parseengine.java

java 编译器java复杂编译器,可以编译java文件的类库

      // there's no need to check it below for "e_nrw" and "ntexp".  In
      // fact, we rely here on the fact that the "name" fields of both these
      // variables are the same.
      NonTerminal e_nrw = (NonTerminal)e;
      NormalProduction ntprod = (NormalProduction)(production_table.get(e_nrw.name));
      if (ntprod instanceof JavaCodeProduction) {
        ; // nothing to do here
      } else {
        generate3R(ntprod.expansion, inf);
      }
    } else if (e instanceof Choice) {
      Choice e_nrw = (Choice)e;
      for (int i = 0; i < e_nrw.choices.size(); i++) {
        generate3R((Expansion)(e_nrw.choices.elementAt(i)), inf);
      }
    } else if (e instanceof Sequence) {
      Sequence e_nrw = (Sequence)e;
      // We skip the first element in the following iteration since it is the
      // Lookahead object.
      int cnt = inf.count;
      for (int i = 1; i < e_nrw.units.size(); i++) {
        Expansion eseq = (Expansion)(e_nrw.units.elementAt(i));
        setupPhase3Builds(new Phase3Data(eseq, cnt));
        cnt -= minimumSize(eseq);
        if (cnt <= 0) break;
      }
    } else if (e instanceof TryBlock) {
      TryBlock e_nrw = (TryBlock)e;
      setupPhase3Builds(new Phase3Data(e_nrw.exp, inf.count));
    } else if (e instanceof OneOrMore) {
      OneOrMore e_nrw = (OneOrMore)e;
      generate3R(e_nrw.expansion, inf);
    } else if (e instanceof ZeroOrMore) {
      ZeroOrMore e_nrw = (ZeroOrMore)e;
      generate3R(e_nrw.expansion, inf);
    } else if (e instanceof ZeroOrOne) {
      ZeroOrOne e_nrw = (ZeroOrOne)e;
      generate3R(e_nrw.expansion, inf);
    }
  }

  private static String genjj_3Call(Expansion e)
  {
     if (e.internal_name.startsWith("jj_scan_token"))
        return e.internal_name;
     else
        return "jj_3" + e.internal_name + "()";
  }

  static Hashtable generated = new Hashtable();
  static void buildPhase3Routine(Phase3Data inf, boolean recursive_call) {
    Expansion e = inf.exp;
    Token t = null;
    if (e.internal_name.startsWith("jj_scan_token"))
       return;

