preprocessor.java

类似QQ的功能

/*******************************************************************************
SiJaPP - Simple Java PreProcessor
Copyright (C) 2003  Manuel Linsmayer

This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
*******************************************************************************/


package sijapp;


import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.util.Enumeration;
import java.util.Hashtable;
import java.util.Stack;
import java.util.Vector;


public class Preprocessor {


  // Defines
  private Hashtable defines;
  private Hashtable localDefines = new Hashtable();


  // Input stream
  private BufferedReader reader;


  // Output stream
  private BufferedWriter writer;


  // Line counter
  private int lineNum;


  // Stop flag
  private boolean stop;


  // Skip flag/stack
  private boolean skip;
  private Stack skipStack = new Stack();


  // Done flag/stack
  private boolean done;
  private Stack doneStack = new Stack();


  // Constructor
  public Preprocessor(Hashtable defines) {
    this.defines = defines;
  }


  // Evaluate expression
  public Scanner.Token[] evalExpr(Scanner.Token[] tokens) throws SijappException {

    // Create token vector
    Vector t = new Vector();
    for (int i = 0; i < tokens.length; i++) {
      t.add(tokens[i]);
    }

    main: while(true) {

      // T_EXPR_PRS_LEFT T_BOOL T_EXPR_PRS_RIGHT
      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_EXPR_PRS_LEFT) && (t2.getType() == Scanner.Token.T_BOOL) && (t3.getType() == Scanner.Token.T_EXPR_PRS_RIGHT)) {
          t.remove(i+2);
          t.remove(i+1);
          t.remove(i);
          t.add(i, t2);
          continue main;
        }
      }

