t.remove(i);          t.add(i, new Scanner.Token(Scanner.Token.T_BOOL, new Boolean(false)));          continue main;        }      }      // T_EXPR_NOT T_BOOL      for (int i = 0; i < t.size()-1; i++) {        Scanner.Token t1 = (Scanner.Token) t.get(i);        Scanner.Token t2 = (Scanner.Token) t.get(i+1);        if ((t1.getType() == Scanner.Token.T_EXPR_NOT) && (t2.getType() == Scanner.Token.T_BOOL)) {          t.remove(i+1);          t.remove(i);          t.add(i, new Scanner.Token(Scanner.Token.T_BOOL, new Boolean(!((Boolean) t2.getValue()).booleanValue())));          continue main;        }      }      // T_BOOL T_EXPR_AND T_BOOL      for (int i = 0; i < t.size()-2; i++) {        Scanner.Token t1 = (Scanner.Token) t.get(i);        Scanner.Token t2 = (Scanner.Token) t.get(i+1);        Scanner.Token t3 = (Scanner.Token) t.get(i+2);        if ((t1.getType() == Scanner.Token.T_BOOL) && (t2.getType() == Scanner.Token.T_EXPR_AND) && (t3.getType() == Scanner.Token.T_BOOL)) {          t.remove(i+2);          t.remove(i+1);          t.remove(i);          t.add(i, new Scanner.Token(Scanner.Token.T_BOOL, new Boolean(((Boolean) t1.getValue()).booleanValue() && ((Boolean) t3.getValue()).booleanValue())));          continue main;        }      }      // T_BOOL T_EXPR_OR T_BOOL      for (int i = 0; i < t.size()-2; i++) {        Scanner.Token t1 = (Scanner.Token) t.get(i);        Scanner.Token t2 = (Scanner.Token) t.get(i+1);        Scanner.Token t3 = (Scanner.Token) t.get(i+2);        if ((t1.getType() == Scanner.Token.T_BOOL) && (t2.getType() == Scanner.Token.T_EXPR_OR) && (t3.getType() == Scanner.Token.T_BOOL)) {          t.remove(i+2);          t.remove(i+1);          t.remove(i);          t.add(i, new Scanner.Token(Scanner.Token.T_BOOL, new Boolean(((Boolean) t1.getValue()).booleanValue() || ((Boolean) t3.getValue()).booleanValue())));          continue main;        }      }      break;    }    // Return resulting tokens as array    Scanner.Token[] ret = new Scanner.Token[t.size()];    t.copyInto(ret);    return (ret);  }  // Evaluate condition (if/unless/elseif/else/end) statement  public void evalCond(Scanner.Token[] tokens) throws SijappException {    // Copy non-evaluted tokens to new array    Scanner.Token[] remainingTokens = new Scanner.Token[tokens.length - 2];    System.arraycopy(tokens, 2, remainingTokens, 0, tokens.length - 2);    // Command condition.if    if ((tokens.length >= 2) && (tokens[0].getType() == Scanner.Token.T_SEP) && (tokens[1].getType() == Scanner.Token.T_CMD2_IF)) {      // Evaluate expression and check result type      Scanner.Token[] resultingTokens = this.evalExpr(remainingTokens);      if ((resultingTokens.length != 1) || (resultingTokens[0].getType() != Scanner.Token.T_BOOL)) {        throw (new SijappException("Syntax error"));      }      boolean result = ((Boolean) resultingTokens[0].getValue()).booleanValue();      // Save state variables      this.skipStack.push(new Boolean(this.skip));      this.doneStack.push(new Boolean(this.done));      // Set state variables      this.skip |= !result;      this.done = result;    }    // Command condition.elseif    else if ((tokens.length >= 2) && (tokens[0].getType() == Scanner.Token.T_SEP) && (tokens[1].getType() == Scanner.Token.T_CMD2_ELSEIF)) {      // Evaluate expression and check result type      Scanner.Token[] resultingTokens = this.evalExpr(remainingTokens);      if ((resultingTokens.length != 1) || (resultingTokens[0].getType() != Scanner.Token.T_BOOL)) {        throw (new SijappException("Syntax error"));      }      boolean result = ((Boolean) resultingTokens[0].getValue()).booleanValue();      // Set state variables      this.skip = ((Boolean) this.skipStack.peek()).booleanValue() || this.done || !result;      this.done |= result;    }    // Command condition.else    else if ((tokens.length == 2) && (tokens[0].getType() == Scanner.Token.T_SEP) && (tokens[1].getType() == Scanner.Token.T_CMD2_ELSE)) {      // Set state variables      this.skip = ((Boolean) this.skipStack.peek()).booleanValue() || this.done;      this.done = true;    }    // Command condition.end    else if ((tokens.length == 2) && (tokens[0].getType() == Scanner.Token.T_SEP) && (tokens[1].getType() == Scanner.Token.T_CMD2_END)) {      // Reset state variables      this.skip = ((Boolean) this.skipStack.pop()).booleanValue();      this.done = ((Boolean) this.doneStack.pop()).booleanValue();    }    // Unknown command/Syntax error    else {      throw (new SijappException("Syntax error"));    }  }  // Evaluate echo statement  public void evalEcho(Scanner.Token[] tokens) throws SijappException {    if ((tokens.length != 