表示式計算原始碼JAVA實現 (轉)

表示式計算原始碼JAVA實現 (轉)[@more@]

支援運算子：+-*/%>

支援：sqrt,square, ceil,sin,cos,asin,acon.tan.atan,log,exp具體含義見calFunction程式碼

計算原始碼：

import .util.Stack;
import java.util.regex.*;

public class BaseExpression {
  public static String OPTS = "+-*/%>  public calculate(String expression)  throws ExpressionException{
  try
  {
  Stack Opts = new Stack();
  Stack Values = new Stack();
  String e= expression + "#";
  int nCount = exp.length(), nIn, nOut, nTemp;
  Opts.push("#");
  String temp = "", optOut = "", optIn = "", value1 = "", value2 = "",
  optTemp = "", opt = "", temp1 = "";
  int nFun = 0;
  boolean iun = false;
  for (int i = 0; i < nCount; ) {
  nTemp = 0;
  opt = exp.substring(i, i + 1);
  isFun = false;
  temp1 = "";
  while (i < nCount) {
  if (!temp1.equals("")) {
  if (opt.equals("(")) {
  nFun++;
  isFun = true;
  }
  else if (opt.equals(")")) {
  nFun--;
  }
  }
  if ( (nFun > 0) || ( (!isFun) && this.isValue(opt))) {
  temp1 += opt;
  nTemp++;
  opt = exp.substring(i + nTemp, i + nTemp + 1);
  }
  else {
  if (isFun) {
  temp1 += opt;
  nTemp++;
  }
  break;
  }
  }
  if (temp1.equals("")) {
  temp = opt;
  }
  else {
  temp = temp1;
  }
  if (nTemp > 0) {
  i = i + nTemp - 1;
  }
  temp = temp.trim();

  if (this.isValue(temp)) {
  temp = this.getValue(temp);
  Values.push(temp);
  i++;
  }
  else {
  optIn = Opts.pop().toString();
  nIn = this.getOptPriorityIn(optIn);
  nOut = this.getOptPriorityOut(temp);
  if (nIn == nOut) {
  i++;
  }
  else if (nIn > nOut) {
  String ret = "";
  value1 = Values.pop().toString();
  value2 = Values.pop().toString();
  ret = String.valueOf(this.calValue(value2, optIn, value1));
  Values.push(ret);
  }
  else if (nIn < nOut) {
  Opts.push(optIn);
  Opts.push(temp);
  i++;
  }
  }
  }
  return Values.pop();
  }
  catch(ExpressionException eE)
  {
  throw eE;
  }
  catch(Exception e)
  {
  throw new ExpressionException("表示式" + expression + "格式!");
  }
  }

  protected int getOptPriorityOut(String opt) throws ExpressionException{
  if (opt.equals("+")) {
  return 1;
  }
  else if (opt.equals("-")) {
  return 2;
  }
  else if (opt.equals("*")) {
  return 5;
  }
  else if (opt.equals("/")) {
  return 6;
  }
  else if (opt.equals("%")) {
  return 7;
  }
  else if (opt.equals(">")) {
  return 11;
  }
  else if (opt.equals("  return 12;
  }
  else if (opt.equals("]")) {
  return 13;
  }
  else if (opt.equals("[")) {
  return 14;
  }
  else if (opt.equals("!")) {
  return 15;
  }
  else if (opt.equals("|")) {
  return 16;
  }
  else if (opt.equals("&") )
  {
  return 23;
  }
  else if (opt.equals("=") )
  {
  return 25;
  }
  else if ( opt.equals("#"))
  {
  return 0;
  }
  else if (opt.equals("(")) {
  return 1000;
  }
  else if (opt.equals(")")) {
  return -1000;
  }
  throw new ExpressionException("運算子" + opt + "非法!");
  }

  protected int getOptPriorityIn(String opt)  throws ExpressionException{
  if (opt.equals("+")) {
  return 3;
  }
  else if (opt.equals("-")) {
  return 4;
  }
  else if (opt.equals("*")) {
  return 8;
  }
  else if (opt.equals("/")) {
  return 9;
  }
  else if (opt.equals("%")) {
  return 10;
  }
  else if (opt.equals(">")) {
  return 17;
  }
  else if (opt.equals("  return 18;
  }
  else if (opt.equals("]")) {
  return 19;
  }
  else if (opt.equals("[")) {
  return 20;
  }
  else if (opt.equals("!")) {
  return 21;
  }
  else if (opt.equals("|")) {
  return 22;
  }
  else if( opt.equals("&") )
  {
  return 24;
  }
  else if( opt.equals("=") )
  {
  return 26;
  }
  else if (opt.equals("(")) {
  return -1000;
  }
  else if (opt.equals(")")) {
  return 1000;
  }
  else if (opt.equals("#")) {
  return 0;
  }
  throw new ExpressionException("運算子" + opt + "非法！");
  }

