections

ServerConfiguration config = Db4oClientServer.newServerConfiguration();//https://iboxdb.github.io/db4o-gpl-doc/javadoc/com/db4o/config/CommonConfiguration.html#updateDepth(int)config.common().objectClass(Car.class).updateDepth(5);//https://iboxdb.github.io/db4o-gpl-doc/javadoc/com/db4o/cs/Db4oClientServer.html#openServer(com.db4o.cs.config.ServerConfiguration,java.lang.String,int)//Set Port = 0ObjectServer server = Db4oClientServer.openServer(config, DB4OFILENAME, 0);try {  ObjectContainer client = server.openClient();  // Do something with this clients  client.close();} finally {  server.close();}//Open new Client for every request. Concurrentpublic static void queryLocalServer(ObjectServer server) {  ObjectContainer client = server.openClient();  listResult(client.queryByExample(new Car("885588")));  client.close();}

Multiple Remote Connections

//set PORT > 0ObjectServer server = Db4oClientServer.openServer(Db4oClientServer				.newServerConfiguration(), DB4OFILENAME, PORT);server.grantAccess(USER, PASSWORD);try {  ObjectContainer client = Db4oClientServer.openClient(    Db4oClientServer.newClientConfiguration(), "localhost",PORT, USER, PASSWORD);  // Do something with this client, or open more clients  client.close();} finally {  server.close();}

Java Lambda Index

var rs = see.query((Record r) -> r.indexField == dv);

Lambda index. FieldName on the left, enable index; on the right, disable index.

Getting Started

public class Node{  [Indexed]  public String Name;  public Node Left;  public Node Right;}    StringBuilder sb = new StringBuilder();var path = Environment.GetFolderPath(Environment.SpecialFolder.Personal);path = Path.Combine(path, "t.db");File.Delete(path);var cf = Db4oEmbedded.NewConfiguration();cf.Common.Add(new TransparentActivationSupport());cf.Common.Add(new TransparentPersistenceSupport());using (var oc = Db4oEmbedded.OpenFile(cf, path)){    using (var ss = oc.Ext().OpenSession())    {        Node root = new Node();        root.Name = "Root";        root.Left = new Node();        root.Left.Name = "LEFT";        root.Left.Left = new Node();        root.Left.Left.Name = "LEFT.LEFT";        ss.Store(root);        ss.Commit();    }    using (var ss = oc.Ext().OpenSession())    {        sb.AppendLine(ss.QueryByExample(new Node { Name = "Root" }).First().Left.Left.Name);    }}

Object Management

Use NetBeans-11 with Java on Linux

build 'db4o.j/db4o-core' project, get db4o-core.jaruse NetBeans open db4o-gpl/admins/om.j/ObjectManager/ build and run

Use MonoDevelop-7.8.4+ with Mono-6 on Linux

Db4o-Projects/*/dotnet publish -c Release, get db4o DLLsuse MonoDevelop open  db4o-gpl/admins/om.net/OMAddin-2010.sln build and run

See the result, images/db4o_gpl.png

See the result, images/db4o_java_gpl.png

License: GPL , as MySQL.

The info from the author.http://supportservices.actian.com/versant/default.html

db4oWith regret we have to announce that Actian decided not to actively pursue and promote the commercial db4o product offering for new customers any longer.Since the db4o dual licensing model allows for the free usage of the community edition of db4o for non-commercial purposes, you have the opportunity to continue to use it for your non-commercial applications oreven fork it to provide support for the community.You can find the latest installer packages including the source tarball here for Java, .NET35, .NET40Actian will continue to provide commercial licenses and support for existing customers with active support contract.