Rework the V3 launcher.

This resolves two issues:

1) The map of possible roles and configs wasn't thread
   safe. It is now.

2) The server could only be started in standalone mode,
   and didn't allow node or hub configs to be started
   from the main.

Author: shs96c

java/server/src/org/openqa/grid/selenium/GridLauncherV3.java

@@ -23,9 +23,8 @@
 
 import org.openqa.grid.common.GridRole;
 import org.openqa.grid.common.RegistrationRequest;
-import org.openqa.grid.common.exception.GridConfigurationException;
-import org.openqa.grid.internal.utils.configuration.GridHubConfiguration;
 import org.openqa.grid.internal.utils.SelfRegisteringRemote;
+import org.openqa.grid.internal.utils.configuration.GridHubConfiguration;
 import org.openqa.grid.internal.utils.configuration.GridNodeConfiguration;
 import org.openqa.grid.internal.utils.configuration.StandaloneConfiguration;
 import org.openqa.grid.shared.CliUtils;
@@ -36,6 +35,8 @@
 
 import java.io.File;
 import java.io.IOException;
+import java.util.Arrays;
+import java.util.function.Supplier;
 import java.util.logging.ConsoleHandler;
 import java.util.logging.FileHandler;
 import java.util.logging.Handler;
@@ -46,52 +47,57 @@ public class GridLauncherV3 {
 
   private static final Logger log = Logger.getLogger(GridLauncherV3.class.getName());
 
-  public static abstract class GridItemLauncher {
-    protected Object configuration;
+  private static abstract class GridItemLauncher {
+    protected StandaloneConfiguration configuration;
+    protected boolean helpRequested;
     abstract void setConfiguration(String[] args);
     abstract void launch() throws Exception;
     void printUsage() {
       new JCommander(configuration).usage();
     }
   }
 
-  private static ImmutableMap<GridRole, GridItemLauncher> launchers
-    = new ImmutableMap.Builder<GridRole, GridItemLauncher>()
-      .put(GridRole.NOT_GRID, new GridItemLauncher() {
+  private static ImmutableMap<GridRole, Supplier<GridItemLauncher>> LAUNCHERS =
+    ImmutableMap.<GridRole, Supplier<GridItemLauncher>>builder()
+      .put(GridRole.NOT_GRID, () -> new GridItemLauncher() {
         public void setConfiguration(String[] args) {
           configuration = new StandaloneConfiguration();
           new JCommander(configuration, args);
+          helpRequested = configuration.help;
         }
+
         public void launch() throws Exception {
           log.info("Launching a standalone Selenium Server");
-          SeleniumServer server = new SeleniumServer((StandaloneConfiguration)configuration);
+          SeleniumServer server = new SeleniumServer(configuration);
           server.boot();
           log.info("Selenium Server is up and running");
         }
       })
-    .put(GridRole.HUB, new GridItemLauncher() {
+    .put(GridRole.HUB, () -> new GridItemLauncher() {
       public void setConfiguration(String[] args) {
         configuration = new GridHubConfiguration();
         new JCommander(configuration, args);
+        helpRequested = configuration.help;
       }
       public void launch() throws Exception {
         log.info("Launching Selenium Grid hub");
-        Hub h = new Hub((GridHubConfiguration)configuration);
+        Hub h = new Hub((GridHubConfiguration) configuration);
         h.start();
         log.info("Nodes should register to " + h.getRegistrationURL());
         log.info("Selenium Grid hub is up and running");
       }
     })
-    .put(GridRole.NODE, new GridItemLauncher() {
+    .put(GridRole.NODE, () -> new GridItemLauncher() {
       public void setConfiguration(String[] args) {
         configuration = new GridNodeConfiguration();
         new JCommander(configuration, args);
+        helpRequested = configuration.help;
       }
       public void launch() throws Exception {
         log.info("Launching a Selenium Grid node");
-        RegistrationRequest c = RegistrationRequest.build((GridNodeConfiguration)configuration);
+        RegistrationRequest c = RegistrationRequest.build((GridNodeConfiguration) configuration);
         SelfRegisteringRemote remote = new SelfRegisteringRemote(c);
-        remote.setRemoteServer(new SeleniumServer((StandaloneConfiguration)configuration));
+        remote.setRemoteServer(new SeleniumServer(configuration));
         remote.startRemoteServer();
         log.info("Selenium Grid node is up and ready to register to the hub");
         remote.startRegistrationProcess();
@@ -100,33 +106,63 @@ public void launch() throws Exception {
     .build();
 
   public static void main(String[] args) throws Exception {
-    StandaloneConfiguration configuration = new StandaloneConfiguration();
-    new JCommander(configuration, args);
-
-    GridRole role = GridRole.get(configuration.role);
-
-    if (role == null) {
-      printInfoAboutRoles(configuration.role);
+    GridItemLauncher launcher = buildLauncher(args);
+    if (launcher == null) {
       return;
     }
 
-    launchers.get(role).setConfiguration(args);
-
-    if (configuration.help) {
-      launchers.get(role).printUsage();
+    if (launcher.helpRequested) {
+      launcher.printUsage();
       return;
     }
 
-    configureLogging(configuration);
+    configureLogging(launcher.configuration);
 
     try {
-      launchers.get(role).launch();
+      launcher.launch();
     } catch (Exception e) {
-      launchers.get(role).printUsage();
+      launcher.printUsage();
       e.printStackTrace();
     }
   }
 
+  /**
+   * From the {@code args}, builds a new {@link GridItemLauncher} and populates it properly.
+   *
+   * @return null if no role is found, or a properly populated {@link GridItemLauncher}.
+   */
+  private static GridItemLauncher buildLauncher(String[] args) {
+    String role = "standalone";
+
+    for (int i = 0; i < args.length; i++) {
+      if (args[i].startsWith("-role=")) {
+        role = args[i].substring("-role=".length());
+      } else if (args[i].equals("-role")) {
+        i++;  // Increment, because we're going to need this.
+        if (i < args.length) {
+          role = args[i];
+        } else {
+          role = null;  // Will cause us to print the usage information.
+        }
+      }
+    }
+
+    GridRole gridRole = GridRole.get(role);
+    if (gridRole == null) {
+      printInfoAboutRoles(role);
+      return null;
+    }
+
+    Supplier<GridItemLauncher> supplier = LAUNCHERS.get(gridRole);
+    if (supplier == null) {
+      System.err.println("Unknown role: " + gridRole);
+      return null;
+    }
+    GridItemLauncher toReturn = supplier.get();
+    toReturn.setConfiguration(args);
+    return toReturn;
+  }
+
   private static void printInfoAboutRoles(String roleCommandLineArg) {
     if (roleCommandLineArg != null) {
       CliUtils.printWrappedLine(