add support for language configuration by system property

.gitignore

@@ -1,3 +1,4 @@
+.DS_Store
 .gradle
 .idea
 .classpath

vertx-platform/src/main/java/org/vertx/java/deploy/impl/VerticleManager.java

@@ -137,6 +137,15 @@ public class VerticleManager implements ModuleReloader {
         }
       }
     }
+
+    Set<String> propertyNames = System.getProperties().stringPropertyNames();
+    for (String propertyName : propertyNames) {
+      if (propertyName.startsWith("vertx.langs.")) {
+        String lang = propertyName.replaceFirst("vertx.langs.", "");
+        String value = System.getProperty(propertyName);
+        factoryNames.put(lang, value);
+      }
+    }
   }
 
   public void block() {

vertx-testsuite/src/test/java/org/vertx/java/tests/deploy/FooLangVerticleFactory.java

@@ -0,0 +1,38 @@
+package org.vertx.java.tests.deploy;
+
+import org.vertx.java.core.json.JsonObject;
+import org.vertx.java.deploy.Verticle;
+import org.vertx.java.deploy.impl.VerticleFactory;
+import org.vertx.java.deploy.impl.VerticleManager;
+
+public class FooLangVerticleFactory implements VerticleFactory {
+
+  private VerticleManager manager;
+
+  @Override
+  public void init(VerticleManager manager) {
+    this.manager = manager;
+  }
+
+  @Override
+  public Verticle createVerticle(String main, ClassLoader parentCL)
+      throws Exception {
+
+    return new Verticle() {
+
+      @Override
+      public void start() throws Exception {
+        JsonObject config = manager.getConfig();
+        String foo = config.getString("foo", "bar");
+        if (foo.equalsIgnoreCase("bar")) {
+          throw new Exception("foo must not be bar!");
+        }
+      }};
+  }
+
+  @Override
+  public void reportException(Throwable t) {
+    t.printStackTrace();
+  }
+
+}

vertx-testsuite/src/test/java/org/vertx/java/tests/deploy/SystemPropertyLanguageImplementationTest.java

@@ -0,0 +1,76 @@
+package org.vertx.java.tests.deploy;
+
+import java.io.File;
+import java.net.URL;
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.TimeUnit;
+
+import org.junit.AfterClass;
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.BeforeClass;
+import org.junit.Test;
+import org.vertx.java.core.Handler;
+import org.vertx.java.core.impl.DefaultVertx;
+import org.vertx.java.core.impl.VertxInternal;
+import org.vertx.java.core.json.JsonObject;
+import org.vertx.java.deploy.impl.VerticleManager;
+
+public class SystemPropertyLanguageImplementationTest {
+
+  private VerticleManager verticleManager;
+  private VertxInternal vertxInternal;
+
+  @BeforeClass
+  public static void beforeClass() {
+    System.setProperty("vertx.langs.foo", "org.vertx.java.tests.deploy.FooLangVerticleFactory");
+  }
+
+  @Before
+  public void before() throws Exception {
+    vertxInternal = new DefaultVertx();
+    verticleManager = new VerticleManager(vertxInternal);
+  }
+
+  @Test
+  public void deployFooVerticle() {
+    String main = "test.foo";
+
+    JsonObject config = new JsonObject();
+    config.putString("foo", "foo");
+
+    URL[] urls = new URL[0];
+    File currentModDir = new File(System.getProperty("java.io.tmpdir"));
+    String includes = null;
+
+    final CountDownLatch latch = new CountDownLatch(1);
+    Handler<String> doneHandler = new Handler<String>() {
+      @Override
+      public void handle(String event) {
+        // TODO Auto-generated method stub
+        latch.countDown();
+      }
+    };
+
+    verticleManager.deployVerticle(false, main, config, urls, 1, currentModDir, includes, doneHandler);
+
+    boolean await = false;
+
+    try {
+      await = latch.await(5000L, TimeUnit.MILLISECONDS);
+
+    } catch (InterruptedException e) {
+      // TODO Auto-generated catch block
+      e.printStackTrace();
+    }
+
+    if (!await)  {
+      Assert.fail("Probably not deployed");
+    }
+  }
+
+  @AfterClass
+  public static void cleanup() {
+    System.clearProperty("vertx.langs.foo");
+  }
+}

vertx-testsuite/src/test/resources/META-INF/services/org.vertx.java.deploy.impl.VerticleFactory

@@ -0,0 +1 @@
+org.vertx.java.tests.deploy.FooLangVerticleFactory

vertx-testsuite/src/test/resources/test.foo

@@ -0,0 +1 @@
+// hello