[转]phoneME Advanced Peer File Structure

For those interested in creating a phoneME Advanced implementation on other platforms with other windowing toolkits, you may be wondering how and where to start. The first thing you'll want to do is get the CDC VM (CVM) up and running. I won't go into detail about this, but an important point to note is that the CDC (Connected Device Configuration) specifies a set of Java classes that must be present. Besides porting the VM itself, the CDC classes also need to be ported. This, however, should be fairly straightforward. The bulk of the CDC Java code, which is usable across platforms, is in the src/share/classes directory. These Java classes require support of the underlying native code which interfaces with the OS of choice directly. The bulk of the CDC native code can be found in the src/share/native directory. For example, if you look at src/share/classes/java/lang/Object.java, it makes a native call (public final native Class getClass();) which is serviced by src/share/native/java/lang/Object.c. The files in the src/share directory are shared by all implementations, regardless of the hardware/OS. If there are special requirements by the hardware/OS which cannot be serviced by a shared file, you'll find files in src/os<-cpu>. For example, separate code is required to interface with the audio device in Personal Profile. So you'll find audioDevice.c in these places:

• src/darwin/personal/native/sun/audio/audioDevice.c

• src/linux/personal/native/sun/audio/audioDevice.c

• src/win32/personal/native/sun/audio/audioDevice.c

• src/solaris/personal/native/sun/audio/audioDevice.c

The good news is that, as previously stated in this article, the code which is NOT in the shared area is minimized as much as is possible.

Once we get above the configuration to the profiles, things become easier. Sitting atop CDC is the Foundation Profile (FP). Almost all of the code for implementing the FP is in the src/share/foundation directory. And just like the CDC code, there is a src/share/foundation/classes directory for Java code and a src/share/foundation/native directory for the native code which is called by the Java code. There are some files in the src/os<-cpu> directory which support the Foundation Profile. For example, the native PlainSocketImpl_md.c file which supports FP's SocketImpl.java class can be found in the src/os- directories.

Above the FP lies the Personal Basis Profile (PBP). Things get a little more complicated here as the PBP adds windowing code in the form of the Abstract Window Toolkit (AWT). This complicates things because there are different windowing toolkits on different platforms (and even on the same platform!) which can be used. Fortunately, however, the PBP code is isolated to the src/share/basis directory. Again, the common src/share/basis/classes directory contains the Java code and the src/share/basis/native directory contains the supporting native code. If you look in the src/share/basis/classes/awt directory, you'll see the Java classes which support the and UI toolkits under the microwindows and qt directories respectively. And of course, under src/share/basis/native/awt are also the microwindows and qt directories containing the supporting native code. The code in these native directories interact directly with the microwindows and qt libraries. This, plus the corresponding Java code is the “porting” layer for PBP.

Above the PBP sits the Personal Profile (PP). PP is a bit different in that it re-implements some of the classes in its underlying layer (PBP). For example, you'll find an AWTEvent.java and Graphics.java file in both PBP and PP. This is necessary to support the differences in PP. PP has yet a different directory structure from PBP underneath. You'll notice in the src/share/personal/classes directory, a directory named common. This directory contains Java classes which are common to the varying PP implementations. For example, there is a file named src/share/personal/classes/common/java/awt/GraphicsDevice.java. The various PP implementations have a GraphicsDevice class of their own which extends this common GraphicsDevice class. There is also an awt directory which contains a peer_based directory. Underneath this is a directory (java/awt) containing files common to all the peer-based PP implementations. The specific peer-based implementations are in the sun/awt/ directories. There, you'll find qt, gtk, and pocketpc implementations.