多平台统一管理软件接口，如何实现多平台统一管理软件接口
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2023-01-25
java代码执行字符串中的逻辑运算方法
java代码执行字符串中的逻辑运算方法
方式一
public class Test
{
public static void main(String[] args) throws Exception {
String str = "(a or b) and c";
str = str.replaceAll("or", "||");
str = str.replaceAll("and", "&&");
System.out.println(str);
ScriptEngineManager manager = new ScriptEngineManager();
ScriptEngine engine = manager.getEngineByName("js");
engine.put("a",true);
engine.put("b",false);
engine.put("c",true);
Object result = engine.eval_r(str);
System.out.println("结果类型:" + result.getClass().getName() + ",计算结果:" + result);
}
}
这种方式使用js的方式进行运算，使用较简单，但是当运算double类型的四则运算时结果会出现循环小数,运算结果会出现问题.
方式二(能够保证四则运算精度):
/**
* @Project: BizRule
* @File: org.coffeesweet.util.MathExpress.java
* @Author: coffeesweet
* @Date: 2011-3-28
* @Description: 2011 coffeesweet Inc. All rights reserved.
*/
package org.coffeesweet.util;
import java.math.BigDecimal;
import java.math.MathContext;
import java.math.RoundingMode;
import java.util.ArrayList;
import java.util.LinkedList;
import java.util.List;
import java.util.StringTokenizer;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
/**
* @author coffeesweet
* +,-,*,/四则运算的表达式逆波兰解析计算类,精确计算,应用BigDecimal类处理
* 支持负数,但规范除整个表达式第一个数为负数时可以不出现在'('后，其它表达式中间任何位置的
* 负数必须出现在'('后,即：用括号括起来。比如：-3+(-2+1)*10或-3+((-2)+1)*10或(-3)+(-2+1)*10或(-3)+((-2)+1)*10
*/
public class MathExpress {
/**
* +
*/
private final static String OP1 = "+";
/**
* -
*/
private final static String OP2 = "-";
/**
* *
*/
private final static String OP3 = "*";
/**
* /
*/
private final static String OP4 = "/";
/**
* ^
*/
// private final static String OP5 = "^";
/**
* %
*/
// private final static String OP6 = "%";
/**
* (
*/
private final static String OPSTART = "(";
/**
* )
*/
private final static String OPEND = ")";
/**
* !用来替代负数前面的'-'
*/
// private final static String NEGATIVESING = "!";
/**
* !用来替代负数前面的'+'
*/
// private final static String PLUSSING = "@";
/**
* '#'用来代表运算级别最低的特殊字符
*/
// private final static String LOWESTSING = "#";
//最原始的四则运算式
private String expBase;
//经过初始化处理后的四则运算式
private String expInited;
//精度
private int precision=10;
//取舍模式
private RoundingMode roundingMode=RoundingMode.HALF_UP;
//精度上下文
private MathContext mc;
//四则运算解析
private List
//存放逆波兰表达式
private List
public MathExpress(){
}
public MathExpress(String expBase) {
init(expBase,this.precision,this.roundingMode);
}
public MathExpress(String expBase,int precision,RoundingMode roundingMode){
init(expBase,precision,roundingMode);
}
public void init(String expBase,int precision,RoundingMode roundingMode){
this.expBase = expBase;
this.precision = precision;
this.roundingMode = roundingMode;
this.mc = new MathContext(precision,roundingMode);
this.expInited = initExpress(expBase);
StringTokenizer st = new StringTokenizer(this.expInited,"+-*/^%()",true);
while(st.hasMoreElements()){
this.expList.add(st.nextElement().toString().trim());
}
this.rpnList = initRPN(this.expList);
}
/**
* @return the expBase
*/
public String getExpBase() {
return expBase;
}
/**
* @param expBase the expBase to set
*/
public void setExpBase(String expBase) {
