Java實現讀取項目中文件(.json或.properties)的方法詳解

Posted on by

1. 讀取json file

1.1 Json dependency

        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.76</version>
        </dependency>

1.2 字節流

重點部分

  • . /代表同級目錄
  • …/ 代表上級目錄(兩個點)
  • / 代表根目錄
public class FileService {

    public JSONObject reader(){

        JSONObject resultJson = null;
        String file = "src/main/resources/config_dev.json";
        InputStream is = null;
        try {
            is = new FileInputStream(file);//操作
            byte[] bytes = new byte[5000];//數組容量超級大，一次能將中英混合文本全部讀取完
            int len = -1;
            while ((len = is.read(bytes)) != -1) {
                String str = new String(bytes, 0, len, "UTF-8");
                resultJson = process(str);
            }
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {//釋放資源
            try {
                if (null != is) {
                    is.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        return resultJson;
    }

    private static JSONObject process(String content) {

        JSONObject json = JSONObject.parseObject(content);
        return json;
    }
}

1.3 buffer reader

  public static String reader(String filePath) {
      try {
          File file = new File(filePath);
          if (file.isFile() && file.exists()) {
              InputStreamReader read = new InputStreamReader(new FileInputStream(file), "UTF-8");
              BufferedReader bufferedReader = new BufferedReader(read);
              String lineTxt = bufferedReader.readLine();
              while (lineTxt != null) {
                  return lineTxt;
              }
          }
      } catch (UnsupportedEncodingException | FileNotFoundException e) {
          System.out.println("Cannot find the file specified!");
          e.printStackTrace();
      } catch (IOException e) {
          System.out.println("Error reading file content!");
          e.printStackTrace();
      }
      return null;
  }

2. 讀取properties file

    public void readPropertiesFile() {

        Properties pro = new Properties();

        InputStream is = this.getClass().getResourceAsStream("/application.properties");
        try {
            pro.load(is);

            Enumeration en = pro.propertyNames();

            while (en.hasMoreElements()) {
                String key = (String) en.nextElement();
                String value = pro.getProperty(key);
                System.out.println(key + "--" + value);
            }
        } catch (IOException e) {
            throw new RuntimeException(e);
        }

    }

3. 好看的css樣式

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<link rel="stylesheet" href="https://qxhut.cn/zb_users/plugin/Jz52_click/click.css">
<script src="https://qxhut.cn/zb_users/plugin/Jz52_click/click.js"></script>
<h1>Click Style</h1>
</body>
</html>

到此這篇關於Java實現讀取項目中文件(.json或.properties)的方法詳解的文章就介紹到這瞭,更多相關Java讀取項目文件內容請搜索WalkonNet以前的文章或繼續瀏覽下面的相關文章希望大傢以後多多支持WalkonNet！

推薦閱讀：