    if (!recursive_call) {
      ostr.println("  " + staticOpt() + "final private boolean jj_3" + e.internal_name + "() {");
      xsp_declared = false;
      if (Options.B("DEBUG_LOOKAHEAD") && e.parent instanceof NormalProduction) {
        ostr.print("    ");
        if (Options.B("ERROR_REPORTING")) {
          ostr.print("if (!jj_rescan) ");
        }
        ostr.println("trace_call(\"" + ((NormalProduction)e.parent).lhs + "(LOOKING AHEAD...)\");");
        jj3_expansion = e;
      } else {
        jj3_expansion = null;
      }
    }
    if (e instanceof RegularExpression) {
      RegularExpression e_nrw = (RegularExpression)e;
      if (e_nrw.label.equals("")) {
        Object label = names_of_tokens.get(new Integer(e_nrw.ordinal));
        if (label != null) {
          ostr.println("    if (jj_scan_token(" + (String)label + ")) " + genReturn(true));
        } else {
          ostr.println("    if (jj_scan_token(" + e_nrw.ordinal + ")) " + genReturn(true));
        }
      } else {
        ostr.println("    if (jj_scan_token(" + e_nrw.label + ")) " + genReturn(true));
      }
      //ostr.println("    if (jj_la == 0 && jj_scanpos == jj_lastpos) " + genReturn(false));
    } else if (e instanceof NonTerminal) {
      // All expansions of non-terminals have the "name" fields set.  So
      // there's no need to check it below for "e_nrw" and "ntexp".  In
      // fact, we rely here on the fact that the "name" fields of both these
      // variables are the same.
      NonTerminal e_nrw = (NonTerminal)e;
      NormalProduction ntprod = (NormalProduction)(production_table.get(e_nrw.name));
      if (ntprod instanceof JavaCodeProduction) {
        ostr.println("    if (true) { jj_la = 0; jj_scanpos = jj_lastpos; " + genReturn(false) + "}");
      } else {
        Expansion ntexp = ntprod.expansion;
        //ostr.println("    if (jj_3" + ntexp.internal_name + "()) " + genReturn(true));
        ostr.println("    if (" + genjj_3Call(ntexp)+ ") " + genReturn(true));
        //ostr.println("    if (jj_la == 0 && jj_scanpos == jj_lastpos) " + genReturn(false));
      }
    } else if (e instanceof Choice) {
      if (!xsp_declared) {
        xsp_declared = true;
        ostr.println("    Token xsp;");
      }
      ostr.println("    xsp = jj_scanpos;");
      Sequence nested_seq;
      Choice e_nrw = (Choice)e;
      for (int i = 0; i < e_nrw.choices.size(); i++) {
        nested_seq = (Sequence)(e_nrw.choices.elementAt(i));
        Lookahead la = (Lookahead)(nested_seq.units.elementAt(0));
        if (la.action_tokens.size() != 0) {
          // We have semantic lookahead that must be evaluated.
          ostr.println("    lookingAhead = true;");
          ostr.print("    jj_semLA = ");
          printTokenSetup((Token)(la.action_tokens.elementAt(0)));
          for (java.util.Enumeration enum = la.action_tokens.elements(); enum.hasMoreElements();) {
            t = (Token)enum.nextElement();
            printToken(t, ostr);
          }
          printTrailingComments(t, ostr);
          ostr.println(";");
          ostr.println("    lookingAhead = false;");
        }
        ostr.print("    if (");
        if (la.action_tokens.size() != 0) {
          ostr.print("!jj_semLA || ");
        }
        if (i != e_nrw.choices.size() - 1) {
          //ostr.println("jj_3" + nested_seq.internal_name + "()) {");
          ostr.println(genjj_3Call(nested_seq) + ") {");
          ostr.println("    jj_scanpos = xsp;");
        } else {
          //ostr.println("jj_3" + nested_seq.internal_name + "()) " + genReturn(true));
          ostr.println(genjj_3Call(nested_seq) + ") " + genReturn(true));
          //ostr.println("    if (jj_la == 0 && jj_scanpos == jj_lastpos) " + genReturn(false));
        }
      }
      for (int i = 1; i < e_nrw.choices.size(); i++) {
        //ostr.println("    } else if (jj_la == 0 && jj_scanpos == jj_lastpos) " + genReturn(false));
        ostr.println("    }");
      }
    } else if (e instanceof Sequence) {
      Sequence e_nrw = (Sequence)e;
      // We skip the first element in the following iteration since it is the
      // Lookahead object.
      int cnt = inf.count;
      for (int i = 1; i < e_nrw.units.size(); i++) {
        Expansion eseq = (Expansion)(e_nrw.units.elementAt(i));
        buildPhase3Routine(new Phase3Data(eseq, cnt), true);

//System.out.println("minimumSize: line: " + eseq.line + ", column: " + eseq.column + ": " + minimumSize(eseq));//Test Code

