当我呼叫响应 StreamingResponseBody 的服务时，下载开始并下载了一些MB，但是一段时间后，它停止了，这就是我的控制台上显示的内容：
2019-07-26 09:52:39.263 ERROR 3924 --- [nio-8080-exec-5] o.a.catalina.connector.CoyoteAdapter : Exception while processing an asynchronous request
java.lang.IllegalStateException: Calling [asyncError()] is not valid for a request with Async state [MUST_DISPATCH]
at org.apache.coyote.AsyncStateMachine.asyncError(AsyncStateMachine.java:440) ~[tomcat-embed-core-9.0.19.jar:9.0.19]
at org.apache.coyote.AbstractProcessor.action(AbstractProcessor.java:512) ~[tomcat-embed-core-9.0.19.jar:9.0.19]
at org.apache.coyote.Request.action(Request.java:430) ~[tomcat-embed-core-9.0.19.jar:9.0.19]
at org.apache.catalina.core.AsyncContextImpl.setErrorState(AsyncContextImpl.java:401) ~[tomcat-embed-core-9.0.19.jar:9.0.19]
at org.apache.catalina.connector.CoyoteAdapter.asyncDispatch(CoyoteAdapter.java:239) ~[tomcat-embed-core-9.0.19.jar:9.0.19]
at org.apache.coyote.AbstractProcessor.dispatch(AbstractProcessor.java:241) ~[tomcat-embed-core-9.0.19.jar:9.0.19]
at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:53) ~[tomcat-embed-core-9.0.19.jar:9.0.19]
at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:836) ~[tomcat-embed-core-9.0.19.jar:9.0.19]
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1747) ~[tomcat-embed-core-9.0.19.jar:9.0.19]
at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) ~[tomcat-embed-core-9.0.19.jar:9.0.19]
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128) ~[na:na]
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628) ~[na:na]
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) ~[tomcat-embed-core-9.0.19.jar:9.0.19]
at java.base/java.lang.Thread.run(Thread.java:834) ~[na:na]
调试我可以看到，最内部的异常是：java.io.IOException：当前线程被中断。
服务代码：
@RestController
@RequestMapping("/")
public class MyController {
@GetMapping("/srbFile")
public ResponseEntity<StreamingResponseBody> srbFile() {
StreamingResponseBody srb = (out) -> {
for (int i = 0; i < 10000000; i++) {
try {
String msg = String.valueOf(i);
out.write(("Hello Every body: " + msg + System.lineSeparator()).getBytes());
out.flush();
} catch (IOException e) {
e.printStackTrace();
}
}
};
return ResponseEntity.ok().contentType(MediaType.APPLICATION_OCTET_STREAM)
.header(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename=data.csv").body(srb);
}
}
在客户端：
一个简单的链接：<a href="/srbFile">Download</a>
环境：
Spring Boot 2.1.5.RELEASE
Java：OpenJdk 11.0.1
感谢前进！