java Process调用python脚本乱码踩坑记

背景：

项目中需要使用java调用python脚本执行一些操作，于是直接使用的Process调用shell脚本，shell脚本里面执行python的脚本调用。

出现的问题：

突然有一天，测试小姐姐说，python输出的日志中文全是乱码，于是乎...

解决思路：

1、出现乱码的原因:

出现乱码的原因无非就是编码和解码的方式对不上（比如：读用 UTF-8 写用 GB2312）

2、解决的办法

     1）、既然编码对不上，那直接将乱码的编码方式转换一下就行了，但是转码需要知道转换之前和转换之后的编码，python脚本的编码是UTF-8，但是java Process拿到的流的编码是没办法指定的。源码如下：

/**
     * Returns the input stream connected to the normal output of the
     * process.  The stream obtains data piped from the standard
     * output of the process represented by this {@code Process} object.
     *
     * 
If the standard output of the process has been redirected using
     * {@link ProcessBuilder#redirectOutput(Redirect)
     * ProcessBuilder.redirectOutput}
     * then this method will return a
     * null input stream.
     *
     * 
Otherwise, if the standard error of the process has been
     * redirected using
     * {@link ProcessBuilder#redirectErrorStream(boolean)
     * ProcessBuilder.redirectErrorStream}
     * then the input stream returned by this method will receive the
     * merged standard output and the standard error of the process.
     *
     * 
Implementation note: It is a good idea for the returned
     * input stream to be buffered.
     *
     * @return the input stream connected to the normal output of the
     *         process
     */
    public abstract InputStream getInputStream();

    /**
     * Returns the input stream connected to the error output of the
     * process.  The stream obtains data piped from the error output
     * of the process represented by this {@code Process} object.
     *
     * 
If the standard error of the process has been redirected using
     * {@link ProcessBuilder#redirectError(Redirect)
     * ProcessBuilder.redirectError} or
     * {@link ProcessBuilder#redirectErrorStream(boolean)
     * ProcessBuilder.redirectErrorStream}
     * then this method will return a
     * null input stream.
     *
     * 
Implementation note: It is a good idea for the returned
     * input stream to be buffered.
     *
     * @return the input stream connected to the error output of
     *         the process
     */
    public abstract InputStream getErrorStream();

于是在inputstream拿到的流外面指定编码。即如下操作：

BufferedReader reader = new BufferedReader(new InputStreamReader(stream,StandardCharsets.UTF_8)); //指定为UTF-8编码

结果，结果还是不行。后面仔细想想，这样原因是python是UTF-8编码，现在拿到的redader在控制台已经输出了乱码，说明现在的编码已经不是UTF-8,那么再强转成UTF-8肯定依旧是乱码。感觉行不通，换一种解决思路。

2）、查询Process源码的注释，发现一个很有用的信息，如下（本人英语比较差，翻译不好勿怪）

By default, the created process does not have its own terminal
 * or console.  All its standard I/O (i.e. stdin, stdout, stderr)
 * operations will be redirected to the parent process, where they can
 * be accessed via the streams obtained using the methods

大概意思是，创建进程没有自己的控制台，他的所有的标准IO，输入输出，错误的输出都重定向到他的父进程，在父进程的控制台里面可以通过流被访问。父进程，父进程，哈哈，原来Process的编码是由父进程指定的，项目部署在docker里面，于是进入docker容器locale一下，果然没有指定编码，于是修改docker打包方式，指定默认编码为UTF-8乱码解决