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4.0 Preface

This is the manual for older MicroStream versions (Version < 5.0).

The new documentation (Version >= 5.0) is located at:

https://docs.microstream.one/

Welcome to the MicroStream Reference Manual. This manual includes concepts, instructions and examples to guide you on how to use MicroStream Data-Store and Cache, version 4.0.

You should be familiar with the Java programming language and you should have installed your preferred Integrated Development Environment (IDE). But since you are here we guest you got that covered ;)

What's new in 4.0

Changelog

API Docs

The API documentation is available at https://api.docs.microstream.one/4.0/.

Support

For information on the commercial support for MicroStream see microstream.one.

License

System Requirements

This is the manual for older MicroStream versions (Version < 5.0).

The new documentation (Version >= 5.0) is located at:

https://docs.microstream.one/

Supported JDKs

Tested and officially supported JDKs:

JDK	Supported Versions
	8, 11, 15
	8, 11, 15
	8, 11, 15
	8, 11, 14
	8, 11
	8, 11, 15
	8, 11, 15
	11, 15
	8, 11, 14
	20.0 +
	API level 26+

In theory MicroStream is compatible with all JDK distributions from Version 8 on.

Supported Operating Systems

Every desktop or server operating system which the supported JVMs are available for
Android 8+

Third Party Libraries

MicroStream's core itself doesn't have any dependencies to other libraries whatsoever. So you don't have to worry about potential conflicts in your environment. This was a matter of choice of ours to keep the life of the developers using MicroStream as simple as possible. On the other hand feel free to include any dependencies you need, MicroStream will play along well, e.g. a logging framework of your choice.

Data-Store

Getting Started

This is the manual for older MicroStream versions (Version < 5.0).

The new documentation (Version >= 5.0) is located at:

Prerequisites

Hello World

This simplest example will create a new storage if no existing storage is found, if a existing storage is found it will be loaded (this is all done at line 2 in the example above).

In line 6 the current storage's content is printed.

Line 7 assigns some data to the storage, replacing existing data if there is some.

In line 8 everything gets stored.

The Root Instance

When using MicroStream, your entire database is accessed starting at a root instance. This instance is the root object of an object graph that gets persisted by the MicroStream storage logic. While the root instance can be of any type (for example just a collection or an array), it is a good idea to define an explicit root type specific for the application. In this simple example, it is a class called DataRoot, which wraps a single String.

More about root instances:

Creating a Database

The following code is all that is required to setup a an application backed by a MicroStream database. The application's convenience root instance is defined and an EmbeddedStorageManager instance, linked to the root, is created (and its database managing threads are started). This is a fully operational Java database application.

Storing Data

This call is all that is necessary to store data in the simplest case.

Stopping a Live Database

Best practice is to safely shutdown the storage manager by simply calling:

storageManager.storeRoot() is a special case method that always stores the root object. If you want to store any other object than the root itself, just call storageManager.store(modifiedObject)

4.0

Preface

What's new in 4.0

API Docs

Support

License

System Requirements

Supported JDKs

Supported Operating Systems

Third Party Libraries

Data-Store

Getting Started

Prerequisites

Hello World

The Root Instance

Creating a Database

Storing Data

Stopping a Live Database

Cache

Basic Concepts