#1885 - ENH: Add ModuleInfoLoader ... to support automatic registration of entity classes (via generated code using querybean generator)

src/main/java/io/ebean/config/ModuleInfo.java

@@ -0,0 +1,21 @@
+package io.ebean.config;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * Used by generated code to hold entity classes to register with Ebean.
+ */
+@Target({ElementType.TYPE})
+@Retention(RetentionPolicy.RUNTIME)
+public @interface ModuleInfo {
+
+  /**
+   * Returns the entity classes with db name prefix.
+   * <p>
+   * The db name prefix is added to entity classes for non default databases.
+   */
+  String[] entities() default {};
+}

src/main/java/io/ebean/config/ModuleInfoLoader.java

@@ -0,0 +1,19 @@
+package io.ebean.config;
+
+import java.util.List;
+
+/**
+ * Loads and returns entity classes to register with Ebean databases.
+ */
+public interface ModuleInfoLoader {
+
+  /**
+   * Return the entity classes to register with the default DB.
+   */
+  List<Class<?>> entityClasses();
+
+  /**
+   * Return entity classes to register for a named DB (not default DB).
+   */
+  List<Class<?>> entityClassesFor(String dbName);
+}

src/main/java/io/ebean/config/ServerConfig.java

@@ -132,6 +132,15 @@ public class ServerConfig {
 
   private TenantCatalogProvider tenantCatalogProvider;
 
+  /**
+   * When true will load entity classes via ModuleInfoLoader.
+   * <p>
+   * NB: ModuleInfoLoader implementations are generated by querybean generator.
+   * Having this on and registering entity classes means we don't need to manually
+   * write that code or use classpath scanning to find entity classes.
+   */
+  private boolean loadModuleInfo;
+
   /**
    * List of interesting classes such as entities, embedded, ScalarTypes,
    * Listeners, Finders, Controllers etc.
@@ -2276,12 +2285,18 @@ public class ServerConfig {
    *            server.
    */
   public void addClass(Class<?> cls) {
-    if (classes == null) {
-      classes = new ArrayList<>();
-    }
     classes.add(cls);
   }
 
+  /**
+   * Register all the classes (typically entity classes).
+   */
+  public void addAll(List<Class<?>> classList) {
+    if (classList != null && !classList.isEmpty()) {
+      classes.addAll(classList);
+    }
+  }
+
   /**
    * Add a package to search for entities via class path search.
    * <p>
@@ -2289,9 +2304,6 @@ public class ServerConfig {
    * </p>
    */
   public void addPackage(String packageName) {
-    if (packages == null) {
-      packages = new ArrayList<>();
-    }
     packages.add(packageName);
   }
 
@@ -2838,6 +2850,7 @@ public class ServerConfig {
     }
     loadDocStoreSettings(p);
 
+    loadModuleInfo = p.getBoolean("loadModuleInfo", loadModuleInfo);
     maxCallStack = p.getInt("maxCallStack", maxCallStack);
     dumpMetricsOnShutdown = p.getBoolean("dumpMetricsOnShutdown", dumpMetricsOnShutdown);
     dumpMetricsOptions = p.get("dumpMetricsOptions", dumpMetricsOptions);
@@ -2962,20 +2975,20 @@ public class ServerConfig {
       return classes;
     }
 
-    List<Class<?>> classes = new ArrayList<>();
+    List<Class<?>> classList = new ArrayList<>();
 
     String[] split = StringHelper.splitNames(classNames);
     for (String cn : split) {
       if (!"class".equalsIgnoreCase(cn)) {
         try {
-          classes.add(Class.forName(cn));
+          classList.add(Class.forName(cn));
         } catch (ClassNotFoundException e) {
           String msg = "Error registering class [" + cn + "] from [" + classNames + "]";
           throw new RuntimeException(msg, e);
         }
       }
     }
-    return classes;
+    return classList;
   }
 
   private List<String> getSearchList(String searchNames, List<String> defaultValue) {
@@ -3259,6 +3272,17 @@ public class ServerConfig {
     this.dumpMetricsOptions = dumpMetricsOptions;
   }
 
