[java] Add JSpecify annotations for nullable return types in DriverService

Author: iampopovich

java/src/org/openqa/selenium/remote/BUILD.bazel

@@ -77,6 +77,7 @@ java_library(
         "//java/src/org/openqa/selenium/support/decorators",
         artifact("com.google.guava:guava"),
         artifact("net.bytebuddy:byte-buddy"),
+        artifact("org.jspecify:jspecify"),
     ],
 )
 

java/src/org/openqa/selenium/remote/service/DriverService.java

@@ -49,6 +49,7 @@
 import org.openqa.selenium.net.PortProber;
 import org.openqa.selenium.net.UrlChecker;
 import org.openqa.selenium.os.ExternalProcess;
+import org.jspecify.annotations.Nullable;
 
 /**
  * Manages the life and death of a native executable driver server. It is expected that the driver
@@ -145,15 +146,15 @@ protected Capabilities getDefaultDriverOptions() {
     return new ImmutableCapabilities();
   }
 
-  protected String getDriverName() {
+  protected @Nullable String getDriverName() {
     return null;
   }
 
-  public String getDriverProperty() {
+  public @Nullable String getDriverProperty() {
     return null;
   }
 
-  protected File getDriverExecutable() {
+  protected @Nullable File getDriverExecutable() {
     return null;
   }