SONAR-6366 add ServletContext to Pico container

ServletContext will be used in an incoming commit to retrieve the Ruby runtime from Rack
in ServerTester, added a dummy ServletContext implementation that supports attributes

server/sonar-server/src/main/java/org/sonar/server/platform/Platform.java

@@ -19,12 +19,13 @@
  */
 package org.sonar.server.platform;
 
-import org.sonar.api.utils.log.Loggers;
 import org.sonar.api.platform.ComponentContainer;
 import org.sonar.api.platform.Server;
+import org.sonar.api.utils.log.Loggers;
 import org.sonar.core.persistence.DatabaseVersion;
 
 import javax.annotation.CheckForNull;
+import javax.servlet.ServletContext;
 import java.util.Collection;
 import java.util.Properties;
 
@@ -66,8 +67,8 @@ public static <T> T component(Class<T> type) {
     return null;
   }
 
-  public void init(Properties properties) {
-    serverComponents = new ServerComponents(this, properties);
+  public void init(Properties properties, ServletContext servletContext) {
+    serverComponents = new ServerComponents(this, properties, servletContext);
     if (!dbConnected) {
       startLevel1Container();
       startLevel2Container();

server/sonar-server/src/main/java/org/sonar/server/platform/PlatformServletContextListener.java

@@ -24,7 +24,6 @@
 import javax.servlet.ServletContext;
 import javax.servlet.ServletContextEvent;
 import javax.servlet.ServletContextListener;
-
 import java.util.Enumeration;
 import java.util.Properties;
 
@@ -34,13 +33,13 @@ public final class PlatformServletContextListener implements ServletContextListe
   public void contextInitialized(ServletContextEvent event) {
     try {
       Properties props = new Properties();
-      ServletContext context = event.getServletContext();
-      Enumeration<String> paramKeys = context.getInitParameterNames();
+      ServletContext servletContext = event.getServletContext();
+      Enumeration<String> paramKeys = servletContext.getInitParameterNames();
       while (paramKeys.hasMoreElements()) {
         String key = paramKeys.nextElement();
-        props.put(key, context.getInitParameter(key));
+        props.put(key, servletContext.getInitParameter(key));
       }
-      Platform.getInstance().init(props);
+      Platform.getInstance().init(props, servletContext);
       Platform.getInstance().doStart();
     } catch (Throwable t) {
       // Tomcat 7 "limitations":
@@ -64,4 +63,5 @@ private void stopQuietly() {
   public void contextDestroyed(ServletContextEvent event) {
     Platform.getInstance().doStop();
   }
+
 }

server/sonar-server/src/main/java/org/sonar/server/platform/ServerComponents.java

@@ -204,26 +204,32 @@
 import org.sonar.server.ws.ListingWs;
 import org.sonar.server.ws.WebServiceEngine;
 
+import javax.annotation.Nullable;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.List;
 import java.util.Properties;
 
 class ServerComponents {
 
-  private final Object[] rootComponents;
-  private List level4AddedComponents = Lists.newArrayList();
+  private final Platform platform;
+  private final Properties properties;
+  @Nullable
+  private final Object[] extraRootComponents;
+  private final List<Object> level4AddedComponents = Lists.newArrayList();
 
-  ServerComponents(Platform platform, Properties properties, Object... rootComponents) {
-    this.rootComponents = Lists.newArrayList(properties, platform, rootComponents)
-      .toArray(new Object[rootComponents.length + 2]);
+  ServerComponents(Platform platform, Properties properties, Object... extraRootComponents) {
+    this.platform = platform;
+    this.properties = properties;
+    this.extraRootComponents = extraRootComponents;
   }
 
   /**
    * All the stuff required to connect to database
    */
-  Collection level1Components() {
-    List components = Lists.newArrayList(rootComponents);
+  Collection<?> level1Components() {
+    List<Object> components = Lists.newArrayList(platform, properties);
+    addExtraRootComponents(components);
     components.addAll(Arrays.asList(
       ServerSettings.class,
       ServerImpl.class,
@@ -297,12 +303,22 @@ Collection level1Components() {
     return components;
   }
 
+  private void addExtraRootComponents(List<Object> components) {
+    if (this.extraRootComponents != null) {
+      for (Object extraRootComponent : this.extraRootComponents) {
+        if (extraRootComponent != null) {
+          components.add(extraRootComponent);
+        }
+      }
+    }
+  }
+
   /**
    * The stuff required to display the db upgrade form in webapp.
    * Needs to be connected to db.
    */
-  Collection level2Components() {
-    return Lists.newArrayList(
+  Collection<Object> level2Components() {
+    return Lists.<Object>newArrayList(
       DefaultServerUpgradeStatus.class,
       DatabaseMigrator.class,
 
@@ -326,7 +342,7 @@ Collection level2Components() {
    * The core components that complete the initialization of database
    * when its schema is up-to-date.
    */
-  Collection level3Components() {
+  Collection<Object> level3Components() {
     return Lists.newArrayList(
       PersistentSettings.class,
       DefaultDatabaseConnector.class,