java - 多次读取属性文件是否占用大量内存？

Question

我有一个读取属性文件的类。请看下面。应用程序运行时多次调用readProperties()方法，是不是这里内存有问题？

public class PropertyReader {
    private static Properties   configKeyValuePairs         = null;
    private static String       configPropertiesFileName    = "Config.properties";

    static void readProperties() throws FileNotFoundException, IOException {    
        configKeyValuePairs = new Properties();
        InputStream input = ConfigReader.class
                .getResourceAsStream(configPropertiesFileName);

        configKeyValuePairs.load(input);

        input.close();
    }

   static String getUserName(){
       //return user name which is from the properties file.    
    }
}

Answer 1

假设您的属性文件永远不会更改，您可以执行以下操作:

public class MyApplicationConfiguration {
    private static Properties   configKeyValuePairs         = new Properties();
    private static String       configPropertiesFileName    = "Config.properties";

    static {
        InputStream input = null;
        try {
            input = MyApplicationConfiguration.class
                .getResourceAsStream(configPropertiesFileName);

            configKeyValuePairs.load(input);

        } catch (IOException e) {
            // Deal with not being able to load config, could be a fatal error!
        } finally {
            if (input != null) {
                input.close();
            }
        }
    }

    public static String getUsername() {
        // ...
    }

    // Implement getters for other configuration key-value pairs
    // DO NOT let configKeyValuePairs be returned to anyone
}