Question

我试图从属性fie中读取但是它在这里不起作用是我的代码

File configFile = new File("intput.properties");
Properties prop = new Properties();
try
{
    FileReader read = new FileReader(configFile);

    if (income <= 11000)
    {
        tax = Double.parseDouble(prop.getProperty("tax", "0"));
        taxMessage.setText("Annual tax:" + tax);
    }
    read.close();
}
catch (FileNotFoundException ex)
{
}
catch (IOException ex)
{
}

我没有收到任何错误，但它没有显示输出。

Answer 1

您的属性尚未加载。见Properties#load(Reader)

prop.load(read);

您的代码应该是这样的：

File configFile = new File("intput.properties");
Properties prop = new Properties();
try {
    FileReader read = new FileReader(configFile);
    prop.load(read);

    //the if block is not been executed when your income always > 11000 .
    if (income <= 11000) {
        tax = Double.parseDouble(prop.getProperty("tax", "0"));

        taxMessage.setText("Annual tax:" + tax);
    }
    read.close();
} catch (Exception ex) { throw new RuntimeException(ex); }

Answer 2

以下代码可以提供帮助。它是属性文件的位置或导致问题的加载方法。

Properties prop = new Properties();
        InputStream input = null;

        try {

            input = new FileInputStream("C:\\temp\\intput.properties");

            // load a properties file
            prop.load(input);

            // get the property value and print it out
            System.out.println(prop.getProperty("tax"));

        } catch (IOException ex) {
            ex.printStackTrace();
        } finally {
            if (input != null) {
                try {
                    input.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }

从proprties文件中读取java

2 个答案:

您的代码应该是这样的：