java/net/URLConnection/ZeroContentLength.java fails intermittently:

----------System.out:(2/67)----------
**********************************
200 OK, content-length:1024 ...
----------System.err:(63/5074)----------
java.net.ConnectException: Operation timed out (Connection timed out)
at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:488)
at java.base/sun.net.www.protocol.http.HttpURLConnection$10.run(HttpURLConnection.java:1945)
at java.base/sun.net.www.protocol.http.HttpURLConnection$10.run(HttpURLConnection.java:1940)
at java.base/java.security.AccessController.doPrivileged(Native Method)
at java.base/sun.net.www.protocol.http.HttpURLConnection.getChainedException(HttpURLConnection.java:1939)
at java.base/sun.net.www.protocol.http.HttpURLConnection.getInputStream0(HttpURLConnection.java:1507)
at java.base/sun.net.www.protocol.http.HttpURLConnection.access$200(HttpURLConnection.java:97)
at java.base/sun.net.www.protocol.http.HttpURLConnection$9.run(HttpURLConnection.java:1483)
at java.base/sun.net.www.protocol.http.HttpURLConnection$9.run(HttpURLConnection.java:1481)
at java.base/java.security.AccessController.doPrivileged(Native Method)
at java.base/java.security.AccessController.doPrivilegedWithCombiner(AccessController.java:793)
at java.base/sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1480)
at ZeroContentLength.doRequest(ZeroContentLength.java:238)
at ZeroContentLength.<init>(ZeroContentLength.java:282)
at ZeroContentLength.main(ZeroContentLength.java:333)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:564)
at com.sun.javatest.regtest.agent.MainActionHelper$SameVMRunnable.run(MainActionHelper.java:230)
at java.base/java.lang.Thread.run(Thread.java:844)
Caused by: java.net.ConnectException: Operation timed out (Connection timed out)
at java.base/java.net.PlainSocketImpl.socketConnect(Native Method)
at java.base/java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:400)
at java.base/java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:243)
at java.base/java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:225)
at java.base/java.net.Socket.connect(Socket.java:591)
at java.base/java.net.Socket.connect(Socket.java:540)
at java.base/sun.net.NetworkClient.doConnect(NetworkClient.java:182)
at java.base/sun.net.www.http.HttpClient.openServer(HttpClient.java:474)
at java.base/sun.net.www.http.HttpClient.openServer(HttpClient.java:569)
at java.base/sun.net.www.http.HttpClient.&lt;init&gt;(HttpClient.java:242)
at java.base/sun.net.www.http.HttpClient.New(HttpClient.java:341)
at java.base/sun.net.www.http.HttpClient.New(HttpClient.java:362)
at java.base/sun.net.www.protocol.http.HttpURLConnection.getNewHttpClient(HttpURLConnection.java:1224)
at java.base/sun.net.www.protocol.http.HttpURLConnection.plainConnect0(HttpURLConnection.java:1163)
at java.base/sun.net.www.protocol.http.HttpURLConnection$6.run(HttpURLConnection.java:1047)
at java.base/sun.net.www.protocol.http.HttpURLConnection$6.run(HttpURLConnection.java:1045)
at java.base/java.security.AccessController.doPrivileged(Native Method)
at java.base/java.security.AccessController.doPrivilegedWithCombiner(AccessController.java:793)
at java.base/sun.net.www.protocol.http.HttpURLConnection.plainConnect(HttpURLConnection.java:1044)
at java.base/sun.net.www.protocol.http.HttpURLConnection.connect(HttpURLConnection.java:991)
at java.base/sun.net.www.protocol.http.HttpURLConnection.getInputStream0(HttpURLConnection.java:1563)
at java.base/sun.net.www.protocol.http.HttpURLConnection.access$200(HttpURLConnection.java:97)
at java.base/sun.net.www.protocol.http.HttpURLConnection$9.run(HttpURLConnection.java:1483)
at java.base/sun.net.www.protocol.http.HttpURLConnection$9.run(HttpURLConnection.java:1481)
at java.base/java.security.AccessController.doPrivileged(Native Method)
at java.base/java.security.AccessController.doPrivilegedWithCombiner(AccessController.java:793)
at java.base/sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1480)
at java.base/sun.net.www.protocol.http.HttpURLConnection.getHeaderField(HttpURLConnection.java:3015)
at java.base/java.net.URLConnection.getHeaderFieldLong(URLConnection.java:651)
at java.base/java.net.URLConnection.getContentLengthLong(URLConnection.java:523)
at java.base/java.net.URLConnection.getContentLength(URLConnection.java:507)
at ZeroContentLength.doRequest(ZeroContentLength.java:236)
... 8 more