好东西分享之计算公式解析与四则运算.doc

JAVA公式解析与四则运算第1章 公式解析与四则运算源码package com.citicpru.clm.ruleengine.util;/* * Title: 公式解析类 * Description: 实现对包含“()、max、min”的表达式进行简单的四则运算。 * Copyright: Copyright (c) 2004 * Company: * author leasion * version 1.0 */import java.lang.reflect.Method;import java.util.ArrayList;import java.util.HashMap;import java.util.List;import java.util.Map;public class FormulaParser public static List lc = new ArrayList();/ 定义运算符public static List lj = new ArrayList();/ 定义逻辑运算符public static Map funMap = new HashMap();private String formula;static lc.add(+);lc.add();lc.add(*);lc.add(/);lj.add();lj.add();lj.add(=);lj.add(!);/ int数组注释,第一个标识:0自带函数 1自定义函数;第二个标识:参数个数/ 自带函数,可利用反射机制funMap.put(abs, new int 0, 1 );funMap.put(acos, new int 0, 1 );funMap.put(asin, new int 0, 1 );funMap.put(atan, new int 0, 1 );funMap.put(cbrt, new int 0, 1 );funMap.put(ceil, new int 0, 1 );funMap.put(cos, new int 0, 1 );funMap.put(cosh, new int 0, 1 );funMap.put(exp, new int 0, 1 );funMap.put(expm1, new int 0, 1 );funMap.put(floor, new int 0, 1 );funMap.put(log, new int 0, 1 );funMap.put(log10, new int 0, 1 );funMap.put(log1p, new int 0, 1 );funMap.put(random, new int 0, 1 );funMap.put(rint, new int 0, 1 );funMap.put(round, new int 0, 1 );funMap.put(signum, new int 0, 1 );funMap.put(sin, new int 0, 1 );funMap.put(sinh, new int 0, 1 );funMap.put(sqrt, new int 0, 1 );funMap.put(tan, new int 0, 1 );funMap.put(tanh, new int 0, 1 );funMap.put(max, new int 0, 2 );funMap.put(min, new int 0, 2 );/ 自定义函数funMap.put(if, new int 1, 3 );funMap.put(mod, new int 1, 2 );funMap.put(int, new int 1, 1 );public FormulaParser(String str) this.formula = str;/* * 公式初始化转换 * * param str * return */public static String strCast(String str) str = str.toLowerCase();/ 去除空格，变小写if (str = null ? true : str.length() = 0)return 0;if (!checkFormula(str)return 0;str = str.replaceAll(*-, *);str = str.replaceAll(-*, *);str = str.replaceAll(/-, /);str = str.replaceAll(-/, /);str = str.replaceAll(+-, -);str = str.replaceAll(-+, -);str = str.replaceAll(-, );str = str.replaceAll(*, *-);str = str.replaceAll(/, /-);str = str.replaceAll( , );return str;/* * 检查公式中括号出现次数是否正确 * * param formulaStr * return */public static boolean checkFormula(String formulaStr) boolean flag = true;int count = 0;for (int i = 0; i formulaStr.length(); i+) String s = String.valueOf(formulaStr.charAt(i);if (.equals(s)count+;else if ().equals(s)count-;flag = count = 0;return flag;/* * 分割函数 * * param str * param bs * return */public static String spliteFun(String str, String bs) List list = new ArrayList();String bds = ;int bracket = 0;int len = str.length();for (int i = 0; i len; i+) String s = String.valueOf(str.charAt(i);if (.equals(s) bracket+; else if ().equals(s) bracket-;if (bracket = 0 & bs.equals(s) list.add(bds);bds = ;continue;bds += s;list.add(bds);String ss = new Stringlist.size();for (int i = 0; i list.size(); i+) ssi = (String) list.get(i);return ss;/* * 用户自定义函数 * * param str * param funStr * return */public static String customFun(String str, String funStr) String reval = 0;String gss = spliteFun(str, ,);if (if.equals(funStr) if (compare(gss0) reval = calculate(gss1); else reval = calculate(gss2); else if (mod.equals(funStr) double d2 = new Double(calculate(gss1).doubleValue();if (d2 = 0)return reval;double d1 = new Double(calculate(gss0).doubleValue();reval = (d1 % d2) + ; else if (int.equals(funStr) reval = Math.floor(new Double(calculate(gss0).doubleValue()+ ;return reval;/* * 逻辑表达式判断 * * param str * return */public static boolean compare(String str) boolean flag = false;boolean bs = false;int