      // T_IDENT/T_STRING/T_EXPR_DEF T_EXPR_EQ T_IDENT/T_STRING/T_EXPR_DEF
      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_IDENT) && (t2.getType() == Scanner.Token.T_EXPR_EQ) && (t3.getType() == Scanner.Token.T_IDENT)) {
          t.remove(i+2);
          t.remove(i+1);
          t.remove(i);
          String left = (String) this.localDefines.get(t1.getValue());
          String right = (String) this.localDefines.get(t3.getValue());
          if (((left == null) && (right != null)) || ((left != null) && (right == null))) {
            t.add(i, new Scanner.Token(Scanner.Token.T_BOOL, new Boolean(false)));
            continue main;
          }
          else if ((left == null) && (right == null)) {
            t.add(i, new Scanner.Token(Scanner.Token.T_BOOL, new Boolean(true)));
            continue main;
          }
          else {
            t.add(i, new Scanner.Token(Scanner.Token.T_BOOL, new Boolean(left.equals(right))));
            continue main;
          }
        }
        else if ((t1.getType() == Scanner.Token.T_IDENT) && (t2.getType() == Scanner.Token.T_EXPR_EQ) && (t3.getType() == Scanner.Token.T_STRING)) {
          t.remove(i+2);
          t.remove(i+1);
          t.remove(i);
          String left = (String) this.localDefines.get(t1.getValue());
          String right = (String) t3.getValue();
          if (left == null) {
            t.add(i, new Scanner.Token(Scanner.Token.T_BOOL, new Boolean(false)));
            continue main;
          }
          else {
            t.add(i, new Scanner.Token(Scanner.Token.T_BOOL, new Boolean(left.equals(right))));
            continue main;
          }
        }
        else if ((t1.getType() == Scanner.Token.T_IDENT) && (t2.getType() == Scanner.Token.T_EXPR_EQ) && (t3.getType() == Scanner.Token.T_EXPR_DEF)) {
          t.remove(i+2);
          t.remove(i+1);
          t.remove(i);
          t.add(i, new Scanner.Token(Scanner.Token.T_BOOL, new Boolean(this.localDefines.containsKey(t1.getValue()))));
          continue main;
        }
        else if ((t1.getType() == Scanner.Token.T_STRING) && (t2.getType() == Scanner.Token.T_EXPR_EQ) && (t3.getType() == Scanner.Token.T_IDENT)) {
          t.remove(i+2);
          t.remove(i+1);
          t.remove(i);
          String right = (String) this.localDefines.get(t1.getValue());
          String left = (String) t1.getValue();
          if (left == null) {
            t.add(i, new Scanner.Token(Scanner.Token.T_BOOL, new Boolean(false)));
            continue main;
          }
          else {
            t.add(i, new Scanner.Token(Scanner.Token.T_BOOL, new Boolean(left.equals(right))));
            continue main;
          }
        }
        else if ((t1.getType() == Scanner.Token.T_STRING) && (t2.getType() == Scanner.Token.T_EXPR_EQ) && (t3.getType() == Scanner.Token.T_STRING)) {
          t.remove(i+2);
          t.remove(i+1);
          t.remove(i);
          String left = (String) t1.getValue();
          String right = (String) t3.getValue();
          t.add(i, new Scanner.Token(Scanner.Token.T_BOOL, new Boolean(left.equals(right))));
          continue main;
        }
        else if ((t1.getType() == Scanner.Token.T_STRING) && (t2.getType() == Scanner.Token.T_EXPR_EQ) && (t3.getType() == Scanner.Token.T_EXPR_DEF)) {
          t.remove(i+2);
          t.remove(i+1);
          t.remove(i);
          t.add(i, new Scanner.Token(Scanner.Token.T_BOOL, new Boolean(true)));
          continue main;
        }
        else if ((t1.getType() == Scanner.Token.T_EXPR_DEF) && (t2.getType() == Scanner.Token.T_EXPR_EQ) && (t3.getType() == Scanner.Token.T_IDENT)) {
          t.remove(i+2);
          t.remove(i+1);
          t.remove(i);
          t.add(i, new Scanner.Token(Scanner.Token.T_BOOL, new Boolean(this.localDefines.containsKey(t3.getValue()))));
          continue main;
        }
        else if ((t1.getType() == Scanner.Token.T_EXPR_DEF) && (t2.getType() == Scanner.Token.T_EXPR_EQ) && (t3.getType() == Scanner.Token.T_STRING)) {
          t.remove(i+2);
          t.remove(i+1);
          t.remove(i);
          t.add(i, new Scanner.Token(Scanner.Token.T_BOOL, new Boolean(true)));
          continue main;
        }
        else if ((t1.getType() == Scanner.Token.T_EXPR_DEF) && (t2.getType() == Scanner.Token.T_EXPR_EQ) && (t3.getType() == Scanner.Token.T_EXPR_DEF)) {
          t.remove(i+2);
          t.remove(i+1);
          t.remove(i);
          t.add(i, new Scanner.Token(Scanner.Token.T_BOOL, new Boolean(true)));
          continue main;
        }
      }