+  /**
+   * Return true if entity classes should be loaded and registered via ModuleInfoLoader.
+   * <p>
+   * When false we either register entity classes via application code or use classpath
+   * scanning to find and register entity classes.
+   * </p>
+   */
+  public boolean isAutoLoadModuleInfo() {
+    return loadModuleInfo && classes.isEmpty();
+  }
+
   public enum UuidVersion {
     VERSION4,
     VERSION1,

src/main/java/io/ebeaninternal/server/core/DefaultContainer.java

@@ -1,6 +1,7 @@
 package io.ebeaninternal.server.core;
 
 import io.ebean.config.ContainerConfig;
+import io.ebean.config.ModuleInfoLoader;
 import io.ebean.config.ServerConfig;
 import io.ebean.config.ServerConfigProvider;
 import io.ebean.config.TenantMode;
@@ -85,11 +86,7 @@ public class DefaultContainer implements SpiContainer {
   public SpiEbeanServer createServer(ServerConfig serverConfig) {
 
     synchronized (this) {
-      if (serverConfig.isDefaultServer()) {
-        for (ServerConfigProvider configProvider : ServiceLoader.load(ServerConfigProvider.class)) {
-          configProvider.apply(serverConfig);
-        }
-      }
+      applyConfigServices(serverConfig);
 
       setNamingConvention(serverConfig);
       BootupClasses bootupClasses = getBootupClasses(serverConfig);
@@ -120,7 +117,6 @@ public class DefaultContainer implements SpiContainer {
 
       // executor and l2 caching service setup early (used during server construction)
       SpiBackgroundExecutor executor = createBackgroundExecutor(serverConfig);
-
       InternalConfiguration c = new InternalConfiguration(online, clusterManager, executor, serverConfig, bootupClasses);
 
       DefaultServer server = new DefaultServer(c, c.cacheManager());
@@ -128,24 +124,45 @@ public class DefaultContainer implements SpiContainer {
       // generate and run DDL if required
       // if there are any other tasks requiring action in their plugins, do them as well
       if (!DbOffline.isGenerateMigration()) {
-        server.executePlugins(online);
-
-        // initialise prior to registering with clusterManager
-        server.initialise();
-        if (online) {
-          if (clusterManager.isClustering()) {
-            // register the server once it has been created
-            clusterManager.registerServer(server);
-          }
-        }
-        // start any services after registering with clusterManager
-        server.start();
+        startServer(online, server);
       }
       DbOffline.reset();
       return server;
     }
   }
 
+  private void applyConfigServices(ServerConfig config) {
+    if (config.isDefaultServer()) {
+      for (ServerConfigProvider configProvider : ServiceLoader.load(ServerConfigProvider.class)) {
+        configProvider.apply(config);
+      }
+      if (config.isAutoLoadModuleInfo()) {
+        // auto register entity classes (default db)
+        for (ModuleInfoLoader loader : ServiceLoader.load(ModuleInfoLoader.class)) {
+          config.addAll(loader.entityClasses());
+        }
+      }
+    } else if (config.isAutoLoadModuleInfo()) {
+      // auto register entity classes (other named db)
+      for (ModuleInfoLoader loader : ServiceLoader.load(ModuleInfoLoader.class)) {
+        config.addAll(loader.entityClassesFor(config.getName()));
+      }
+    }
+  }
+
+  private void startServer(boolean online, DefaultServer server) {
+    server.executePlugins(online);
+    // initialise prior to registering with clusterManager
+    server.initialise();
+    if (online) {
+      if (clusterManager.isClustering()) {
+        clusterManager.registerServer(server);
+      }
+    }
+    // start any services after registering with clusterManager
+    server.start();
+  }
+
   /**
    * Get the entities, scalarTypes, Listeners etc combining the class registered
    * ones with the already created instances.