是否可以在资源包中包含资源包文件

Question

我们java.util.ResourceBundle用来加载属性信息.我们的属性文件变得如此庞大,我们正在考虑将主属性文件拆分为多个子模块.是否有可能实现这一目标？

master.properties

==> 

 master.properties
   include moduleA.properties
   include moduleB.properties

让我知道？

Answer 1

首先,我想知道你为什么选择java.util.ResourceBundle了java.util.Properties.鉴于您的问题是如何制定的,您似乎并不关心本地化/国际化,也不关心包文件继承.

随着Properties它的非凡的容易,因为它实现Map这反过来又提供了一个putAll()合并其他地图的方法.开球示例:

Properties master = new Properties();
master.load(masterInput);

Properties moduleA = new Properties();
moduleA.load(moduleAinput);
master.putAll(moduleA);

Properties moduleB = new Properties();
moduleB.load(moduleBinput);
master.putAll(moduleB);

// Now `master` contains the properties of all files.

如果您真的坚持使用ResourceBundle,最好的办法是创建一个自定义ResourceBundle的自定义装置Control.

假设您有以下条目,master.properties其中表示带有模块属性文件基本名称的逗号分隔字符串:

include=moduleA,moduleB

然后以下自定义ResourceBundle示例应该工作:

public class MultiResourceBundle extends ResourceBundle {

    protected static final Control CONTROL = new MultiResourceBundleControl();
    private Properties properties;

    public MultiResourceBundle(String baseName) {
        setParent(ResourceBundle.getBundle(baseName, CONTROL));
    }

    protected MultiResourceBundle(Properties properties) {
        this.properties = properties;
    }

    @Override
    protected Object handleGetObject(String key) {
        return properties != null ? properties.get(key) : parent.getObject(key);
    }

    @Override
    @SuppressWarnings("unchecked")
    public Enumeration<String> getKeys() {
        return properties != null ? (Enumeration<String>) properties.propertyNames() : parent.getKeys();
    }

    protected static class MultiResourceBundleControl extends Control {
        @Override
        public ResourceBundle newBundle(
            String baseName, Locale locale, String format, ClassLoader loader, boolean reload)
                throws IllegalAccessException, InstantiationException, IOException
        {
            Properties properties = load(baseName, loader);
            String include = properties.getProperty("include");
            if (include != null) {
                for (String includeBaseName : include.split("\\s*,\\s*")) {
                    properties.putAll(load(includeBaseName, loader));
                }
            }
            return new MultiResourceBundle(properties);
        }

        private Properties load(String baseName, ClassLoader loader) throws IOException {
            Properties properties = new Properties();
            properties.load(loader.getResourceAsStream(baseName + ".properties"));
            return properties;
        }
    }

}

(琐碎的异常处理和本地化处理被放在一边,这取决于你)

这可以用作:

ResourceBundle bundle = new MultiResourceBundle("master");