Fix classloading error in host identifier (#9931)

* #9784 avoid NoClassDefFoundError if host resolving failed

just retry it when it's asked next time.

* #9784 catch Errors too

Unfortunately, I don't know what error happened there, but I guess we also need to catch it.

* log the error when resolving host name/address

* #9784 log InterruptedException

I think this really happens sometimes, and causes NoClassDefFoundError in WebDriverException.

Fixes #9784

Author: asolntsev

java/src/org/openqa/selenium/WebDriverException.java

@@ -32,9 +32,6 @@ public class WebDriverException extends RuntimeException {
   public static final String DRIVER_INFO = "Driver info";
   protected static final String BASE_SUPPORT_URL = "https://selenium.dev/exceptions/";
 
-  private static final String HOST_NAME = HostIdentifier.getHostName();
-  private static final String HOST_ADDRESS = HostIdentifier.getHostAddress();
-
   private final Map<String, String> extraInfo = new ConcurrentHashMap<>();
 
   public WebDriverException() {
@@ -72,7 +69,6 @@ public String getMessage() {
    * Returns the simple message string of this exception.
    *
    * @return the simple message string of this exception.
-   *
    * @see #getMessage()
    */
   public String getRawMessage() {
@@ -96,7 +92,7 @@ private String createMessage(String originalMessageString) {
   public String getSystemInformation() {
     return String.format(
       "System info: host: '%s', ip: '%s', os.name: '%s', os.arch: '%s', os.version: '%s', java.version: '%s'",
-      HOST_NAME, HOST_ADDRESS,
+      HostIdentifier.getHostName(), HostIdentifier.getHostAddress(),
       System.getProperty("os.name"), System.getProperty("os.arch"),
       System.getProperty("os.version"), System.getProperty("java.version"));
   }

java/src/org/openqa/selenium/net/HostIdentifier.java

@@ -17,6 +17,8 @@
 
 package org.openqa.selenium.net;
 
+import static java.util.logging.Level.WARNING;
+
 import org.openqa.selenium.Platform;
 
 import java.io.BufferedReader;
@@ -26,12 +28,16 @@
 import java.nio.charset.Charset;
 import java.util.Enumeration;
 import java.util.concurrent.TimeUnit;
+import java.util.logging.Level;
+import java.util.logging.Logger;
 
 public class HostIdentifier {
-  private static final String HOST_NAME;
-  private static final String HOST_ADDRESS;
+  private static final Logger log = Logger.getLogger(HostIdentifier.class.getName());
+
+  private static volatile String hostName;
+  private static volatile String hostAddress;
 
-  static {
+  private static String resolveHostName() {
     // Ideally, we'd use InetAddress.getLocalHost, but this does a reverse DNS lookup. On Windows
     // and Linux this is apparently pretty fast, so we don't get random hangs. On OS X it's
     // amazingly slow. That's less than ideal. Figure things out and cache.
@@ -49,29 +55,35 @@ public class HostIdentifier {
           process.waitFor(2, TimeUnit.SECONDS);
         }
         if (process.exitValue() == 0) {
-          try (InputStreamReader isr = new InputStreamReader(process.getInputStream(), Charset.defaultCharset());
+          try (InputStreamReader isr = new InputStreamReader(process.getInputStream(),
+                                                             Charset.defaultCharset());
                BufferedReader reader = new BufferedReader(isr)) {
             host = reader.readLine();
           }
         }
       } catch (InterruptedException e) {
+        log.log(WARNING, "Failed to resolve host name", e);
         Thread.currentThread().interrupt();
         throw new RuntimeException(e);
-      } catch (Exception e) {
+      } catch (Throwable e) {
         // fall through
+        log.log(WARNING, "Failed to resolve host name", e);
       }
     }
     if (host == null) {
       // Give up.
       try {
         host = InetAddress.getLocalHost().getHostName();
-      } catch (Exception e) {
+      } catch (Throwable e) {
         host = "Unknown";  // At least we tried.
+        log.log(WARNING, "Failed to resolve host name", e);
       }
     }
 
-    HOST_NAME = host;
+    return host;
+  }
 
+  private static String resolveHostAddress() {
     String address = null;
     // Now for the IP address. We're going to do silly shenanigans on OS X only.
     if (Platform.getCurrent().is(Platform.MAC)) {
@@ -81,27 +93,35 @@ public class HostIdentifier {
         if (addresses.hasMoreElements()) {
           address = addresses.nextElement().getHostAddress();
         }
-      } catch (Exception e) {
+      } catch (Throwable e) {
         // Fall through and go the slow way.
+        log.log(WARNING, "Failed to resolve host address", e);
       }
     }
     if (address == null) {
       // Alright. I give up.
       try {
         address = InetAddress.getLocalHost().getHostAddress();
-      } catch (Exception e) {
+      } catch (Throwable e) {
         address = "Unknown";
+        log.log(WARNING, "Failed to resolve host address", e);
       }
     }
 
-    HOST_ADDRESS = address;
+    return address;
   }
 
-  public static String getHostName() {
-    return HOST_NAME;
+  public static synchronized String getHostName() {
+    if (hostName == null) {
+      hostName = resolveHostName();
+    }
+    return hostName;
   }
 
-  public static String getHostAddress() {
-    return HOST_ADDRESS;
+  public static synchronized String getHostAddress() {
+    if (hostAddress == null) {
+      hostAddress = resolveHostAddress();
+    }
+    return hostAddress;
   }
 }