len = str.length();int bracket = 0;String ljbds = ;double d_left = 0;double d_right = 0;for (int i = 0; i len; i+) String s = String.valueOf(str.charAt(i);if (.equals(s) bracket+; else if ().equals(s) bracket-;if (bracket = 0 & lj.contains(s) for (int j = i; j len; j+) String ts = String.valueOf(str.charAt(j);if (lj.contains(ts) ljbds += ts; else bs = true;break;if (bs)break;String s = str.split(ljbds);d_left = new Double(calculate(s0).doubleValue();d_right = new Double(calculate(s1).doubleValue();if (.equals(ljbds) if (d_left .equals(ljbds) if (d_left d_right)return true; else if (=.equals(ljbds) if (d_left = d_right)return true; else if (=.equals(ljbds) if (d_left = d_right)return true; else if (=.equals(ljbds) if (d_left = d_right)return true; else if (.equals(ljbds) | !=.equals(ljbds) if (d_left != d_right)return true;return flag;/* * 递归调用运算 * * param str * return */public static String calculate(String str) String reval = ;String bds = ;int bracket = 0;/ 对应括号个数int pos = 0;boolean title = false;if (str.substring(0, 1).equals() str = str.substring(1);title = true;int len = str.length();for (int i = 0; i len; i+) String s = String.valueOf(str.charAt(i);pos = i;bracket = 0;if (!lc.contains(s) / 如果没遇到运算符if (.equals(s) / 如果遇到左括号if (funMap.containsKey(bds) / 如果左括号前是函数for (int j = i + 1; j len; j+) / 从左括号后开始循环pos+;/ 累计移动字符位数String ts = String.valueOf(str.charAt(j);/ 单个字符/ reval+=ts;if (.equals(ts)/ 如果是左括号累计bracket+;else if ().equals(ts) / 如果是右括号进行减少bracket-;if (bracket = -1) / 如果是-1,标识括号结束reval = reval.substring(0, reval.length()- bds.length();/ 重新获得去掉函数头的表达式reval += funCalculate(str.substring(i + 1,j), bds);/ 表达式加上函数结果,形成新表达式i = pos;/ 计数器增加bds = ;/ 函数头清空break;/ 退出本次循环 else / 如果是普通运算for (int j = i + 1; j len; j+) pos+;String ts = String.valueOf(str.charAt(j);if (.equals(ts)bracket+;else if ().equals(ts) bracket-;if (bracket = -1) reval += calculate(str.substring(i + 1, pos);i = pos;bds = ;break; else / 累加总表达式和最后一个运算数(或函数)bds += s;reval += s; else / 遇到运算符最后一个运算数(或函数)清空bds = ;reval += s;if (title)reval = - + reval;return szys(reval);/* * 函数运算 * * param gs * param flag * return */public static String funCalculate(String gs, String funStr) String rval = 0;if (funMap.containsKey(funStr) int csi = (int) funMap.get(funStr);try if (csi0 = 0) / java内部函数,通过反射调用Class cs = new Classcsi1;Object objs = new Objectcsi1;String gss = zlcs(gs);for (int i = 0; i csi1; i+) csi = double.class;objsi = new Double(calculate(gssi);Class cls = Class.forName(java.lang.Math);Method m = cls.getMethod(funStr, cs);rval = String.valueOf(m.invoke(cls, objs); else if (csi0 = 1) / 自定义函数rval = customFun(gs, funStr); catch (Exception e) return rval;/ 公式里的参数分割public static String zlcs(String str) int len = str.length();boolean flag = true;String tstr = ;for (int i = 0; i len; i+) String s = String.valueOf(str.charAt(i);if (.equals(s) flag = false; else if ().equals(s) flag = true;if (flag & ,.equals(s) tstr += ; else tstr += s;return tstr.split();/* * 四则运算表达式处理 * * param str * return */public static String szys(String gs) gs = gs + +0; / 因为下面的计算是遇到符号才进行,所以多加入一个计算符号,不影响值.String c1 = ;/ 第一个运算符号String c2 = ;/ 第二个运算符号String s1 = ;/ 第一个运算数String s2 = ;/ 第二个运算数String s3 = ;/ 第三个运算数int len = gs.length();for (int i = 0; i 0 & c1.length() 0 & c2.length() = 0) / 如果第一个数,第一个运算符已保存,第二个运算符未保存,保存第二哥数s2 += s; else if (c1.length() = 0) / 如果没有运算符,保存第一个数s1 += s; else if (s1.length() 0 & s2.length() 0 & c1.length() 0& c2.length() 0) / 如果第一二个数和运算符都有,保存第三个数s3 += s;return s1;/* * 基本四则运算 * * param c1 * 运算数1 * param s1 * 运算符(加减乘除) * param c2 * 运算数2 * return */public static