[Android] 解析android framework下利用app_process来调用java写的命令及示例

public final class strongcmd {
    static final String TAG = "strong";
    static String[] mArgs;
    int mNextArg;
        
    public static void main(String[] args) {
        printUsage();
        System.err.println("Wellcom strong test function!!");
        try {
            new strongcmd().run();
        } catch (Exception e) {
            System.err.println("Unable to run settings command");
        }
    }

    public void run() {
        try {
            System.err.println("Now strong run() again");
        } catch (Exception e) {
            System.err.println("Now strong run() Exception");
        }
    }

    private static void printUsage() {
        System.err.println("usage: strong -a -b -h");
        System.err.println("'a' is for add");
        System.err.println("-h for help");
    }
}

    LOCAL_PATH:= $(call my-dir)
　　include $(CLEAR_VARS)
　　LOCAL_SRC_FILES := $(call all-subdir-java-files)
　　LOCAL_MODULE := strong
　　LOCAL_MODULE_TAGS := optional
　　include $(BUILD_JAVA_LIBRARY)
　　include $(CLEAR_VARS)
　　LOCAL_MODULE := strong
　　LOCAL_SRC_FILES := pre_strong
　　LOCAL_MODULE_CLASS := EXECUTABLES
　　LOCAL_MODULE_TAGS := optional
　　include $(BUILD_PREBUILT) 

base=/system
export CLASSPATH=$base/framework/strong.jar
exec app_process $base/bin com.android.commands.strong.strongcmd "$@"

virtual void onVmCreated(JNIEnv*env) {
        if (mClassName == NULL) {
            return; // Zygote. Nothing to do here.
        }
        /*
    * This is a little awkward because the JNI FindClass call uses the
    * class loader associated with the native method we're executing in.
    * If called in onStarted (from RuntimeInit.finishInit because we're
    * launching "am", for example), FindClass would see that we're calling
    * from a boot class' native method, and so wouldn't look for the class
    * we're trying to look up in CLASSPATH. Unfortunately it needs to,
    * because the "am" classes are not boot classes.
    *
    * The easiest fix is to call FindClass here, early on before we start
    * executing boot class Java code and thereby deny ourselves access to
    * non-boot classes.
    */
        char*slashClassName = toSlashClassName(mClassName);
        mClass = env -> FindClass(slashClassName);
        if (mClass == NULL) {
            ALOGE("ERROR: could not find class '%s'\n", mClassName);
        }
        free(slashClassName);
        mClass = reinterpret_cast(env -> NewGlobalRef(mClass));
    }

    virtual void onStarted() {
        sp proc = ProcessState::self ();
        ALOGV("App process: starting thread pool.\n");
        proc -> startThreadPool();
        AndroidRuntime * ar = AndroidRuntime::getRuntime ();
        ar -> callMain(mClassName, mClass, mArgC, mArgV);
        IPCThreadState::self () -> stopProcess();
    }

    className) {
        // Remainder of args get passed to startup class main()
        runtime.mClassName = className;
        runtime.mArgC = argc - i;
        runtime.mArgV = argv + i;
        runtime.start("com.android.internal.os.RuntimeInit",
                application ? "application" : "tool");
    }