examples/Mini/MiniC.java

package Mini;
import java.util.Vector;
import java.io.*;
import org.apache.bcel.classfile.*;
import org.apache.bcel.generic.*;

public class MiniC implements org.apache.bcel.Constants {
  private static Vector errors   = null;
  private static Vector warnings = null;
  private static String file     = null;
  private static int   pass      = 0;
	
  public static void main(String[] argv) {
    String[]   file_name = new String[argv.length];
    int        files=0;
    MiniParser parser=null;
    String     base_name=null;
    boolean    byte_code=true;

    try {
      /* Parse command line arguments.
       */
      for(int i=0; i < argv.length; i++) {
	if(argv[i].charAt(0) == '-') {  // command line switch
	  if(argv[i].equals("-java"))
	    byte_code=false;
	  else if(argv[i].equals("-bytecode"))
	    byte_code=true;
	  else
	    throw new Exception("Unknown option: " + argv[i]);
	}
	else { // add file name to list
	  file_name[files++] = argv[i];
	}
      }
	
      if(files == 0)
	System.err.println("Nothing to compile.");

      for(int j=0; j < files; j++) {
	errors   = new Vector();
	warnings = new Vector();
	pass     = 0;

	if(j == 0)
	  parser = new MiniParser(new java.io.FileInputStream(file_name[0]));
	else
	  parser.ReInit(new java.io.FileInputStream(file_name[j]));

	int index = file_name[j].lastIndexOf('.');
	if(index > 0)
	  base_name = file_name[j].substring(0, index);
	else
	  base_name = file_name[j];

	if((index = base_name.lastIndexOf(File.separatorChar)) > 0)
	  base_name = base_name.substring(index + 1);

	file   = file_name[j];

	System.out.println("Parsing ...");
        parser.Program();
        ASTProgram program = (ASTProgram)parser.jjtree.rootNode();

	System.out.println("Pass 1: Optimizing parse tree ...");
        pass    = 1;
        program = program.traverse();
        // program.dump(">");

	if(errors.size() == 0) {
	  System.out.println("Pass 2: Type checking (I) ...");
	  program.eval(pass=2);
	}

	if(errors.size() == 0) {
	  System.out.println("Pass 3: Type checking (II) ...");
	  program.eval(pass=3);
	}

        for(int i=0; i < errors.size(); i++)
	  System.out.println(errors.elementAt(i));

        for(int i=0; i < warnings.size(); i++)
 	  System.out.println(warnings.elementAt(i));

	if(errors.size() == 0) {
	  if(byte_code) {
	    System.out.println("Pass 5: Generating byte code ...");
	    ClassGen class_gen = new ClassGen(base_name, "java.lang.Object",
					      file_name[j],
					      ACC_PUBLIC | ACC_FINAL |
					      ACC_SUPER, null);
	    ConstantPoolGen cp = class_gen.getConstantPool();

	    program.byte_code(class_gen, cp);
	    JavaClass clazz = class_gen.getJavaClass();
	    clazz.dump(base_name + ".class");
	  }
	  else {
	    System.out.println("Pass 5: Generating Java code ...");
	    PrintWriter out = new PrintWriter(new FileOutputStream(base_name + ".java"));
	    program.code(out, base_name);
	    out.close();

	    System.out.println("Pass 6: Compiling Java code ...");

	    String[] args = { "javac", base_name + ".java" };
	    //sun.tools.javac.Main compiler = new sun.tools.javac.Main(System.err, "javac");
	    try {
	      Process p = Runtime.getRuntime().exec(args);
	      p.waitFor();
	    } catch(Exception e) {System.out.println(e); }

	    //compiler.compile(args);
	  }
	}

	if((errors.size() > 0) || (warnings.size() > 0))
	  System.out.println(errors.size() + " errors and " + warnings.size() +
			     " warnings.");
      }
    } catch(Exception e) { e.printStackTrace(); }
  }


  final static void addError(int line, int column, String err) {
    if(pass != 2)
      errors.addElement(file + ":" + fillup(line, 3) + "," + fillup(column, 2) +
	  	        ": " + err);
  }

  final static void addWarning(int line, int column, String err) {
    warnings.addElement("Warning: " + file + ":" + fillup(line, 3) + "," +
			fillup(column, 3) + ": " + err);
  }

  final static String fillup(int n, int len) {
    String str  = Integer.toString(n);
    int    diff = len - str.length();

    if(diff > 0) {
      char[] chs = new char[diff];
      
      for(int i=0; i < diff; i++)
	chs[i] = ' ';

      return new String(chs) + str;
    }
    else
      return str;
  }

  final static void addWarning(String err) { warnings.addElement(err); }
}