String _4zys(String c1, String s1, String c2) String reval = 0;try double ln = Double.valueOf(c1).doubleValue();double rn = Double.valueOf(c2).doubleValue();if (+.equals(s1) return (ln + rn) + ; else if (.equals(s1) return (ln - rn) + ; else if (*.equals(s1) return (ln * rn) + ; else if (/.equals(s1) if (rn = 0)return reval;elsereturn (ln / rn) + ; catch (Exception e) finally return reval;public double getResult() return new Double(calculate(strCast(this.formula).doubleValue();/* * param args */public static void main(String args) / String gs =/ if(4 3,if( ( 2 - 1 ) / ( 0.0001 ) * 3 3 , ( 2 - ( 2 - 1 ) / ( 0.0001 ) * 3 ) * 0.8 ,0), ( 2 + ( 3 - 2 ) / ( 0.0001 ) *1 ) * 1);/ / 进行四则运算获得结果/ System.out.println(szys(strCast(3-4*-5+5);/ / 函数运算结果/ System.out.println(calculate(strCast(3+abs(mod(4,if(23,1,3)-abs(2*4)*5+5);/ / System.out.println(calculate(strCast(if(0.0*2=10.0,0,10.0-0.0*2);/ / System.out.println(calculate(strCast(if(02,(10.0-0*5)*0.8,0);/ / System.out.println(calculate(strCast(gs);System.out.println(calculate(strCast(60.0 / (-100.0) * 50000.0);第2章 计算公式解析运算import java.math.BigDecimal;import java.util.HashMap;import java.util.Map;import java.util.Map.Entry;public class test001 /* * 计算公式解析运算 * author xrxianga * date 2014-8-26 上午06:08:16 */public static void main(String args) throws ExceptionString str = A*B;System.out.println(计算公式：+str);Map map = new HashMap();map.put(A, 11);map.put(B, -22);map.put(C, 33);map.put(D, 44);for(Entry entry:map.entrySet()String val = entry.getValue().toString();if(Double.valueOf(val)0)val = ;str = str.replaceAll(entry.getKey(), val);System.out.println(计算步骤：+str);String a = doReplace(str);/执行计算if(a.startsWith()a = a.substring(1, a.length()-1);System.out.println(计算结果：+a);private static String doReplace(String str)throws ExceptionString src = ,q=,h=;boolean a1 = false;for(int i=0;istr.length();i+)String str1 = str.substring(i, i+1);boolean flag = str1.matches(a-zA-Z0-9(*/-);if(flag)if(.equals(str1)if(a1)q += (;q += src;src = ;a1 = true;continue;else if().equals(str1)h = str.substring(q+src).length()+2,str.length();break;src += str1;if(!.equals(src)src = doCalculate(src);src = q+src+h;if(src.contains()src = doReplace(src);if(!.equals(src)src = doCalculate(src);return src;private static String doCalculate(String str)throws Exceptionif(str.contains(*)/乘str = doCalculate(str, *, /, +, -);if(str.contains(/)/除str = doCalculate(str, /, *, +, -);if(str.contains(-)/减if(doFlag(str)str = doCalculate(str, -, *, /, +);if(str.contains(+)/加str = doCalculate(str, +, *, /, -);return str;private static boolean doFlag(String str)throws ExceptionString a = 0;for(int i=0;istr.length();i+)String val = str.substring(i,i+1);boolean flag = val.matches(a-zA-Z0-9(*/-);if(flag)if(.equals(val)a = 0;continue;if(0.equals(a)&-.equals(val)a = 2;break;if(2.equals(a)return true;return false;private static String doCalculate(String str,String one,String two,String three,String four)throws ExceptionString src = ,q=,h=,g=0;BigDecimal db01 = null;BigDecimal db02 = null;boolean flg01 = false;for(int i=0;istr.length();i+)String val = str.substring(i,i+1);boolean flag = val.matches(a-zA-Z0-9(*/-);if(flag)if(.equals(val)g = 2;if(i+1)=str.length()if(null!=db01)db02 = new BigDecimal(src);h += ;h = str.substring(h.length(), str.length();break;elsereturn str;continue;if(1.equals(g)src += val;continue;if(flg01)if(+.equals(val)|-.equals(val)|/.equals(val)|*.equals(val)db02 = new BigDecimal(src);if(2.equals(g)src = ;g = 0;h += src;h = str.substring(h.length(), str.length();break;else if(i+1)=str.length()src += val;db02 = new BigD