Java AWT Native Interface (JAWT) is an interface for the

Java programming language Java is a high-level, general-purpose, memory-safe, object-oriented programming language. It is intended to let programmers ''write once, run anywhere'' ( WORA), meaning that compiled Java code can run on all platforms that support Jav ...

that enables rendering

libraries A library is a collection of Book, books, and possibly other Document, materials and Media (communication), media, that is accessible for use by its members and members of allied institutions. Libraries provide physical (hard copies) or electron ...

compiled to

native code In computer programming, machine code is computer program, computer code consisting of machine language instruction set architecture, instructions, which are used to control a computer's central processing unit (CPU). For conventional binary ...

to draw directly to a Java

Abstract Window Toolkit The Abstract Window Toolkit (AWT) is Java's original platform-dependent windowing, graphics, and user-interface widget toolkit, preceding Swing. The AWT is part of the Java Foundation Classes (JFC) — the standard API for providing a graphic ...

(AWT)

object Object may refer to: General meanings * Object (philosophy), a thing, being, or concept ** Object (abstract), an object which does not exist at any particular time or place ** Physical object, an identifiable collection of matter * Goal, an a ...

drawing surface. The

Java Native Interface The Java Native Interface (JNI) is a foreign function interface programming framework that enables Java code running in a Java virtual machine (JVM) to call and be called by native applications (programs specific to a hardware and operating s ...

(JNI) allows developers to add platform-dependent functionality to

Java Java is one of the Greater Sunda Islands in Indonesia. It is bordered by the Indian Ocean to the south and the Java Sea (a part of Pacific Ocean) to the north. With a population of 156.9 million people (including Madura) in mid 2024, proje ...

applications Application may refer to: Mathematics and computing * Application software, computer software designed to help the user to perform specific tasks ** Application layer, an abstraction layer that specifies protocols and interface methods used in a ...

. The JNI enables developers to add time-critical operations like

mathematical Mathematics is a field of study that discovers and organizes methods, Mathematical theory, theories and theorems that are developed and Mathematical proof, proved for the needs of empirical sciences and mathematics itself. There are many ar ...

calculations and

3D rendering 3D rendering is the 3D computer graphics process of converting 3D models into 2D images on a computer. 3D renders may include photorealistic effects or non-photorealistic styles. Rendering methods Rendering is the final process of creati ...

. Previously, native 3D rendering was challenging because the native code did not have access to the graphic context. The AWT Native Interface is designed to give developers access to an AWT Canvas for direct drawing with native code. In fact, the

Java 3D Java 3D is a scene graph-based 3D application programming interface (API) for the Java platform. It runs on top of either OpenGL or Direct3D until version 1.6.0, which runs on top of Java OpenGL (JOGL). Since version 1.2, Java 3D has been dev ...

API extension to the standard

Java SE Java Platform, Standard Edition (Java SE) is a computing platform for development and deployment of portable code for desktop and server environments. Java SE was formerly known as Java 2 Platform, Standard Edition (J2SE). The platform uses th ...

JDK relies heavily on the AWT Native Interface to render 3D objects in Java. The AWT Native Interface is very similar to the JNI, and the steps are the same as those of the JNI. See the

article for an explanation of the JNI techniques employed by the AWT Native Interface. The AWT Native Interface was added to the

Java platform Java is a set of computer software and specifications that provides a software platform for developing application software and deploying it in a cross-platform computing environment. Java is used in a wide variety of computing platforms fr ...

with the J2SE 1.3 ("Kestrel") version.

Native painting

One can paint as if it is a native application. In

Windows Windows is a Product lining, product line of Proprietary software, proprietary graphical user interface, graphical operating systems developed and marketed by Microsoft. It is grouped into families and subfamilies that cater to particular sec ...

, the JVM will pass a HWND and other window information to the native application so that the application will "know" where to draw. It could use GDI to draw a Rectangle. The window information the native side needs will be in a JAWT_Win32DrawingSurfaceInfo structure (depending on the

operating system An operating system (OS) is system software that manages computer hardware and software resources, and provides common daemon (computing), services for computer programs. Time-sharing operating systems scheduler (computing), schedule tasks for ...

) which can be retrieved with this line:

References

External links

The AWT Native Interface
{{Java desktop AWT Native Interface