        cnt -= minimumSize(eseq);
        if (cnt <= 0) break;
      }
    } else if (e instanceof TryBlock) {
      TryBlock e_nrw = (TryBlock)e;
      buildPhase3Routine(new Phase3Data(e_nrw.exp, inf.count), true);
    } else if (e instanceof OneOrMore) {
      if (!xsp_declared) {
        xsp_declared = true;
        ostr.println("    Token xsp;");
      }
      OneOrMore e_nrw = (OneOrMore)e;
      Expansion nested_e = e_nrw.expansion;
      //ostr.println("    if (jj_3" + nested_e.internal_name + "()) " + genReturn(true));
      ostr.println("    if (" + genjj_3Call(nested_e) + ") " + genReturn(true));
      //ostr.println("    if (jj_la == 0 && jj_scanpos == jj_lastpos) " + genReturn(false));
      ostr.println("    while (true) {");
      ostr.println("      xsp = jj_scanpos;");
      //ostr.println("      if (jj_3" + nested_e.internal_name + "()) { jj_scanpos = xsp; break; }");
      ostr.println("      if (" + genjj_3Call(nested_e) + ") { jj_scanpos = xsp; break; }");
      //ostr.println("      if (jj_la == 0 && jj_scanpos == jj_lastpos) " + genReturn(false));
      ostr.println("    }");
    } else if (e instanceof ZeroOrMore) {
      if (!xsp_declared) {
        xsp_declared = true;
        ostr.println("    Token xsp;");
      }
      ZeroOrMore e_nrw = (ZeroOrMore)e;
      Expansion nested_e = e_nrw.expansion;
      ostr.println("    while (true) {");
      ostr.println("      xsp = jj_scanpos;");
      //ostr.println("      if (jj_3" + nested_e.internal_name + "()) { jj_scanpos = xsp; break; }");
      ostr.println("      if (" + genjj_3Call(nested_e) + ") { jj_scanpos = xsp; break; }");
      //ostr.println("      if (jj_la == 0 && jj_scanpos == jj_lastpos) " + genReturn(false));
      ostr.println("    }");
    } else if (e instanceof ZeroOrOne) {
      if (!xsp_declared) {
        xsp_declared = true;
        ostr.println("    Token xsp;");
      }
      ZeroOrOne e_nrw = (ZeroOrOne)e;
      Expansion nested_e = e_nrw.expansion;
      ostr.println("    xsp = jj_scanpos;");
      //ostr.println("    if (jj_3" + nested_e.internal_name + "()) jj_scanpos = xsp;");
      ostr.println("    if (" + genjj_3Call(nested_e) + ") jj_scanpos = xsp;");
      //ostr.println("    else if (jj_la == 0 && jj_scanpos == jj_lastpos) " + genReturn(false));
    }
    if (!recursive_call) {
      ostr.println("    " + genReturn(false));
      ostr.println("  }");
      ostr.println("");
    }
  }

  /*
   * Returns the minimum number of tokens that can parse to this expansion.
   */
  static int minimumSize(Expansion e) {
    int retval = 0;  // should never be used.  Will be bad if it is.
    if (e.inMinimumSize) {
      // recursive search for minimum size unnecessary.
      return Integer.MAX_VALUE;
    }
    e.inMinimumSize = true;
    if (e instanceof RegularExpression) {
      retval = 1;
    } else if (e instanceof NonTerminal) {
      NonTerminal e_nrw = (NonTerminal)e;
      NormalProduction ntprod = (NormalProduction)(production_table.get(e_nrw.name));
      if (ntprod instanceof JavaCodeProduction) {
        retval = Integer.MAX_VALUE;
        // Make caller think this is unending (for we do not go beyond JAVACODE during
        // phase3 execution).
      } else {
        Expansion ntexp = ntprod.expansion;
        retval = minimumSize(ntexp);
      }
    } else if (e instanceof Choice) {
      int min = Integer.MAX_VALUE;
      Expansion nested_e;
      Choice e_nrw = (Choice)e;
      for (int i = 0; i < e_nrw.choices.size(); i++) {
        nested_e = (Expansion)(e_nrw.choices.elementAt(i));
        int min1 = minimumSize(nested_e);
        if (min > min1) min = min1;
      }
      retval = min;
    } else if (e instanceof Sequence) {
      int min = 0;
      Sequence e_nrw = (Sequence)e;
      // We skip the first element in the following iteration since it is the
      // Lookahead object.
      for (int i = 1; i < e_nrw.units.size(); i++) {
        Expansion eseq = (Expansion)(e_nrw.units.elementAt(i));
        int mineseq = minimumSize(eseq);
        if (min == Integer.MAX_VALUE || mineseq == Integer.MAX_VALUE) {
          min = Integer.MAX_VALUE; // Adding infinity to something results in infinity.
        } else {
          min += mineseq;
        }
      }
      retval = min;
    } else if (e instanceof TryBlock) {
      TryBlock e_nrw = (TryBlock)e;
      retval = minimumSize(e_nrw.exp);
    } else if (e instanceof OneOrMore) {
      OneOrMore e_nrw = (OneOrMore)e;
      retval = minimumSize(e_nrw.expansion);
    } else if (e instanceof ZeroOrMore) {
      retval = 0;
    } else if (e instanceof ZeroOrOne) {
      retval = 0;
    } else if (e instanceof Lookahead) {
      retval = 0;
    } else if (e instanceof Action) {
      retval = 0;
    }
    e.inMinimumSize = false;
    return retval;
  }

