线程“main”java中出现异常。木卫一。FileNotFoundException：（系统在请求文件路径时找不到指定的文件）

Question

我有一个java程序，我需要要求用户在他们的计算机中输入一个csv文件路径，然后它应该要求在文件中输入一个特定的字符串，搜索该字符串，然后打印出带有该字符串的所有行。

当我把文件路径硬编码成字符串时，这个程序工作得很好，比如String path="C：\用户\Shinky\ideaProjects\枚举\src\Salmon.csv"，但是一旦我手动输入文件路径，我就会得到：线程“main”中的异常java.io.FileNotFoundExc0019：java.io.FileInputStream@1b6d3586（系统找不到指定的文件）

我尝试将文件直接存储在我的项目下面，也存储在src文件夹中，但每次都会出现相同的错误。在这一点上，我不知道该做什么，或者如果在我的IDE之外请求一个文件路径通常会更容易，任何帮助都将不胜感激。

代码：

import java.io.*;

public class StageReport {

    private static StageReport run;         //StageReport object
    private static FileInputStream path;    //Object path for csv file
    private Stage stage;                    //Object stage
    private static String choice;           //String choice for input
    private static String file;             //String inFile for csv file path input

    /**
     * constructor
     */
    public StageReport(Stage stage){
        this.stage = stage;
    }//end StageReport


    /**
     * finds and outputs correct mortality rates of fish
     */
    public void reader() throws Exception{

        //String path = "C:\\Users\\Shinky\\Desktop\\Salmon.csv";
        String line;

        BufferedReader br = new BufferedReader(new FileReader(String.valueOf(path)));//BufferedReader reads csv file

        //switch for enum Stage class
        switch (stage) {
            case FISH:
                while ((line = br.readLine()) != null) {
                    String[] values = line.split(",");//csv file lines split from ,
                    //searches through file to find stages that correspond with user input and outputs correct year, stage and mortality rate
                    if(values[1].equalsIgnoreCase("Fish Entry")){
                        System.out.println(values[0]+" "+values[1]+" "+values[2]);
                    }

                }
                break;

            case GROW:
                while ((line = br.readLine()) != null) {
                    String[] values = line.split(",");//csv file lines split from ,
                    //searches through file to find stages that correspond with user input and outputs correct year, stage and mortality rate
                    if(values[1].equalsIgnoreCase("Grow-out")){
                        System.out.println(values[0]+" "+values[1]+" "+values[2]);
                    }

                }
                break;

            case HARVESTING:
                while ((line = br.readLine()) != null) {
                    String[] values = line.split(",");//csv file lines split from ,
                    //searches through file to find stages that correspond with user input and outputs correct year, stage and mortality rate
                    if(values[1].equalsIgnoreCase("Harvesting")){
                        System.out.println(values[0]+" "+values[1]+" "+values[2]);
                    }

                }

                break;

            default:
                System.out.println("No valid entries found");//prompt for no entries found in csv file
                break;
        }

    }//end reader

    /**
     * constructor
     */
    public static void main(String[] args) throws Exception{

        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));//BufferedReader declared
        System.out.print("Enter input file path and name: ");
        file = br.readLine();
        System.out.println("You entered: " + file);
        path = new FileInputStream(file);

        System.out.print("Enter the stage you would like to see: ");
        choice = br.readLine();


        //checks if user input matches enum Stage strings
        if (choice.equalsIgnoreCase(String.valueOf(Stage.FISH))) {
            run = new StageReport(Stage.FISH);
            run.reader();
        } else if (choice.equalsIgnoreCase(String.valueOf(Stage.GROW))) {
            run = new StageReport(Stage.GROW);
            run.reader();
        } else
            run = new StageReport(Stage.HARVESTING);
        run.reader();

    }//end main

}//end StageReport

enum Stage{ FISH("Fish Entry"), GROW("Grow-out"), HARVESTING("Harvesting");

    private String name;        //String name for enum names


    /**
     * Sets String names
     * @param name the names of the Strings in the enum classs
     */
    Stage(String name) {
        this.name = name;
    }//end Stage

    @Override
    public String toString() {
        return name;
    }//end String

}//end Stage

Answer 1

试试这个，src文件夹下的给定文件。

 InputStream stream = this.getClass().getResourceAsStream(file);
 BufferedReader br = new BufferedReader(new InputStreamReader(stream));//BufferedReader 
 reads csv file