/**
     * 根據(jù)文件路徑讀取文件內(nèi)容
     * @param fileInPath
     * @throws IOException
     */
    public static void getFileContent(Object fileInPath) throws IOException {
        BufferedReader br = null;
        if (fileInPath == null) {
            return;
        }
        if (fileInPath instanceof String) {
            br = new BufferedReader(new FileReader(new File((String) fileInPath)));
        } else if (fileInPath instanceof InputStream) {
            br = new BufferedReader(new InputStreamReader((InputStream) fileInPath));
        }
        String line;
        while ((line = br.readLine()) != null) {
            System.out.println(line);
        }
        br.close();
    }

    public void function1(String fileName) throws IOException {
        String path = this.getClass().getClassLoader().getResource("").getPath();
        //注意getResource("")里面是空字符串
        System.out.println(path);
        String filePath = path + fileName;
        System.out.println(filePath);
        getFileContent(filePath);
    }

    /**
     * 直接通過(guò)文件名getPath來(lái)獲取路徑
     * @param fileName
     * @throws IOException
     */
    public void function2(String fileName) throws IOException {
        String path = this.getClass().getClassLoader().getResource(fileName).getPath();//注意getResource("")里面是空字符串
        System.out.println(path);
        String filePath = URLDecoder.decode(path, "UTF-8");//如果路徑中帶有中文會(huì)被URLEncoder,因此這里需要解碼
        System.out.println(filePath);
        getFileContent(filePath);
    }

url.getFile()=/pub/files/foobar.txt?id=zhouzhou
url.getPath()=/pub/files/foobar.txt

    /**
     * 直接通過(guò)文件名+getFile()來(lái)獲取
     * @param fileName
     * @throws IOException
     */
    public void function3(String fileName) throws IOException {
        String path = this.getClass().getClassLoader().getResource(fileName).getFile();//注意getResource("")里面是空字符串
        System.out.println(path);
        String filePath = URLDecoder.decode(path, "UTF-8");//如果路徑中帶有中文會(huì)被URLEncoder,因此這里需要解碼
        System.out.println(filePath);
        getFileContent(filePath);
    }

    /**
     * 直接使用getResourceAsStream方法獲取流
     * springboot項(xiàng)目中需要使用此種方法，因?yàn)閖ar包中沒(méi)有一個(gè)實(shí)際的路徑存放文件
     * @param fileName
     * @throws IOException
     */
    public void function4(String fileName) throws IOException {
        InputStream in = this.getClass().getClassLoader().getResourceAsStream(fileName);
        getFileContent(in);
    }

    /**
     * 直接使用getResourceAsStream方法獲取流
     * 如果不使用getClassLoader，可以使用getResourceAsStream("/配置測(cè)試.txt")直接從resources根路徑下獲取
     * @param fileName
     * @throws IOException
     */
    public void function5(String fileName) throws IOException {
        InputStream in = this.getClass().getResourceAsStream("/" + fileName);
        getFileContent(in);
    }

    /**
     * 通過(guò)ClassPathResource類獲取，建議SpringBoot中使用
     * springboot項(xiàng)目中需要使用此種方法，因?yàn)閖ar包中沒(méi)有一個(gè)實(shí)際的路徑存放文件
     * @param fileName
     * @throws IOException
     */
    public void function6(String fileName) throws IOException {
        ClassPathResource classPathResource = new ClassPathResource(fileName);
        InputStream inputStream = classPathResource.getInputStream();
        getFileContent(inputStream);
    }

    /**
     * 通過(guò)絕對(duì)路徑獲取項(xiàng)目中文件的位置（不能用于服務(wù)器）
     * @param fileName
     * @throws IOException
     */
    public void function7(String fileName) throws IOException {
        String rootPath = System.getProperty("user.dir");//E:\WorkSpace\Git\spring-framework-learning-example
        String filePath = rootPath + "\\chapter-2-springmvc-quickstart\\src\\main\\resources\\"+fileName;
        getFileContent(filePath);
    }

    /**
     * 通過(guò)絕對(duì)路徑獲取項(xiàng)目中文件的位置（不能用于服務(wù)器）
     * @param fileName
     * @throws IOException
     */
    public void function8(String fileName) throws IOException {
        //參數(shù)為空
        File directory = new File("");
        //規(guī)范路徑：getCanonicalPath() 方法返回絕對(duì)路徑，會(huì)把 ..\ 、.\ 這樣的符號(hào)解析掉
        String rootCanonicalPath = directory.getCanonicalPath();
        //絕對(duì)路徑：getAbsolutePath() 方法返回文件的絕對(duì)路徑，如果構(gòu)造的時(shí)候是全路徑就直接返回全路徑，如果構(gòu)造時(shí)是相對(duì)路徑，就返回當(dāng)前目錄的路徑 + 構(gòu)造 File 對(duì)象時(shí)的路徑
        String rootAbsolutePath =directory.getAbsolutePath();
        System.out.println(rootCanonicalPath);
        System.out.println(rootAbsolutePath);
        String filePath = rootCanonicalPath + "\\chapter-2-springmvc-quickstart\\src\\main\\resources\\"+fileName;
        getFileContent(filePath);
    }

 System.getenv("TEST_ROOT");
 System.getProperty("TEST_ROOT")

    /**
     * 通過(guò)絕對(duì)路徑獲取項(xiàng)目中文件的位置
     * @param fileName
     * @throws IOException
     */
    public void function9(String fileName) throws IOException {
        System.setProperty("TEST_ROOT","E:\\WorkSpace\\Git\\spring-framework-learning-example");
        //參數(shù)為空
        String rootPath = System.getProperty("TEST_ROOT");
        System.out.println(rootPath);
        String filePath = rootPath + "\\chapter-2-springmvc-quickstart\\src\\main\\resources\\"+fileName;
        getFileContent(filePath);
    }