为什么我的 parser.next 扫描仪会选择括号和数字，而不是 i 之前的字符串，尽管有一个分隔符-解网

问：

我正在扫描的文档显示“enter（10）;加;（45.76）“在一行上。它应该阅读括号和分号，只获取数字和字符串，并在运行代码之前阅读单词“enter”。它设法正确读取回车和第一个数字，但之后在扫描“方程式”时，它反而抓住了带有括号的 45.67）。如果我删除（45.67）并留下 add ; 它可以工作并获取添加。我不确定这里出了什么问题。任何帮助将不胜感激，以及有关如何让该程序扫描文件中下一行（如果有另一行）的任何建议。

import java.io.File;
import java.io.FileNotFoundException;
import java.util.InputMismatchException;
import java.util.Scanner;

public class CPLParser {

	public double parseScript(String inputFile) throws CPLException{
		File file = new File(inputFile);
		try (Scanner Filereader = new Scanner(file)){
			String line = Filereader.nextLine();
			Scanner parser = new Scanner(line);
			parser.useDelimiter("\\(|\\)\\;");
			String enter = parser.next();
			double number = 0;
			String equation = " ";
			double numberTwo = 0;
			double total = 0;

			if (!enter.equals("enter")){
				throw new InvalidProgramStartException("");
			}

			while (parser.hasNext()) {
				if (parser.hasNextDouble()){
					number = parser.nextDouble();
				}
				if (parser.hasNext()){
					equation = parser.next();
				}
				if (parser.hasNextDouble()){
					numberTwo = parser.nextDouble();
				}
				if (equation == "add") {
					double thistotal = number + numberTwo;
					total += thistotal;
				}
			}
			System.out.println(equation);




		} catch (FileNotFoundException ex) {
			System.out.println("Could not find the file");
		} catch (InputMismatchException e) {

		}

		return 0;
	}

}

Java java.util.scanner 分隔符

import java.net.MalformedURLException; 
import java.net.URL;
import java.awt.image.*;
import javax.imageio.*;
import javax.swing.*;
import java.io.*;
import java.util.Scanner;

public class Main
{
    public static void main(String[] args) {
        System.out.println("Hello World");
        try {
            Scanner parser = new Scanner("enter(10);add;(45.76)");
            parser.useDelimiter("\\(|\\)|\\;");
            String enter = parser.next();
                System.out.println("enter "+enter);
            double number = 0;
            String equation = " ";
            double numberTwo = 0;
            double total = 0;

            if (!enter.equals("enter")){
                // new InvalidProgramStartException("");
                System.out.println("InvalidProgramStartException");
            }

            while (parser.hasNext()) {
                if (parser.hasNextDouble()){
                    number = parser.nextDouble();
                        System.out.println("number "+ number);
                }
                if (parser.hasNext()){
                    String text= parser.next();
                    // only set equation if its not blank
                    if ("".equals(text))
                    { System.out.println("equation is Blank "+ equation +"...");}
                    else
                    {equation = text;
                    System.out.println("Setting equation "+ equation);}
                }
                if (parser.hasNextDouble()){
                    numberTwo = parser.nextDouble();
                    System.out.println("numberTwo "+ numberTwo);
                }

            }

            if (equation.equals("add")) {
                    double thistotal = number + numberTwo;
                    System.out.println("thistotal "+ thistotal);
                    System.out.println("total "+ total);
                    total += thistotal;
                    System.out.println("total "+ total);
                }
            System.out.println(equation);





        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

希望这有帮助！

为什么我的 parser.next 扫描仪会选择括号和数字，而不是 i 之前的字符串，尽管有一个分隔符

Why is my parser.next scanner picking up on a parenthesis and number instead of the string that comes before i despite having a delimiter

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