drools规则出现中文验证 与jvm 默认编码（The default charset is determined during virtual-machine）的关系很重要

java.nio.charset.Charset类中有一个静态变量：

 private static volatile Charset defaultCharset;

参考文档说明：http://docs.oracle.com/javase/1.5.0/docs/api/java/nio/charset/Charset.html#defaultCharset()，

Returns the default charset of this Java virtual machine.

The default charset is determined during virtual-machine startup and typically depends upon the locale and charset of the underlying operating system.

 JVM默认的编码要么我们显示设置：-Dfile.encoding=UTF-8 （https://stackoverflow.com/questions/6031877/jvm-property-dfile-encoding-utf8-or-utf-8）

，如果不设置，会依赖当前操作系统的时区和编码。

drools中的规则如果出现中文校验，则我们必须设置编码，以防止校验规则失灵，出现此问题时，经debug到

Charset

类，看到jvm默认的编码对规则校验的失灵发生。

请自己手动验证一下吧。

 注意：以linux 服务方式启动，比如

service mysql start

方式启动自己的java 应用也会出现编码问题。

 具体解决：

https://stackoverflow.com/questions/13415975/cant-read-utf-8-filenames-when-launched-as-an-upstart-service

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Java uses a native call to list the contents of a directory. The underlying C runtime relies on the locale concept to build Java Strings from the byte blob stored by the filesystem as the filename.

When you execute a Java program from a shell (either as a privileged user or an unprivileged one) it carries an environment made of variables. The variable LANG is read to transcode the stream of bytes to a Java String, and by default on Ubuntu it's associated to the UTF-8 encoding.

Note that a process need not to be run from any shell, but looking at the code it seems that Upstart is smart enough to understand when the command in the configuration file is intended to be executed from a shell. So, assuming that the JVM is invoked through a shell, the problem is that the variable LANG is not set, so the C runtime assumes a default charset, which happens to not beUTF-8. The solution is in the Upstart stanza:

description "List UTF-8 encoded filenames"author "Raffaele Sgarro"env LANG=en_US.UTF-8script  cd /workspace  java -jar list.jar test > log.txtend script

I used en_US.UTF-8 as the locale, but any UTF-8 backed one will do just as well. The sources of the test list.jar

public static void main(String[] args) {    for (File file : new File(args[0]).listFiles()) {        System.out.println(file.getName());    }}

The directory /workspace/test contains filenames like ààà, èèè and so on. Now you can move to the database part ;)

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