websocket设置传输大小

tomcat中有提到：

If the application does not define a MessageHandler.Partial for incoming text messages, any incoming text messages must be buffered so the entire message can be delivered in a single call to the registered MessageHandler.
Whole for text messages. The default buffer size for text messages is 8192 bytes. This may be changed for a web application by setting the servlet context initialization parameter org.apache.tomcat.websocket.
textBufferSize to the desired value in bytes.

1、对项目web.xml添加如下配置（注意单位为byte）

<context-param>
    <param-name>org.apache.tomcat.websocket.textBufferSize</param-name>
    <param-value>5242800</param-value>
</context-param>

2、对于spring工程来说这个方法没问题可以生效，但是springboot并没有web.xml该如何解决呢？如下：

@Configuration
@ComponentScan
@EnableAutoConfiguration
public class WebSocketConfig implements ServletContextInitializer{
    
    //配置websocket传输大小，50M
    @Override
    public void onStartup(ServletContext servletContext) throws ServletException {
        servletContext.addListener(WebAppRootListener.class);
        servletContext.setInitParameter("org.apache.tomcat.websocket.textBufferSize","52428800");
        servletContext.setInitParameter("org.apache.tomcat.websocket.binaryBufferSize","52428800");
    }
}

注意：在使用的时候还发现了一个问题，如上配置假如是以springboot内置tomcat启动是没有问题的，但是打成war后使用外置tomcat运行却不生效，最终发现是因为外置tomcat版本问题，出问题的版本是tomcat8.0.xx，而使用tomcat8.5.xx就没有这个问题了

参考链接：https://blog.csdn.net/luohualiushui1/article/details/86596754