this.expBase = expBase;
}
/**
* @return the expInited
*/
public String getExpInited() {
return expInited;
}
/**
* @param expInited the expInited to set
*/
public void setExpInited(String expInited) {
this.expInited = expInited;
}
/**
* @return the precision
*/
public int getPrecision() {
return precision;
}
/**
* @param precision the precision to set
*/
public void setPrecision(int precision) {
this.precision = precision;
}
/**
* @return the roundingMode
*/
public RoundingMode getRoundingMode() {
return roundingMode;
}
/**
* @param roundingMode the roundingMode to set
*/
public void setRoundingMode(RoundingMode roundingMode) {
this.roundingMode = roundingMode;
}
/**
* @return the expList
*/
public List
return expList;
}
/**
* @param expList the expList to set
*/
public void setExpList(List
this.expList = expList;
}
/**
* @return the rpnList
*/
public List
return rpnList;
}
/**
* @param rpnList the rpnList to set
*/
public void setRpnList(List
this.rpnList = rpnList;
}
/**
* @return the mc
*/
public MathContext getMc() {
return mc;
}
/**
* @param mc the mc to set
*/
public void setMc(MathContext mc) {
this.mc = mc;
}
/**
* 去除空白字符和在负号'-'前加'0',便于后面的StringTokenizer
* @param exp
* @return
*/
private static String initExpress(String exp){
String reStr = null;
reStr = exp.replaceAll("\\s", "");
if(reStr.startsWith("-")){
reStr = "0"+reStr;
}
reStr = reStr.replaceAll("\\(\\-", "(0-");
return reStr;
}
/**
* 是否是整数或是浮点数,但默认-05.15这种也认为是正确的格式
* @param str
* @return
*/
private boolean isNumber(String str){
Pattern p = Pattern.compile("^(-?\\d+)(\\.\\d+)?$");
Matcher m = p.matcher(str);
boolean isNumber = m.matches();
return isNumber;
}
/**
* 设置优先级顺序()设置与否无所谓
* @param sign
* @return
*/
private int precedence(String str){
char sign = str.charAt(0);
switch(sign){
case '+':
case '-':
return 1;
case '*':
case '/':
return 2;
case '^':
case '%':
return 3;
case '(':
case ')':
// case '#':
default:
return 0;
}
}
/**
* 转变为逆波兰表达式
* @param strList
* @return
*/
public List
List
//用来存放操作符的栈
Stack stack = new Stack();
// stack.push(LOWESTSING);
int length = strList.size();
for(int i=0;i String str = strList.get(i); if(isNumber(str)){ returnList.add(str); }else{ if(str.equals(OPSTART)){ //'('直接入栈 stack.push(str); }else if(str.equals(OPEND)){ //')' //进行出栈操作，直到栈为空或者遇到第一个左括号 while (!stack.isEmpty()) { //将栈顶字符串做出栈操作 String tempC = stack.pop(); if (!tempC.equals(OPSTART)) { //如果不是左括号，则将字符串直接放到逆波兰链表的最后 returnList.add(tempC); }else{ //如果是左括号，退出循环操作 break; } } }else{ if (stack.isEmpty()) { //如果栈内为空 //将当前字符串直接压栈 stack.push(str); }else{ //栈不空,比较运算符优先级顺序 if(precedence(stack.top())>=precedence(str)){ //如果栈顶元素优先级大于当前元素优先级则 while(!stack.isEmpty() && precedence(stack.top())>=precedence(str)){ returnList.add(stack.pop()); } } stack.push(str); } } } } //如果栈不为空，则将栈中所有元素出栈放到逆波兰链表的最后 while (!stack.isEmpty()) { returnList.add(stack.pop()); } return returnList; } /** * 计算逆波兰表达式 * @param rpnList * @return */ public String caculate(List Stack numberStack = new Stack(); int length=rpnList.size(); for(int i=0;i String temp=rpnList.get(i); if(isNumber(temp)){ numberStack.push(temp); }else{ BigDecimal