1) || (tokens[0].getType() != Scanner.Token.T_STRING)) {      throw (new SijappException("Syntax error"));    }    else if (!this.skip) {      String s = (String) tokens[0].getValue();      try {        writer.write(s, 0, s.length());        writer.newLine();      }      catch (IOException e) {        throw (new SijappException("An I/O error occured"));      }    }  }  // Evaluate enviroment statement  public void evalEnv(Scanner.Token[] tokens) throws SijappException {    if ((tokens.length == 3) && (tokens[0].getType() == Scanner.Token.T_SEP) && (tokens[1].getType() == Scanner.Token.T_CMD2_DEF) && (tokens[2].getType() == Scanner.Token.T_IDENT)) {      if (!this.skip) {        this.localDefines.put(tokens[2].getValue(), "defined");      }    }    else if ((tokens.length == 4) && (tokens[0].getType() == Scanner.Token.T_SEP) && (tokens[1].getType() == Scanner.Token.T_CMD2_DEF) && (tokens[2].getType() == Scanner.Token.T_IDENT) && (tokens[3].getType() == Scanner.Token.T_STRING)) {      if (!this.skip) {        this.localDefines.put(tokens[2].getValue(), tokens[3].getValue());      }    }    else if ((tokens.length == 3) && (tokens[0].getType() == Scanner.Token.T_SEP) && (tokens[1].getType() == Scanner.Token.T_CMD2_UNDEF) && (tokens[2].getType() == Scanner.Token.T_IDENT)) {      if (!this.skip) {        this.localDefines.remove(tokens[2].getValue());      }    }    else {      throw (new SijappException("Syntax error"));    }  }  // Evaluate exit statement  public void evalExit(Scanner.Token[] tokens) throws SijappException {    if (tokens.length != 0) {      throw (new SijappException("Syntax error"));    }    else if (!this.skip) {      this.stop = true;    }  }  // Evaluate SiJaPP statement  public void eval(Scanner.Token[] tokens) throws SijappException {    // Valid statement consists of at least 3 tokens    if (tokens.length < 3) {      throw (new SijappException("Syntax error"));    }    // Look for MAGIC_BEGIN and MAGIC_END    if ((tokens[0].getType() != Scanner.Token.T_MAGIC_BEGIN) || (tokens[tokens.length-1].getType() != Scanner.Token.T_MAGIC_END)) {      throw (new SijappException("Syntax error"));    }    // Copy non-evaluted tokens to new array    Scanner.Token[] remainingTokens = new Scanner.Token[tokens.length - 3];    System.arraycopy(tokens, 2, remainingTokens, 0, tokens.length - 3);    // Delegate evaluation    switch (tokens[1].getType()) {      case Scanner.Token.T_CMD1_COND:        this.evalCond(remainingTokens);        break;      case Scanner.Token.T_CMD1_ECHO:        this.evalEcho(remainingTokens);        break;      case Scanner.Token.T_CMD1_ENV:        this.evalEnv(remainingTokens);        break;      case Scanner.Token.T_CMD1_EXIT:        this.evalExit(remainingTokens);        break;      default:        throw (new SijappException("Syntax error"));    }  }  // Preprocess  public void run(BufferedReader reader, BufferedWriter writer) throws SijappException {    // Restore global defines    this.localDefines.clear();    for (Enumeration keys = this.defines.keys(); keys.hasMoreElements(); ) {      String key = new String((String) keys.nextElement());      String value = new String((String) this.defines.get(key));      this.localDefines.put(key, value);    }    // Save input/output stream    this.reader = reader;    this.writer = writer;    // Reset line counter    this.lineNum = 1;    // Reset stop flag    this.stop = false;    // Reset skip flag    this.skip = false;    // Read until EOF    try {      String line;      while ((line = this.reader.readLine()) != null) {        // Scan read line for s SiJaPP statement        Scanner.Token[] tokens = Scanner.scan(line);        // Get rid of special sijapp comments //# if inside an sijapp statement         if (tokens.length == 0 && line.trim().startsWith("//#") && this.doneStack.size() > 0)        	line = line.trim().substring(3);        // No statement has been found        if (tokens.length == 0) {          if (!skip) {            this.writer.write(line, 0, line.length());            this.writer.newLine();          }          else          {              this.writer.write("//# "+line, 0, line.length()+4);              this.writer.newLine();          }        }        // A statement has been found        else {          this.eval(tokens);          this.writer.write(line, 0, line.length());          this.writer.newLine();          if (this.stop) {            return;          }        }        // Advance line counter        this.lineNum++;      }    }    catch (SijappException e) {      throw (new SijappException(this.lineNum + ": " + e.getMessage()));    }    catch (IOException e) {      throw (new SijappException("An I/O error occured"));    }  }}