Compilation of AST By Adding it to CompilationUnits

[Daisy Smith]

Hello everyone,

I have a file(GeneratedClass.java) which is in AST form and I want it to get picked up by javac for compilation. I have tried to add the file to the compilation units and then let javac do the rest but I get NullPointerExceptions. Here is the code:

    /*
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    package myclass;

    import com.sun.tools.javac.main.JavaCompiler;
    import com.sun.tools.javac.tree.JCTree;
    import com.sun.tools.javac.tree.JCTree.JCCompilationUnit;
    import com.sun.tools.javac.util.Context;
    import java.io.IOException;
    import java.util.Locale;
    import java.util.logging.Level;
    import java.util.logging.Logger;
    import javax.tools.JavaFileObject;
    import static javax.tools.JavaFileObject.Kind.SOURCE;
    import javax.tools.StandardJavaFileManager;
    import static javax.tools.StandardLocation.SOURCE_PATH;
    import javax.tools.ToolProvider;

    /**
     *
     * @author guestu
     */
    public class MyClass extends JavaCompiler {

        public static Context contexts = new Context();

        public static void main(String[] args) {
          
            try {
                                
                javax.tools.JavaCompiler compiler = 
                    ToolProvider.getSystemJavaCompiler();
                
                StandardJavaFileManager stdFileManager = 
                    compiler.getStandardFileManager(null, Locale.getDefault(), null);
                                
                JavaFileObject compilationUnits = 
                    stdFileManager.getJavaFileForInput(SOURCE_PATH, "GeneratedClass", SOURCE);
                                
                MyClass cy = new MyClass(contexts);
                
                cy.parse(compilationUnits); //line 47
                
            } catch (IOException ex) {
                System.out.println("Exception thrown  :" + ex);
                Logger.getLogger(MyClass.class.getName()).log(Level.SEVERE, null, ex);
            }                      
        }

        public MyClass(Context cntxt) {
            super(cntxt);
        }     

        @Override
        public JCTree.JCCompilationUnit parse(JavaFileObject filename){
            return super.parse(filename);  //line 57
        }     

        @Override
        protected JCCompilationUnit parse(JavaFileObject filename, CharSequence readSource) {

                return super.parse(filename, readSource);
        }  
    }

Here is the stacktrace produced:

run:
Exception in thread "main" java.lang.NullPointerException
	at com.sun.tools.javac.main.JavaCompiler.readSource(JavaCompiler.java:571)
	at com.sun.tools.javac.main.JavaCompiler.parse(JavaCompiler.java:632)
	at myclass.MyClass.parse(MyClass.java:57)
	at myclass.MyClass.main(MyClass.java:47)
Java Result: 1
BUILD SUCCESSFUL (total time: 1 second)

I think the culprit is in the line

 JavaFileObject compilationUnits = 
                    stdFileManager.getJavaFileForInput(SOURCE_PATH, "GeneratedClass", SOURCE);

but I can't be too sure. The path to GeneratedClass.java is /home/guestu/GeneratedClass.java
Thanks for the time.