tempNumber1 = new BigDecimal(numberStack.pop(),this.mc); BigDecimal tempNumber2 = new BigDecimal(numberStack.pop(),this.mc); BigDecimal tempNumber = new BigDecimal("0",this.mc); if(temp.equals(OP1)){ tempNumber=tempNumber2.add(tempNumber1); }else if(temp.equals(OP2)){ tempNumber=tempNumber2.subtract(tempNumber1); }else if(temp.equals(OP3)){ tempNumber=tempNumber2.multiply(tempNumber1); }else if(temp.equals(OP4)){ tempNumber=tempNumber2.divide(tempNumber1, precision, roundingMode); } numberStack.push(tempNumber.toString()); } } return numberStack.pop(); } /** * 按照类的缺省参数进行计算 * @return */ public String caculate(){ return caculate(this.rpnList); } /** * 数字条件表达式精确比较 * eg: "3.0>2" "1<5" "1==5" "1!=5" "(1.0+2)>3" "((-0.9+3)>=2. 1)" * 不支持&&,||等连接符 * @param str * @return */ public static boolean compareTo(String strParm){ boolean reBoolean = false; boolean isParentheses = false;//标记是否有()括上整个字符串 String str = initExpress(strParm); Pattern p = Pattern.compile("^\\([\\s\\S]*\\)$"); Matcher m = p.matcher(str); isParentheses = m.matches(); if(-1==str.indexOf(">=")&&-1==str.indexOf("<=")&&-1==str.indexOf("==")&&-1==str.indexOf("!=")){ if(-1==str.indexOf(">")&&-1==str.indexOf("<")) throw new IllegalArgumentException("异常:条件表达式不正确!"); } if(-1 != str.indexOf(">=")){ String[] strTemps = str.split(">="); if(isParentheses){ strTemps[0] = strTemps[0] + ")"; strTemps[1] = "(" + strTemps[1]; } int r = new BigDecimal((new MathExpress(strTemps[0]).caculate())).compareTo(new BigDecimal((new MathExpress(strTemps[1]).caculate()))); if( -1 == r ){ reBoolean = false; }else{ reBoolean = true; } }else if(-1 != str.indexOf("<=")){ String[] strTemphttp://s = str.split("<="); if(isParentheses){ strTemps[0] = strTemps[0] + ")"; strTemps[1] = "(" + strTemps[1]; } int r = new BigDecimal((new MathExpress(strTemps[0]).caculate())).compareTo(new BigDecimal((new MathExpress(strTemps[1]).caculate()))); if( 1 == r ){ reBoolean = false; }else{ reBoolean = true; } }else if(-1 != str.indexOf("==")){ String[] strTemps = str.split("=="); if(isParentheses){ strTemps[0] = strTemps[0] + ")"; strTemps[1] = "(" + strTemps[1]; } int r = new BigDecimal((new MathExpress(strTemps[0]).caculate())).compareTo(new BigDecimal((new MathExpress(strTemps[1]).caculate()))); if( 0 == r ){ reBoolean = true; }else{ reBoolean = false; } }else if(-1 != str.indexOf("!=")){ String[] strTemps = str.split("!="); if(isParentheses){ strTemps[0] = strTemps[0] + ")"; strTemps[1] = "(" + strTemps[1]; } int r = new BigDecimal((new MathExpress(strTemps[0]).caculate())).compareTo(new BigDecimal((new MathExpress(strTemps[1]).caculate()))); if( 0 != r ){ reBoolean = true; }else{ reBoolean = false; } }else if((-1 != str.indexOf(">")) && (-1 == str.indexOf("="))){ String[] strTemps = str.split(">"); if(isParentheses){ strTemps[0] = strTemps[0] + ")"; strTemps[1] = "(" + strTemps[1]; } int r = new BigDecimal((new MathExpress(strTemps[0]).caculate())).compareTo(new BigDecimal((new MathExpress(strTemps[1]).caculate()))); if( 1 == r ){ reBoolean = true; }else{ reBoolean = false; } }else if((-1 != str.indexOf("<")) && (-1 == str.indexOf("="))){ String[] strTemps = str.split("<"); if(isParentheses){ strTemps[0] = strTemps[0] + ")"; strTemps[1] = "(" + strTemps[1]; } int r = new BigDecimal((new MathExpress(strTemps[0]).caculate())).compareTo(new BigDecimal((new MathExpress(strTemps[1]).caculate()))); if( -1 == r ){ reBoolean = true; }else{ reBoolean = false; } } return reBoolean; } public static void main(String...args){ // MathExpress me = new MathExpress("-(-0.5+0.1)*10+2",10,RoundingMode.HALF_UP); // System.out.println(me.getExpList()); // List // System.out.println(tempList); // String resultStr = me.caculate(tempList); // System.out.println(resultStr); MathExpress me = new MathExpress("-(-1.5000000003+0.1)*10+2"); String resultStr = me.caculate(); BigDecimal bd = new BigDecimal(resultStr); BigDecimal bd2 = bd.setScale(2, RoundingMode.HALF_UP); System.out.println(me.caculate()); System.out.println(bd.toString()); System.out.println(bd.scale()); System.out.println(bd2.toString()); System.out.println(bd2.scale()); // System.out.println("------------------------------------"); // Pattern p = Pattern.compile("^\\([\\s\\S]*\\)$");//匹配类似以'('开头')'结尾的字符串 // Matcher m = p.matcher("(2. 0>2.22)"); // System.out.println(m.matches()); boolean reBoolean = MathExpress.compareTo("((-8.0+3)>=2. 1)"); System.out.println(reBoolean); } /** * 栈 */ private class Stack { LinkedList public Stack() { } /** * 入栈 * @param expression */ public void push(String expression) { stackList.addLast(expression); } /** * 出栈 * @return */ public String pop() { return stackList.removeLast(); } /** * 栈顶元素 * @return */ public String top() { return stackList.getLast(); } /** * 栈是否为空 * @return */ public boolean isEmpty() { return stackList.isEmpty(); } } }
String str = strList.get(i);
if(isNumber(str)){
returnList.add(str);
}else{
if(str.equals(OPSTART)){
//'('直接入栈
stack.push(str);
}else if(str.equals(OPEND)){
//')'
//进行出栈操作，直到栈为空或者遇到第一个左括号
while (!stack.isEmpty()) {
//将栈顶字符串做出栈操作
String tempC = stack.pop();
if (!tempC.equals(OPSTART)) {
//如果不是左括号，则将字符串直接放到逆波兰链表的最后
returnList.add(tempC);
}else{
//如果是左括号，退出循环操作
break;
}
}
}else{
if (stack.isEmpty()) {
//如果栈内为空
//将当前字符串直接压栈
stack.push(str);
}else{
//栈不空,比较运算符优先级顺序
if(precedence(stack.top())>=precedence(str)){
//如果栈顶元素优先级大于当前元素优先级则
while(!stack.isEmpty() && precedence(stack.top())>=precedence(str)){
returnList.add(stack.pop());
}
}
stack.push(str);
}
}
}
}
//如果栈不为空，则将栈中所有元素出栈放到逆波兰链表的最后
while (!stack.isEmpty()) {
returnList.add(stack.pop());
}
return returnList;
}
/**
* 计算逆波兰表达式
* @param rpnList
* @return
*/
public String caculate(List
Stack numberStack = new Stack();
int length=rpnList.size();
for(int i=0;i String temp=rpnList.get(i); if(isNumber(temp)){ numberStack.push(temp); }else{ BigDecimal tempNumber1 = new BigDecimal(numberStack.pop(),this.mc); BigDecimal tempNumber2 = new BigDecimal(numberStack.pop(),this.mc); BigDecimal tempNumber = new BigDecimal("0",this.mc); if(temp.equals(OP1)){ tempNumber=tempNumber2.add(tempNumber1); }else if(temp.equals(OP2)){ tempNumber=tempNumber2.subtract(tempNumber1); }else if(temp.equals(OP3)){ tempNumber=tempNumber2.multiply(tempNumber1); }else if(temp.equals(OP4)){ tempNumber=tempNumber2.divide(tempNumber1, precision, roundingMode); } numberStack.push(tempNumber.toString()); } } return numberStack.pop(); } /** * 按照类的缺省参数进行计算 * @return */ public String caculate(){ return caculate(this.rpnList); } /** * 数字条件表达式精确比较 * eg: "3.0>2" "1<5" "1==5" "1!