看这个:http://docs.oracle.com/javase/6/docs/api/java/util/Properties.html#load(java.io.Reader)

属性接受Reader对象作为参数，您可以从InputStream创建该对象。

在创建时，你可以指定Reader的编码:

InputStreamReader isr = new InputStreamReader(stream, "UTF-8");

然后将这个Reader应用到load方法:

prop.load(isr);

顺便说一句:从.properties文件中获取流:

 InputStream stream = this.class.getClassLoader().getResourceAsStream("a.properties");

顺便说一句:从InputStreamReader获取资源包:

ResourceBundle rb = new PropertyResourceBundle(isr);

希望这能帮助到你!

打开设置/首选项对话框(Ctrl + Alt + S)，然后单击编辑器和文件编码。

然后，在底部，您将找到属性文件的默认编码。选择您的编码类型。

或者，您可以在资源包中使用unicode符号而不是文本(例如“ів”等于\u0456\u0432)

对于当前(2021-2)Java版本，仍然有旧的ISO-8859-1函数utils.Properties#load。

如果您使用属性。装载时必须使用ISO-8859-1。 如果使用ResourceBundle，那么UTF-8应该没问题。

请允许我引用官方文件。

PropertyResourceBundle

PropertyResourceBundle can be constructed either from an InputStream or a Reader, which represents a property file. Constructing a PropertyResourceBundle instance from an InputStream requires that the input stream be encoded in UTF-8. By default, if a MalformedInputException or an UnmappableCharacterException occurs on reading the input stream, then the PropertyResourceBundle instance resets to the state before the exception, re-reads the input stream in ISO-8859-1, and continues reading. If the system property java.util.PropertyResourceBundle.encoding is set to either "ISO-8859-1" or "UTF-8", the input stream is solely read in that encoding, and throws the exception if it encounters an invalid sequence. If "ISO-8859-1" is specified, characters that cannot be represented in ISO-8859-1 encoding must be represented by Unicode Escapes as defined in section 3.3 of The Java™ Language Specification whereas the other constructor which takes a Reader does not have that limitation. Other encoding values are ignored for this system property. The system property is read and evaluated when initializing this class. Changing or removing the property has no effect after the initialization.

https://docs.oracle.com/en/java/javase/14/docs/api/java.base/java/util/PropertyResourceBundle.html

属性#负载

从输入字节流中读取属性列表(键和元素对)。输入流采用load(Reader)中指定的简单的面向行的格式，并假定使用ISO 8859-1字符编码;即每个字节是一个拉丁字符。非拉丁字符1和某些特殊字符使用Java™语言规范3.3节中定义的Unicode转义符在键和元素中表示。

https://docs.oracle.com/en/java/javase/14/docs/api/java.base/java/util/Properties.html加载(java.io.InputStream)

这个问题终于在Java 9中得到了解决: https://docs.oracle.com/javase/9/intl/internationalization-enhancements-jdk-9

属性文件的默认编码现在是UTF-8。

大多数现有属性文件不应受到影响:UTF-8和 ISO-8859-1对ASCII字符有相同的编码 人类可读的非ascii ISO-8859-1编码不是有效的UTF-8。如果一个 检测到无效的UTF-8字节序列，Java运行时 自动重新读取ISO-8859-1中的文件。

As one suggested, i went through implementation of resource bundle.. but that did not help.. as the bundle was always called under en_US locale... i tried to set my default locale to a different language and still my implementation of resource bundle control was being called with en_US... i tried to put log messages and do a step through debug and see if a different local call was being made after i change locale at run time through xhtml and JSF calls... that did not happend... then i tried to do a system set default to a utf8 for reading files by my server (tomcat server).. but that caused pronlem as all my class libraries were not compiled under utf8 and tomcat started to read then in utf8 format and server was not running properly... then i ended up with implementing a method in my java controller to be called from xhtml files.. in that method i did the following:

        public String message(String key, boolean toUTF8) throws Throwable{
            String result = "";
            try{
                FacesContext context = FacesContext.getCurrentInstance();
                String message = context.getApplication().getResourceBundle(context, "messages").getString(key);

                result = message==null ? "" : toUTF8 ? new String(message.getBytes("iso8859-1"), "utf-8") : message;
            }catch(Throwable t){}
            return result;
        }

我特别紧张，因为这可能会降低我应用程序的性能……然而，在实现这个之后，看起来好像我的应用程序现在更快了。我认为这是因为，我现在直接访问属性，而不是让JSF解析其访问属性的方式…我特别在这个调用中传递布尔参数，因为我知道一些属性不会被翻译，不需要在utf8格式…

现在我已经以UTF8格式保存了我的属性文件，它工作正常，因为我的应用程序中的每个用户都有一个引用的区域设置偏好。

从Java 9开始，加载属性文件的默认值已更改为UTF-8。https://docs.oracle.com/javase/9/intl/internationalization-enhancements-jdk-9.htm