Spring Boot 基础

说明

该计算工具设有一个主页，随后前往输入页面
用户可在该输入页面输入想计算的四则运算式子，格式为“第一个参与运算的数字（仅限整数及小数）+运算符号（加减乘除）+第二个数字”，如果输入不符合格式，会提示“请正确输入”
系统计算完后呈现结果

如果输入数字过大，会将int转换为long类型
（int上限为2的32次幂，为防止该项目运算两数相乘时出现问题，将阈值设为2的16次幂）

学习过程

wiki文档

创建project时要选maven
根据功能分包、分class
可改输入地址，注意对应url
利用idea辅助纠错功能

作业过程

1.分析需求

实现四则运算，用户输入一个式子（或依次输入三个参数，二选一），需提取、识别出其中的运算符号（加减乘除四段代码），算完后返回
controller写整体框架 计算写到service

由于对具体路线 框架缺乏把握，所以开始搜索

2.网络资料

在bing搜索到了github上的这一篇
[Github上的一个计算器]（https://github.com/jackie-d/simple-calculator）
（下次直接去github搜

打开查看源代码，尝试理解各部分含义。这个计算器还加入了用户登录、历史记录等功能。我在这一份代码的基础上参考、删改、增加等等等等

main controller(类名为Main) 整体流程、框架
'''java

@Autowired
MainService mainService;

//输入要算的式子

@RequestMapping(value="/solve/{number1}/{sign}/{number2}", method = RequestMethod.GET)
public ResponseEntity solveEquation(
        @PathVariable("number1") String number11,
        @PathVariable("sign") String sign,
        @PathVariable("number2") String number21,
        @RequestHeader(value="client-token", required=false) String clientToken
) {
    boolean isInputAcceptable = isInputAcceptable(number1, number2, sign); //输入是否合规

    if (!isInputAcceptable) {
        return ("请正确输入");
    }

    (String number1, String number2, String sign){
        return isIntNumber(number1) && isIntNumber(number2) && isValidSign(sign);
    }

    private boolean isIntNumber (String value){
        try {
            Integer.valueOf(value);
        } catch (NumberFormatException e) {
            return false;
        }
        return true;
    }

    private boolean isValidSign (String value){
        return Equation.SignSymbols.values().contains(value);
    }
    private Equation getEquationSolution (String number1, String number2, String signSymbol){
        int int1 = Integer.valueOf(number1);
        int int2 = Integer.valueOf(number2);

        //调用另一个类里的加减乘除

        Equation.Sign sign = Equation.getSignBySymbol(signSymbol);
        double result = 0;
        switch (sign) {
            case PLUS:
                result = MainService.add(int1, int2);
                break;
            case MINUS:
                result = MainService.subtract(int1, int2);
                break;
            case MULTIPLICATION:
                result = MainService.multiply(int1, int2);
                break;
            case DIVISION:
                result = MainService.divide(int1, int2);
                break;
        }

        Equation solution = new Equation(int1, int2, sign, result);

        return solution;
    }
}

'''

主页
'''java

@GetMapping
public String Home() {
    return "forward:/index.html";
}

}

'''

service 计算部分都放在这里了
'''java
package com.example.spring.Service;

import org.springframework.stereotype.Service;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestParam;

@Service

public class MainService {

//计算
        public double add(int number1, int number2) {
            return Double.valueOf(number1) + Double.valueOf(number2);
        }

        public double subtract(int number1, int number2) {
            return Double.valueOf(number1) - Double.valueOf(number2);
        }

        public double multiply(int number1, int number2) {
            return Double.valueOf(number1) * Double.valueOf(number2);
        }

        public double divide(int number1, int number2) {
            return Double.valueOf(number1) / Double.valueOf(number2);
        }

    }

'''

Equation 一个用来各种“等量代换”、形式转换、数据传递等等的类
'''java
@Entity
public class Equation {

//字符传递、转换
public enum Sign {PLUS, MINUS, MULTIPLICATION, DIVISION};

// map for casting between char symbol representation and enum value

final public static HashMap SignSymbols = new HashMap() {{
    put(Sign.PLUS, "+");
    put(Sign.MINUS, "-");
    put(Sign.MULTIPLICATION, "x");
    put(Sign.DIVISION, "/");
}};

@GeneratedValue
private int number11;
private int number21;
private Sign sign = null;
private String signSymbol = null;
private double result;

if(number11>=pow(2,16)){
    long number1 = number11;
}else if(number21>=pow(2,16)){
    long number2 = number21;
}else{
    int number1 = number11;
    int number2 = number21;
}

public Equation( int number1, int number2, Sign sign,double resultn){

        this.number1 = number1;
        this.number2 = number2;
        this.sign = sign;
        this.signSymbol = this.SignSymbols.get(sign);
        this.result = result;

    }

public Equation(  int number1, int number2, Sign sign,double result ){

        this.number1 = number1;
        this.number2 = number2;
        this.sign = sign;
        this.signSymbol = this.SignSymbols.get(sign);
        this.result = result;
    }

public Equation( int number1, int number2, Sign sign,double result ){

        this.number2 = number2;
        this.sign = sign;
        this.signSymbol = this.SignSymbols.get(sign);
        this.result = result;
    }

public Equation( int number1, int number2, Sign sign ){
        this.number1 = number1;
        this.number2 = number2;
        this.sign = sign;
        this.signSymbol = this.SignSymbols.get(sign);
    }

public int getNumber1() {
    return number1;
}

public void setNumber1(int number1) {
    this.number1 = number1;
}

public int getNumber2() {
    return number2;
}

public void setNumber2(int number2) {
    this.number2 = number2;
}

public Sign getSign() {
    return sign;
}

public void setSign(Sign sign) {
    this.sign = sign;
    this.signSymbol = this.SignSymbols.get(sign);
}

public double getResult() {
    return result;
}

public void setResult(double result) {
    this.result = result;
}

public String getSignSymbol() {
    return signSymbol;
}

public void setSignSymbol(String signSymbol) {
    this.signSymbol = signSymbol;
    this.sign = getSignBySymbol(signSymbol);
}

}
'''

PS.查到了一个似乎是四则运算计算器前端的代码
https://github.com/lihualu0208/comit-caculator/tree/master

蔺涵霖