=5" "(1.0+2)>3" "((-0.9+3)>=2. 1)" * 不支持&&,||等连接符 * @param str * @return */ public static boolean compareTo(String strParm){ boolean reBoolean = false; boolean isParentheses = false;//标记是否有()括上整个字符串 String str = initExpress(strParm); Pattern p = Pattern.compile("^\\([\\s\\S]*\\)$"); Matcher m = p.matcher(str); isParentheses = m.matches(); if(-1==str.indexOf(">=")&&-1==str.indexOf("<=")&&-1==str.indexOf("==")&&-1==str.indexOf("!=")){ if(-1==str.indexOf(">")&&-1==str.indexOf("<")) throw new IllegalArgumentException("异常:条件表达式不正确!"); } if(-1 != str.indexOf(">=")){ String[] strTemps = str.split(">="); if(isParentheses){ strTemps[0] = strTemps[0] + ")"; strTemps[1] = "(" + strTemps[1]; } int r = new BigDecimal((new MathExpress(strTemps[0]).caculate())).compareTo(new BigDecimal((new MathExpress(strTemps[1]).caculate()))); if( -1 == r ){ reBoolean = false; }else{ reBoolean = true; } }else if(-1 != str.indexOf("<=")){ String[] strTemphttp://s = str.split("<="); if(isParentheses){ strTemps[0] = strTemps[0] + ")"; strTemps[1] = "(" + strTemps[1]; } int r = new BigDecimal((new MathExpress(strTemps[0]).caculate())).compareTo(new BigDecimal((new MathExpress(strTemps[1]).caculate()))); if( 1 == r ){ reBoolean = false; }else{ reBoolean = true; } }else if(-1 != str.indexOf("==")){ String[] strTemps = str.split("=="); if(isParentheses){ strTemps[0] = strTemps[0] + ")"; strTemps[1] = "(" + strTemps[1]; } int r = new BigDecimal((new MathExpress(strTemps[0]).caculate())).compareTo(new BigDecimal((new MathExpress(strTemps[1]).caculate()))); if( 0 == r ){ reBoolean = true; }else{ reBoolean = false; } }else if(-1 != str.indexOf("!=")){ String[] strTemps = str.split("!="); if(isParentheses){ strTemps[0] = strTemps[0] + ")"; strTemps[1] = "(" + strTemps[1]; } int r = new BigDecimal((new MathExpress(strTemps[0]).caculate())).compareTo(new BigDecimal((new MathExpress(strTemps[1]).caculate()))); if( 0 != r ){ reBoolean = true; }else{ reBoolean = false; } }else if((-1 != str.indexOf(">")) && (-1 == str.indexOf("="))){ String[] strTemps = str.split(">"); if(isParentheses){ strTemps[0] = strTemps[0] + ")"; strTemps[1] = "(" + strTemps[1]; } int r = new BigDecimal((new MathExpress(strTemps[0]).caculate())).compareTo(new BigDecimal((new MathExpress(strTemps[1]).caculate()))); if( 1 == r ){ reBoolean = true; }else{ reBoolean = false; } }else if((-1 != str.indexOf("<")) && (-1 == str.indexOf("="))){ String[] strTemps = str.split("<"); if(isParentheses){ strTemps[0] = strTemps[0] + ")"; strTemps[1] = "(" + strTemps[1]; } int r = new BigDecimal((new MathExpress(strTemps[0]).caculate())).compareTo(new BigDecimal((new MathExpress(strTemps[1]).caculate()))); if( -1 == r ){ reBoolean = true; }else{ reBoolean = false; } } return reBoolean; } public static void main(String...args){ // MathExpress me = new