本地能获得post请求中的body，为什么打包成war包放在tomcat里就读不到body了？

这个问题可能是由于Tomcat默认使用的是Servlet API的InputStream来读取请求体，而在读取完一次后就无法再读取一次，导致在读取一次后，后续的读取请求体中的数据就为空。

可以尝试使用HttpServletRequestWrapper来包装HttpServletRequest对象，在包装类中重写getReader()和getInputStream()方法来实现多次读取请求体中数据的需求。代码示例如下：

public class MultiReadHttpServletRequest extends HttpServletRequestWrapper {

    private final ByteArrayOutputStream cachedBytes;

    public MultiReadHttpServletRequest(HttpServletRequest request) {
        super(request);
        cachedBytes = new ByteArrayOutputStream();
    }

    @Override
    public ServletInputStream getInputStream() throws IOException {
        if (cachedBytes.size() == 0) {
            return super.getInputStream();
        }
        ByteArrayInputStream input = new ByteArrayInputStream(cachedBytes.toByteArray());
        return new ServletInputStream() {
            public int read() throws IOException {
                return input.read();
            }
        };
    }

    @Override
    public BufferedReader getReader() throws IOException {
        return new BufferedReader(new InputStreamReader(getInputStream()));
    }

    @Override
    public ServletRequest getRequest() {
        return this;
    }

    public void cacheInputStream() throws IOException {
        ServletInputStream inputStream = super.getInputStream();
        byte[] bytes = IOUtils.toByteArray(inputStream);
        cachedBytes.write(bytes);
    }

    public void resetInputStream() {
        cachedBytes.reset();
    }
}

使用时，可以在过滤器中对HttpServletRequest进行包装，如下所示：

public class MultiReadFilter implements Filter {

    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
        if (request.getContentType() != null && request.getContentType().contains("multipart/form-data")) {
            chain.doFilter(request, response);
        } else {
            MultiReadHttpServletRequest multiReadHttpServletRequest = new MultiReadHttpServletRequest((HttpServletRequest) request);
            multiReadHttpServletRequest.cacheInputStream();
            chain.doFilter(multiReadHttpServletRequest, response);
        }
    }

    @Override
    public void init(FilterConfig filterConfig) throws ServletException {}

    @Override
    public void destroy() {}
}

在web.xml文件中配置该过滤器即可实现多次读取请求体中数据的需求。