Android Question how can i call a (MAIN)method from b4a to jar

The method name is main not MAIN.

i also try with main,but can't do ,can you try?

class1=ClassLoader.getSystemClassLoader().loadClass("com.sun.tools.javac.Main");
Class[] argTypes = new Class[] { String[].class };
String[] mainArgs = {File1};
Method method=class1.getDeclaredMethod("main",argTypes);
method.invoke(class1.newInstance(),(Object)mainArgs);

in windows ,i add tools.jar(jdk file path),it can Compile abc.java to abc.class ,only one args,can it doing on ANDROIS?

I'm sorry but I don't understand what you are trying to do.

tools.jar is not an Android library. It will not work from an Android app.