The dotNet4Java is a .Net Runtime Library for Java which helps Java developers work with .Net framework and 3rd party libraries in Java with ease. It is designed to provide a way to interact with applications written in anyone of the .Net languages (such as C#, Visual Basic.Net, Delphi.Net, JScript.Net, etc) from Java.

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The easiest and the most efficient Java and .NET integration technology in the market. Our product helps software companies to integrate Java and .NET with the highest performance, reliability and flexibility to build the cross-technology web, desktop or server applications. dotNet4Java is the best native Java and .NET bridge on the market. Today's world is using two dominating software development platforms .NET and Java equally distributed across products and devices. dotNet4Java enables different industries to access broader markets with their products by exposing existing solutions for both technologies. For end-consumers dotNet4Java allows to share purchased products between .NET and Java teams or access critical modules and devices not available in the preferred technology.

dotNet4Java bridges between .NET and Java by working in a single process that makes it invisible to end-users. Working in a single process means both VMs are in the same process, so any call uses same thread and same stack for both environments.

dotNet4Java loads .Net CLR Native Interface library and bind it to Java JVM with native module which translates the calls from the interface to the methods on the Java JVM using JNA which automatically converts data-types, manages memory and threads synchronization and guarantees high performance, increased reliability and security.

We use JNA to register .NET implementation of native methods of .Net Native Interface Library to forward call to methods on real .NET objects.

What dotNet4Java can do:

  • Access .Net Framework Class Library (such as Collections, IO, Networking, Security, Cryptogrphy etc).
  • Access 3rd Party .Net Libraries.
  • Hosts the .Net Common Language Runtime (CLR) in Java.
  • Can load and access assemblies/types from 3rd party .Net libraries or executable files.
  • Can load and access .Net assemblies/types from Global Assembly Cache (GAC)
  • Can invoke members of a .Net types (such as constructor, fields, properties, methods and events).
  • Can create instance of .Net object.
  • Can handle .Net exceptions.
  • Can handle, access and invoke .Net events.
  • ...and many more.

Competitive Advantages

  • Full access to .Net Framework Class Library (Including new and emerging .NET technologies).
  • dotNet4Java is single jar file that can be very easily added to any type of Java project EJB, applet, desktop, console or service.
  • dotNet4Java JAR can be easily added to artefacts repository like maven or ivy.
  • No extra dll is required when deployed.
  • There is no configuration required and no external tools installation needed. Project can be moved shared across developer and build & test machines with just granting access to source code and transitioned to production within the main application archive.
  • Allows Java to consume .Net libraries as if they were native code.
  • When it comes to advanced libraries which use complex objects as method arguments, results, utilize event, callbacks and asynchronous invocation many alternatives become unacceptable whereas dotNet4Java starts to shine with intuitive and easy way of working with such objects almost like using single technology stack.
  • Lightweight and easy to use.
  • There are tools to import and generate .Net Libraries into Java class files.

Online Examples

Click button below to view source code examples on the usage of the dotNet4Java.

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Supported Platforms


Supported Java SE

  • Java SE 14
  • Java SE 13
  • Java SE 12
  • Java SE 11
  • Java SE 10
  • Java SE 9
  • Java SE 8


Supported .NET Framework

  • Support for .NET Framework 4.8
  • Support for .NET Framework 4.7
  • Support for .NET Framework 4.6
  • Support for .NET Framework 4.5


Supported Platforms

  • Windows OS 32-bit.
  • Windows OS 64-bit

Included Demos

These demos are installed with the product. Download the FREE trial to get started.

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Starting at $199.95

dotNet4Java provides a cost-effective solution for developers to
access .Net assemblies from Java.