Java InputStream 中文乱码

待我称王封你为后i 2024-03-02 10:33 26阅读 0赞

#### 一、问题描述 ####

在调用 http POST ，获取请求体中的内容时，如果出现中文，在读取的时候，可能会引起“中文乱码”的现象。

如下读取方式 **会** 引起中文乱码：

public XssRequestWrapper(HttpServletRequest request) throws IOException {
        
            super(request);
            this.request = request;
            StringBuilder stringBuilder = new StringBuilder();
            BufferedReader bufferedReader = null;
            try {
        
                InputStream inputStream = request.getInputStream();
                if (inputStream != null) {
        
                    // 如下方式读取 InputStream 流，会引发中文乱码问题
                    bufferedReader = new BufferedReader(new InputStreamReader(inputStream));
                    char[] charBuffer = new char[128];
                    int bytesRead = -1;
                    while ((bytesRead = bufferedReader.read(charBuffer)) > 0) {
        
                        stringBuilder.append(charBuffer, 0, bytesRead);
                    }
                } else {
        
                    stringBuilder.append("");
                }
            } catch (IOException ex) {
        
                throw ex;
            } finally {
        
                if (bufferedReader != null) {
        
                    try {
        
                        bufferedReader.close();
                    } catch (IOException ex) {
        
                        throw ex;
                    }
                }
            }
    
            System.out.println("stringBuilder: " + stringBuilder.toString());
    }

#### 二、问题原因 ####

在不设置编码的情况下，InputStreamReader 默认的读取编码是 ***ASCII* 编码**，**中文会转成乱码**。

#### 三、解决方案 ####

在 InputStreamReader 读取时，需要指定读取的编码格式为 ***UTF\_8* 编码**

如下读取方式 **不会** 引起中文乱码：

public XssRequestWrapper(HttpServletRequest request) throws IOException {
        
            super(request);
            this.request = request;
            StringBuilder stringBuilder = new StringBuilder();
            BufferedReader bufferedReader = null;
            try {
        
                InputStream inputStream = request.getInputStream();
                if (inputStream != null) {
        
                    // 此处需要将编码格式设置为UTF_8，解决 InputStream 流读取时的中文乱码问题
                    bufferedReader = new BufferedReader(new InputStreamReader(inputStream, StandardCharsets.UTF_8));
                    char[] charBuffer = new char[128];
                    int bytesRead = -1;
                    while ((bytesRead = bufferedReader.read(charBuffer)) > 0) {
        
                        stringBuilder.append(charBuffer, 0, bytesRead);
                    }
                } else {
        
                    stringBuilder.append("");
                }
            } catch (IOException ex) {
        
                throw ex;
            } finally {
        
                if (bufferedReader != null) {
        
                    try {
        
                        bufferedReader.close();
                    } catch (IOException ex) {
        
                        throw ex;
                    }
                }
            }
    
            System.out.println("stringBuilder: " + stringBuilder.toString());
    }