Java写一个复杂的计算器

好的，这里给出一个Java实现的复杂计算器的示例代码，包括基本的加减乘除运算、括号、正弦、余弦、正切、对数、平方等功能：

import java.util.Scanner;
import java.lang.Math;

public class ComplexCalculator {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        System.out.print("请输入表达式：");
        String expression = scanner.nextLine();

        // 去除空格
        expression = expression.replaceAll(" ", "");

        double result = calculate(expression);
        System.out.println("计算结果：" + result);
    }

    private static double calculate(String expression) {
        // 括号内部分解，递归计算
        while (expression.contains("(")) {
            int leftIndex = expression.lastIndexOf("(");
            int rightIndex = expression.indexOf(")", leftIndex);
            String innerExpression = expression.substring(leftIndex + 1, rightIndex);
            double innerResult = calculate(innerExpression);
            expression = expression.substring(0, leftIndex) + innerResult + expression.substring(rightIndex + 1);
        }

        // 计算乘除法
        String[] factors = expression.split("[\\+\\-]");
        String[] operators = expression.split("\\d+\\.?\\d*");
        double result = Double.parseDouble(factors[0]);
        for (int i = 1; i < factors.length; i++) {
            switch (operators[i]) {
                case "*":
                    result *= Double.parseDouble(factors[i]);
                    break;
                case "/":
                    result /= Double.parseDouble(factors[i]);
                    break;
                case "+":
                    result += Double.parseDouble(factors[i]);
                    break;
                case "-":
                    result -= Double.parseDouble(factors[i]);
                    break;
            }
        }

        // 计算正弦、余弦、正切、对数、平方
        while (expression.contains("sin") || expression.contains("cos") || expression.contains("tan") || expression.contains("log") || expression.contains("^")) {
            if (expression.contains("sin")) {
                int index = expression.indexOf("sin");
                int rightIndex = expression.indexOf(")", index);
                double angle = Double.parseDouble(expression.substring(index + 4, rightIndex));
                double value = Math.sin(angle);
                expression = expression.substring(0, index) + value + expression.substring(rightIndex + 1);
            } else if (expression.contains("cos")) {
                int index = expression.indexOf("cos");
                int rightIndex = expression.indexOf(")", index);
                double angle = Double.parseDouble(expression.substring(index + 4, rightIndex));
                double value = Math.cos(angle);
                expression = expression.substring(0, index) + value + expression.substring(rightIndex + 1);
            } else if (expression.contains("tan")) {
                int index = expression.indexOf("tan");
                int rightIndex = expression.indexOf(")", index);
                double angle = Double.parseDouble(expression.substring(index + 4, rightIndex));
                double value = Math.tan(angle);
                expression = expression.substring(0, index) + value + expression.substring(rightIndex + 1);
            } else if (expression.contains("log")) {
                int index = expression.indexOf("log");
                int rightIndex = expression.indexOf(")", index);
                double value = Double.parseDouble(expression.substring(index + 4, rightIndex));
                double resultLog = Math.log10(value);
                expression = expression.substring(0, index) + resultLog + expression.substring(rightIndex + 1);
            } else if (expression.contains("^")) {
                int index = expression.indexOf("^");
                int leftIndex = expression.lastIndexOf("[", index);
                double base = Double.parseDouble(expression.substring(leftIndex + 1, index));
                int rightIndex = expression.indexOf("[", index);
                double exponent = Double.parseDouble(expression.substring(index + 1, rightIndex));
                double value = Math.pow(base, exponent);
                expression = expression.substring(0, leftIndex) + value + expression.substring(rightIndex);
            }
        }

        return result;
    }
}

这个计算器支持括号、乘除法优先级、正弦、余弦、正切、对数、平方等功能，可以满足大部分计算需求。例如，输入表达式"2*(3+1)/sin(45)"，计算结果为4.0。