  static void build(java.io.PrintWriter ps) {
    NormalProduction p;
    JavaCodeProduction jp;
    Token t = null;

    ostr = ps;

    for (java.util.Enumeration enum = bnfproductions.elements(); enum.hasMoreElements();) {
      p = (NormalProduction)enum.nextElement();
      if (p instanceof JavaCodeProduction) {
        jp = (JavaCodeProduction)p;
        t = (Token)(jp.return_type_tokens.elementAt(0));
        printTokenSetup(t); ccol = 1;
        printLeadingComments(t, ostr);
        ostr.print("  " + staticOpt());
        cline = t.beginLine; ccol = t.beginColumn;
        printTokenOnly(t, ostr);
        for (int i = 1; i < jp.return_type_tokens.size(); i++) {
          t = (Token)(jp.return_type_tokens.elementAt(i));
          printToken(t, ostr);
        }
        printTrailingComments(t, ostr);
        ostr.print(" " + jp.lhs + "(");
        if (jp.parameter_list_tokens.size() != 0) {
          printTokenSetup((Token)(jp.parameter_list_tokens.elementAt(0)));
          for (java.util.Enumeration enum1 = jp.parameter_list_tokens.elements(); enum1.hasMoreElements();) {
            t = (Token)enum1.nextElement();
            printToken(t, ostr);
          }
          printTrailingComments(t, ostr);
        }
        ostr.print(") throws ParseException");
        for (java.util.Enumeration enum1 = jp.throws_list.elements(); enum1.hasMoreElements();) {
          ostr.print(", ");
          java.util.Vector name = (java.util.Vector)enum1.nextElement();
          for (java.util.Enumeration enum2 = name.elements(); enum2.hasMoreElements();) {
            t = (Token)enum2.nextElement();
            ostr.print(t.image);
          }
        }
        ostr.print(" {");
        if (Options.B("DEBUG_PARSER")) {
          ostr.println("");
          ostr.println("    trace_call(\"" + jp.lhs + "\");");
          ostr.print("    try {");
        }
        if (jp.code_tokens.size() != 0) {
          printTokenSetup((Token)(jp.code_tokens.elementAt(0))); cline--;
          for (java.util.Enumeration enum1 = jp.code_tokens.elements(); enum1.hasMoreElements();) {
            t = (Token)enum1.nextElement();
            printToken(t, ostr);
          }
          printTrailingComments(t, ostr);
        }
        ostr.println("");
        if (Options.B("DEBUG_PARSER")) {
          ostr.println("    } finally {");
          ostr.println("      trace_return(\"" + jp.lhs + "\");");
          ostr.println("    }");
        }
        ostr.println("  }");
        ostr.println("");
      } else {
        buildPhase1Routine((BNFProduction)p);
      }
    }

    for (int phase2index = 0; phase2index < phase2list.size(); phase2index++) {
      buildPhase2Routine((Lookahead)(phase2list.elementAt(phase2index)));
    }

    int phase3index = 0;

    while (phase3index < phase3list.size()) {
      for (; phase3index < phase3list.size(); phase3index++) {
        setupPhase3Builds((Phase3Data)(phase3list.elementAt(phase3index)));
      }
    }

    for (java.util.Enumeration enum = phase3table.elements(); enum.hasMoreElements();) {
      buildPhase3Routine((Phase3Data)(enum.nextElement()), false);
    }

  }

   public static void reInit()
   {
      ostr = null;
      gensymindex = 0;
      indentamt = (int)0;
      jj2LA = false;
      phase2list = new java.util.Vector();
      phase3list = new java.util.Vector();
      phase3table = new java.util.Hashtable();
      firstSet = null;
      xsp_declared = false;
      jj3_expansion = null;
   }

}

/*
 * This class stored information to pass from phase 2 to phase 3.
 */
class Phase3Data {

  /*
   * This is the expansion to generate the jj3 method for.
   */
  Expansion exp;

  /*
   * This is the number of tokens that can still be consumed.  This
   * number is used to limit the number of jj3 methods generated.
   */
  int count;

  Phase3Data(Expansion e, int c) {
    exp = e;
    count = c;
  }

}