计算器算法（支持加减乘除括号）

import java.util.ArrayList;
import java.util.List;
import java.util.Stack;

public class Calculator {

	/**
	 * @param args
	 */
	public static void main(String[] args) throws Exception {
		List<String>houzhuishi = houzhui("(0.006+(3-1))/(2+1)+3*2");
		//List<String>houzhuishi = houzhui("(600+(30000-1))/(2+1)+3*2");
		//Double a = Calucate.recursiveCalStr("6+(3-1)/(2+1)+3*2");
		System.out.println(calcResult(houzhuishi));
	}

	public static double calcResult(List<String> houzhishi) throws Exception{
		Stack<Double> charStack = new Stack<Double>();
		for (String str : houzhishi) {
			if (getHuHao().contains(str)) {
				Double data1 = charStack.pop();
				Double data2 = charStack.pop();
				charStack.push(cal(str.charAt(0),data2,data1));
			} else {
				charStack.push(Double.valueOf(str));
			}
		}
		return charStack.peek();
	}
	public static List<String> getHuHao() {
		List<String> huhao = new ArrayList<String>(0);
		huhao.add("+");
		huhao.add("-");
		huhao.add("*");
		huhao.add("/");
		huhao.add("(");
		huhao.add(")");
		huhao.add("#");
		return huhao;
	}
	public static Double cal(char c,double a,double b) throws Exception{
		switch(c){
		case '+':
			return a+b;
		case '-':
			return a-b;
		case '*':
			return a*b;
		case '/':
			return a/b;
		default:
			throw new Exception("XX");	
		}
	}
	
	public static List<String> houzhui(String val) {
		List<String> result = new ArrayList<String>();
		Stack<String> charStack = new Stack<String>();
		charStack.push("#");
		val = val + "#";
		int[][] dir = {
				{1,1,0,0,0,1,1},
				{1,1,0,0,0,1,1},
				{1,1,1,1,0,1,1},
				{1,1,1,1,0,1,1},
				{0,0,0,0,0,2,-1},
				{1,1,1,1,-1,1,1},
				{0,0,0,0,0,-1,2},
				};
		List<String> test = new ArrayList<String>();
		StringBuilder temp = new StringBuilder();
		for(int i = 0 ,length = val.length(); i < length ; i++) {
			String chr = String.valueOf(val.charAt(i));
			if (getHuHao().contains(chr) ) {
				if (temp.length() > 0) {
					test.add(temp.toString());
				}
				test.add(chr);
				temp.delete(0, temp.length());
			} else {
				temp.append(chr);
			}
		}
		
		for (int i = 0 ,size = test.size(); i < size ; i++) {
			String str = test.get(i);
			try {
				Double.valueOf(str);
				result.add(str);
			} catch (NumberFormatException e) {
				int x = getHuHao().indexOf(str);
				int y = getHuHao().indexOf(charStack.peek());
				if (dir[y][x] == 0) {
					charStack.push(str);
				} else if (dir[y][x] == 1) {
					result.add(charStack.pop());
					i --;
				} else if (dir[y][x] == 2 && (x == 5 && y == 4 )) {
					charStack.pop();
				} else if (dir[y][x] == 2 && (x == 6 && y == 6 )) {
					break;
				} else {
					break;
				}
			}
		}
		return result;
	}
}

 附件中有算法解释。