  protected String getOPTS()
  {
  return OPTS;
  }
  protected boolean isValue(String cValue) {
  String notValue = this.getOPTS() + "()";
  return notValue.indexOf(cValue) == -1;
  }

  protected boolean isOpt(String value) {
  return this.getOPTS().indexOf(value) >= 0;
  }

  protected double calValue(String value1, String opt, String value2)  throws ExpressionException{
  try
  {
  double Value1 = Double.valueOf(value1).doubleValue();
  double dbValue2 = Double.valueOf(value2).doubleValue();
  long lg = 0;
  if (opt.equals("+")) {
  return dbValue1 + dbValue2;
  }
  else if (opt.equals("-")) {
  return dbValue1 - dbValue2;
  }
  else if (opt.equals("*")) {
  return dbValue1 * dbValue2;
  }
  else if (opt.equals("/")) {
  return dbValue1 / dbValue2;
  }
  else if (opt.equals("%")) {
  lg = (long) (dbValue1 / dbValue2);
  return dbValue1 - lg * dbValue2;
  }
  else if (opt.equals(">")) {
  if (dbValue1 > dbValue2)
  return 1;
  else
  return 0;
  }
  else if (opt.equals("  if (dbValue1 < dbValue2)
  return 1;
  else
  return 0;
  }
  else if (opt.equals("]")) {
  if (dbValue1 >= dbValue2)
  return 1;
  else
  return 0;
  }
  else if (opt.equals("[")) {
  if (dbValue1 <= dbValue2)
  return 1;
  else
  return 0;
  }
  else if (opt.equals("!")) {
  if (dbValue1 != dbValue2)
  return 1;
  else
  return 0;
  }
  else if (opt.equals("|")) {
  if (dbValue1 > 0 || dbValue2 > 0)
  return 1;
  else
  return 0;
  }
  else if (opt.equals("&")) {
  if (dbValue1 > 0 && dbValue2 > 0)
  return 1;
  else
  return 0;
  }
  else if (opt.equals("=")) {
  if (dbValue1 == dbValue2)
  return 1;
  else
  return 0;
  }
  }catch(Exception e)
  {
  throw new ExpressionException("值" + value1 + "或" + value2 + "在進行" +  opt + "運算時非法！");
  }
  throw new ExpressionException("運算子" + opt + "非法！");
  }

  protected String getValue(String oldValue)  throws ExpressionException{
  String reg = "^([a-zA-Z0-9_]+)(([a-zA-Z0-9_.()]+))$";
  if (this.isFunctionCal(oldValue)) {
  Pattern p = Pattern.compile(reg);
  Matcher m = p.matcher(oldValue);
  m.find();
  return calFunction(m.group(1), m.group(2));
  }
  return oldValue;
  }

  protected boolean isFunctionCal(String value) {
  String reg = "^([a-zA-Z0-9_]+)(([a-zA-Z0-9_.()]+))$";
  return value.matches(reg);
  }

  protected String calFunction(String function, String value)  throws ExpressionException{
  String lowerFun = function.toLowerCase();
  double db = 0;
  try
  {
  db = Double.valueOf(this.getValue(value)).doubleValue();
  if (lowerFun.equals("log")) {
  return String.valueOf(Math.log(db));
  }
  else if (lowerFun.equals("square")) {
  return String.valueOf(Math.pow(db, 2));
  }
  else if (lowerFun.equals("sqrt")) {
  return String.valueOf(Math.sqrt(db));
  }
  else if (lowerFun.equals("sin")) {
  return String.valueOf(Math.sin(db));
  }
  else if (lowerFun.equals("asin")) {
  return String.valueOf(Math.asin(db));
  }
  else if (lowerFun.equals("cos")) {
  return String.valueOf(Math.cos(db));
  }
  else if (lowerFun.equals("tan")) {
  return String.valueOf(Math.tan(db));
  }
  else if (lowerFun.equals("atan")) {
  return String.valueOf(Math.atan(db));
  }
  else if (lowerFun.equals("ceil")) {
  return String.valueOf(Math.ceil(db));
  }
  else if (lowerFun.equals("exp")) {
  return String.valueOf(Math.exp(db));
  }
  }catch(Exception e)
  {
  throw new ExpressionException("函式" + function + "值" + value + "非法!");
  }

  throw new ExpressionException("函式" + function + "不支援！");
  }
   public static void main(String[] args)
   {
   BaseExpression be = new BaseExpression();
   String exp = "sin(ceil(sqrt(100)))*29+20+30*3+0|0|1+1&1*5+2=2";
   try
   {
   System.out.println(be.calculate(exp));
   }
   catch(ExpressionException eE)
   {
   System.out.println(eE.getMessage());
   }
 }
}

表示式異常類程式碼：

public class ExpressionException extends Exception{
  public ExpressionException(String msg)
  {
  super(msg);
  }
}