MathExpress("-(-0.5+0.1)*10+2",10,RoundingMode.HALF_UP); // System.out.println(me.getExpList()); // List // System.out.println(tempList); // String resultStr = me.caculate(tempList); // System.out.println(resultStr); MathExpress me = new MathExpress("-(-1.5000000003+0.1)*10+2"); String resultStr = me.caculate(); BigDecimal bd = new BigDecimal(resultStr); BigDecimal bd2 = bd.setScale(2, RoundingMode.HALF_UP); System.out.println(me.caculate()); System.out.println(bd.toString()); System.out.println(bd.scale()); System.out.println(bd2.toString()); System.out.println(bd2.scale()); // System.out.println("------------------------------------"); // Pattern p = Pattern.compile("^\\([\\s\\S]*\\)$");//匹配类似以'('开头')'结尾的字符串 // Matcher m = p.matcher("(2. 0>2.22)"); // System.out.println(m.matches()); boolean reBoolean = MathExpress.compareTo("((-8.0+3)>=2. 1)"); System.out.println(reBoolean); } /** * 栈 */ private class Stack { LinkedList public Stack() { } /** * 入栈 * @param expression */ public void push(String expression) { stackList.addLast(expression); } /** * 出栈 * @return */ public String pop() { return stackList.removeLast(); } /** * 栈顶元素 * @return */ public String top() { return stackList.getLast(); } /** * 栈是否为空 * @return */ public boolean isEmpty() { return stackList.isEmpty(); } } }
String temp=rpnList.get(i);
if(isNumber(temp)){
numberStack.push(temp);
}else{
BigDecimal tempNumber1 = new BigDecimal(numberStack.pop(),this.mc);
BigDecimal tempNumber2 = new BigDecimal(numberStack.pop(),this.mc);
BigDecimal tempNumber = new BigDecimal("0",this.mc);
if(temp.equals(OP1)){
tempNumber=tempNumber2.add(tempNumber1);
}else if(temp.equals(OP2)){
tempNumber=tempNumber2.subtract(tempNumber1);
}else if(temp.equals(OP3)){
tempNumber=tempNumber2.multiply(tempNumber1);
}else if(temp.equals(OP4)){
tempNumber=tempNumber2.divide(tempNumber1,
precision,
roundingMode);
}
numberStack.push(tempNumber.toString());
}
}
return numberStack.pop();
}
/**
* 按照类的缺省参数进行计算
* @return
*/
public String caculate(){
return caculate(this.rpnList);
}
/**
* 数字条件表达式精确比较
* eg: "3.0>2" "1<5" "1==5" "1!=5" "(1.0+2)>3" "((-0.9+3)>=2. 1)"
* 不支持&&,||等连接符
* @param str
* @return
*/
public static boolean compareTo(String strParm){
boolean reBoolean = false;
boolean isParentheses = false;//标记是否有()括上整个字符串
String str = initExpress(strParm);
Pattern p = Pattern.compile("^\\([\\s\\S]*\\)$");
Matcher m = p.matcher(str);
isParentheses = m.matches();
if(-1==str.indexOf(">=")&&-1==str.indexOf("<=")&&-1==str.indexOf("==")&&-1==str.indexOf("!=")){
if(-1==str.indexOf(">")&&-1==str.indexOf("<"))
throw new IllegalArgumentException("异常:条件表达式不正确!");
}
if(-1 != str.indexOf(">=")){
String[] strTemps = str.split(">=");
if(isParentheses){
strTemps[0] = strTemps[0] + ")";
strTemps[1] = "(" + strTemps[1];
}
int r = new BigDecimal((new MathExpress(strTemps[0]).caculate())).compareTo(new BigDecimal((new MathExpress(strTemps[1]).caculate())));
if( -1 == r ){
reBoolean = false;
}else{
reBoolean = true;
}
}else if(-1 != str.indexOf("<=")){
String[] strTemphttp://s = str.split("<=");
if(isParentheses){
strTemps[0] = strTemps[0] + ")";
strTemps[1] = "(" + strTemps[1];