      // T_IDENT/T_STRING/T_EXPR_DEF T_EXPR_NEQ T_IDENT/T_STRING/T_EXPR_DEF
      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_IDENT) && (t2.getType() == Scanner.Token.T_EXPR_NEQ) && (t3.getType() == Scanner.Token.T_IDENT)) {
          t.remove(i+2);
          t.remove(i+1);
          t.remove(i);
          String left = (String) this.localDefines.get(t1.getValue());
          String right = (String) this.localDefines.get(t3.getValue());
          if (((left == null) && (right != null)) || ((left != null) && (right == null))) {
            t.add(i, new Scanner.Token(Scanner.Token.T_BOOL, new Boolean(true)));
            continue main;
          }
          else if ((left == null) && (right == null)) {
            t.add(i, new Scanner.Token(Scanner.Token.T_BOOL, new Boolean(false)));
            continue main;
          }
          else {
            t.add(i, new Scanner.Token(Scanner.Token.T_BOOL, new Boolean(!left.equals(right))));
            continue main;
          }
        }
        else if ((t1.getType() == Scanner.Token.T_IDENT) && (t2.getType() == Scanner.Token.T_EXPR_NEQ) && (t3.getType() == Scanner.Token.T_STRING)) {
          t.remove(i+2);
          t.remove(i+1);
          t.remove(i);
          String left = (String) this.localDefines.get(t1.getValue());
          String right = (String) t3.getValue();
          if (left == null) {
            t.add(i, new Scanner.Token(Scanner.Token.T_BOOL, new Boolean(true)));
            continue main;
          }
          else {
            t.add(i, new Scanner.Token(Scanner.Token.T_BOOL, new Boolean(!left.equals(right))));
            continue main;
          }
        }
        else if ((t1.getType() == Scanner.Token.T_IDENT) && (t2.getType() == Scanner.Token.T_EXPR_NEQ) && (t3.getType() == Scanner.Token.T_EXPR_DEF)) {
          t.remove(i+2);
          t.remove(i+1);
          t.remove(i);
          t.add(i, new Scanner.Token(Scanner.Token.T_BOOL, new Boolean(!this.localDefines.containsKey(t1.getValue()))));
          continue main;
        }
        else if ((t1.getType() == Scanner.Token.T_STRING) && (t2.getType() == Scanner.Token.T_EXPR_NEQ) && (t3.getType() == Scanner.Token.T_IDENT)) {
          t.remove(i+2);
          t.remove(i+1);
          t.remove(i);
          String right = (String) this.localDefines.get(t1.getValue());
          String left = (String) t1.getValue();
          if (left == null) {
            t.add(i, new Scanner.Token(Scanner.Token.T_BOOL, new Boolean(true)));
            continue main;
          }
          else {
            t.add(i, new Scanner.Token(Scanner.Token.T_BOOL, new Boolean(!left.equals(right))));
            continue main;
          }
        }
        else if ((t1.getType() == Scanner.Token.T_STRING) && (t2.getType() == Scanner.Token.T_EXPR_NEQ) && (t3.getType() == Scanner.Token.T_STRING)) {
          t.remove(i+2);
          t.remove(i+1);
          t.remove(i);
          String left = (String) t1.getValue();
          String right = (String) t3.getValue();
          t.add(i, new Scanner.Token(Scanner.Token.T_BOOL, new Boolean(!left.equals(right))));
          continue main;
        }
        else if ((t1.getType() == Scanner.Token.T_STRING) && (t2.getType() == Scanner.Token.T_EXPR_NEQ) && (t3.getType() == Scanner.Token.T_EXPR_DEF)) {
          t.remove(i+2);
          t.remove(i+1);
          t.remove(i);
          t.add(i, new Scanner.Token(Scanner.Token.T_BOOL, new Boolean(false)));
          continue main;
        }
        else if ((t1.getType() == Scanner.Token.T_EXPR_DEF) && (t2.getType() == Scanner.Token.T_EXPR_NEQ) && (t3.getType() == Scanner.Token.T_IDENT)) {
          t.remove(i+2);
          t.remove(i+1);
          t.remove(i);
          t.add(i, new Scanner.Token(Scanner.Token.T_BOOL, new Boolean(!this.localDefines.containsKey(t3.getValue()))));
          continue main;
        }
        else if ((t1.getType() == Scanner.Token.T_EXPR_DEF) && (t2.getType() == Scanner.Token.T_EXPR_NEQ) && (t3.getType() == Scanner.Token.T_STRING)) {
          t.remove(i+2);
          t.remove(i+1);
          t.remove(i);
          t.add(i, new Scanner.Token(Scanner.Token.T_BOOL, new Boolean(false)));
          continue main;
        }
        else if ((t1.getType() == Scanner.Token.T_EXPR_DEF) && (t2.getType() == Scanner.Token.T_EXPR_NEQ) && (t3.getType() == Scanner.Token.T_EXPR_DEF)) {
          t.remove(i+2);
          t.remove(i+1);