Stop using static initializers to look for firefox executables. It is not a frequently used operation to care about performance so much. And static initialization prevents ability to change location specified by a system property after first initialization. Also it prevents ability to find a firefox installed later than selenium server was started.

Author: barancev

java/client/src/org/openqa/selenium/firefox/internal/Executable.java

@@ -34,13 +34,8 @@
 
 /**
  * Wrapper around our runtime environment requirements. Performs discovery of firefox instances.
- *
- * <p>
- * NOTE: System and platform binaries will only be discovered at class initialization.
  */
 public class Executable {
-  private static final File SYSTEM_BINARY = locateFirefoxBinaryFromSystemProperty();
-  private static final File PLATFORM_BINARY = locateFirefoxBinaryFromPlatform();
 
   private final File binary;
 
@@ -58,13 +53,15 @@ public Executable(File userSpecifiedBinaryPath) {
               userSpecifiedBinaryPath);
     }
 
-    if (SYSTEM_BINARY != null && SYSTEM_BINARY.exists()) {
-      binary = SYSTEM_BINARY;
+    File systemBinary = locateFirefoxBinaryFromSystemProperty();
+    if (systemBinary != null) {
+      binary = systemBinary;
       return;
     }
 
-    if (PLATFORM_BINARY != null && PLATFORM_BINARY.exists()) {
-      binary = PLATFORM_BINARY;
+    File platformBinary = locateFirefoxBinaryFromPlatform();
+    if (platformBinary != null) {
+      binary = platformBinary;
       return;
     }