}
int r = new BigDecimal((new MathExpress(strTemps[0]).caculate())).compareTo(new BigDecimal((new MathExpress(strTemps[1]).caculate())));
if( 1 == r ){
reBoolean = false;
}else{
reBoolean = true;
}
}else if(-1 != str.indexOf("==")){
String[] strTemps = str.split("==");
if(isParentheses){
strTemps[0] = strTemps[0] + ")";
strTemps[1] = "(" + strTemps[1];
}
int r = new BigDecimal((new MathExpress(strTemps[0]).caculate())).compareTo(new BigDecimal((new MathExpress(strTemps[1]).caculate())));
if( 0 == r ){
reBoolean = true;
}else{
reBoolean = false;
}
}else if(-1 != str.indexOf("!=")){
String[] strTemps = str.split("!=");
if(isParentheses){
strTemps[0] = strTemps[0] + ")";
strTemps[1] = "(" + strTemps[1];
}
int r = new BigDecimal((new MathExpress(strTemps[0]).caculate())).compareTo(new BigDecimal((new MathExpress(strTemps[1]).caculate())));
if( 0 != r ){
reBoolean = true;
}else{
reBoolean = false;
}
}else if((-1 != str.indexOf(">")) && (-1 == str.indexOf("="))){
String[] strTemps = str.split(">");
if(isParentheses){
strTemps[0] = strTemps[0] + ")";
strTemps[1] = "(" + strTemps[1];
}
int r = new BigDecimal((new MathExpress(strTemps[0]).caculate())).compareTo(new BigDecimal((new MathExpress(strTemps[1]).caculate())));
if( 1 == r ){
reBoolean = true;
}else{
reBoolean = false;
}
}else if((-1 != str.indexOf("<")) && (-1 == str.indexOf("="))){
String[] strTemps = str.split("<");
if(isParentheses){
strTemps[0] = strTemps[0] + ")";
strTemps[1] = "(" + strTemps[1];
}
int r = new BigDecimal((new MathExpress(strTemps[0]).caculate())).compareTo(new BigDecimal((new MathExpress(strTemps[1]).caculate())));
if( -1 == r ){
reBoolean = true;
}else{
reBoolean = false;
}
}
return reBoolean;
}
public static void main(String...args){
// MathExpress me = new MathExpress("-(-0.5+0.1)*10+2",10,RoundingMode.HALF_UP);
// System.out.println(me.getExpList());
// List
// System.out.println(tempList);
// String resultStr = me.caculate(tempList);
// System.out.println(resultStr);
MathExpress me = new MathExpress("-(-1.5000000003+0.1)*10+2");
String resultStr = me.caculate();
BigDecimal bd = new BigDecimal(resultStr);
BigDecimal bd2 = bd.setScale(2, RoundingMode.HALF_UP);
System.out.println(me.caculate());
System.out.println(bd.toString());
System.out.println(bd.scale());
System.out.println(bd2.toString());
System.out.println(bd2.scale());
// System.out.println("------------------------------------");
// Pattern p = Pattern.compile("^\\([\\s\\S]*\\)$");//匹配类似以'('开头')'结尾的字符串
// Matcher m = p.matcher("(2. 0>2.22)");
// System.out.println(m.matches());
boolean reBoolean = MathExpress.compareTo("((-8.0+3)>=2. 1)");
System.out.println(reBoolean);
}
/**
* 栈
*/
private class Stack {
LinkedList
public Stack() {
}
/**
* 入栈
* @param expression
*/
public void push(String expression) {
stackList.addLast(expression);
}
/**
* 出栈
* @return
*/
public String pop() {
return stackList.removeLast();
}
/**
* 栈顶元素
* @return
*/
public String top() {
return stackList.getLast();
}
/**
* 栈是否为空
* @return
*/
public boolean isEmpty() {
return stackList.isEmpty();
}
}
}
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