Only use HTTP/2 on certain java versions

Currently we use HTTP/2 as a default but this produces problems with
GOAWAY from servers breaking the download on some buggy JDKs.

For now we disable HTTP/2 on these unsave versions and only enable it
for those where the bug is fixed.

Author: laeubi

providers/bundles/org.eclipse.ecf.provider.filetransfer.httpclientjava/src/org/eclipse/ecf/internal/provider/filetransfer/httpclientjava/ECFHttpClientFactory.java

@@ -16,6 +16,7 @@
 import java.net.Authenticator;
 import java.net.http.HttpClient;
 import java.net.http.HttpClient.Redirect;
+import java.net.http.HttpClient.Version;
 import java.net.http.HttpRequest;
 import java.security.NoSuchAlgorithmException;
 import java.security.NoSuchProviderException;
@@ -51,7 +52,7 @@ public class ECFHttpClientFactory implements IHttpClientFactory {
 
 	@Override
 	public HttpClient.Builder newClient() {
-		HttpClient.Builder builder = HttpClient.newBuilder().followRedirects(Redirect.NORMAL);
+		HttpClient.Builder builder = HttpClient.newBuilder().version(getDefaultHttpVersion()).followRedirects(Redirect.NORMAL);
 		String sslContextProvider = HttpClientOptions.HTTPCLIENT_SSLCONTEXT_PROVIDER;
 		String sslContextProtocol = HttpClientOptions.HTTPCLIENT_SSLCONTEXT_PROTOCOL;
 		SSLContextFactory sslContextFactory = Activator.getDefault().getSSLContextFactory();
@@ -82,6 +83,24 @@ public HttpClient.Builder run(IHttpClientModifier modifier, HttpClient.Builder v
 		return builder;
 	}
 
+	private Version getDefaultHttpVersion() {
+		// See https://bugs.openjdk.org/browse/JDK-8335181
+		// Version with this bug are prone to spurious GOAWAY
+		// So we check here if it is safe to use HTTP/2
+		var version = Runtime.version();
+		int feature = version.feature();
+		if (feature >= 25) {
+			return Version.HTTP_2;
+		}
+		if (feature == 17 && version.compareTo(java.lang.Runtime.Version.parse("17.0.17")) >= 0) {
+			return Version.HTTP_2;
+		}
+		if (feature == 21 && version.compareTo(java.lang.Runtime.Version.parse("21.0.8")) >= 0) {
+			return Version.HTTP_2;
+		}
+		return Version.HTTP_1_1;
+	}
+
 	@Override
 	public IHttpClientContext newClientContext() {
 		IHttpClientContext context = new IHttpClientContext() {