support multiple remote groups

java/idea-ui/src/com/intellij/platform/templates/RemoteTemplatesFactory.java

@@ -22,12 +22,15 @@ import com.intellij.openapi.diagnostic.Logger;
 import com.intellij.openapi.extensions.PluginId;
 import com.intellij.openapi.module.ModuleType;
 import com.intellij.openapi.module.ModuleTypeManager;
+import com.intellij.openapi.util.ClearableLazyValue;
 import com.intellij.openapi.util.JDOMUtil;
 import com.intellij.openapi.util.io.StreamUtil;
 import com.intellij.platform.ProjectTemplate;
 import com.intellij.platform.ProjectTemplatesFactory;
+import com.intellij.util.ArrayUtil;
 import com.intellij.util.NullableFunction;
 import com.intellij.util.containers.ContainerUtil;
+import com.intellij.util.containers.MultiMap;
 import com.intellij.util.net.HttpConfigurable;
 import org.jdom.Element;
 import org.jdom.JDOMException;
@@ -37,6 +40,7 @@ import org.jetbrains.annotations.Nullable;
 import java.io.IOException;
 import java.io.InputStream;
 import java.net.HttpURLConnection;
+import java.util.Collection;
 import java.util.List;
 import java.util.zip.ZipInputStream;
 
@@ -47,32 +51,46 @@ import java.util.zip.ZipInputStream;
 public class RemoteTemplatesFactory extends ProjectTemplatesFactory {
 
   private static final String URL = "http://download.jetbrains.com/idea/project_templates/";
+  private static final String SAMPLES_GALLERY = "Samples Gallery";
+  private final ClearableLazyValue<MultiMap<String, ProjectTemplate>> myTemplates = new ClearableLazyValue<MultiMap<String, ProjectTemplate>>() {
+    @NotNull
+    @Override
+    protected MultiMap<String, ProjectTemplate> compute() {
+      return getTemplates();
+    }
+  };
 
   @NotNull
   @Override
   public String[] getGroups() {
-    return new String[] { "Samples Gallery"};
+    myTemplates.drop();
+    return ArrayUtil.toStringArray(myTemplates.getValue().keySet());
   }
 
   @NotNull
   @Override
   public ProjectTemplate[] createTemplates(String group, WizardContext context) {
+    Collection<ProjectTemplate> templates = myTemplates.getValue().get(group);
+    return templates.toArray(new ProjectTemplate[templates.size()]);
+  }
+
+  private static MultiMap<String, ProjectTemplate> getTemplates() {
     InputStream stream = null;
     HttpURLConnection connection = null;
     String code = ApplicationInfo.getInstance().getBuild().getProductCode();
     try {
       connection = getConnection(code + "_templates.xml");
       stream = connection.getInputStream();
-      String text = StreamUtil.readText(stream);
+      String text = StreamUtil.readText(stream, TemplateModuleBuilder.UTF_8);
       return createFromText(text);
     }
     catch (IOException ex) {  // timeouts, lost connection etc
       LOG.info(ex);
-      return ProjectTemplate.EMPTY_ARRAY;
+      return MultiMap.emptyInstance();
     }
     catch (Exception e) {
       LOG.error(e);
-      return ProjectTemplate.EMPTY_ARRAY;
+      return MultiMap.emptyInstance();
     }
     finally {
       StreamUtil.closeStream(stream);
@@ -83,11 +101,28 @@ public class RemoteTemplatesFactory extends ProjectTemplatesFactory {
   }
 
   @SuppressWarnings("unchecked")
-  public static ProjectTemplate[] createFromText(String text) throws IOException, JDOMException {
+  public static MultiMap<String, ProjectTemplate> createFromText(String text) throws IOException, JDOMException {
 
-    List<Element> elements = JDOMUtil.loadDocument(text).getRootElement().getChildren("template");
+    Element rootElement = JDOMUtil.loadDocument(text).getRootElement();
+    List<Element> groups = rootElement.getChildren("group");
+    MultiMap<String, ProjectTemplate> map = new MultiMap<String, ProjectTemplate>();
+    if (groups.isEmpty()) { // sample gallery by default
+      map.put(SAMPLES_GALLERY, createGroupTemplates(rootElement));
+    }
+    else {
+      for (Element group : groups) {
+        map.put(group.getChildText("name"), createGroupTemplates(group));
+      }
+    }
 
-    List<ProjectTemplate> templates = ContainerUtil.mapNotNull(elements, new NullableFunction<Element, ProjectTemplate>() {
+    return map;
+  }
+
+  @SuppressWarnings("unchecked")
+  private static List<ProjectTemplate> createGroupTemplates(Element groupElement) {
+    List<Element> elements = groupElement.getChildren("template");
+
+    return ContainerUtil.mapNotNull(elements, new NullableFunction<Element, ProjectTemplate>() {
       @Override
       public ProjectTemplate fun(final Element element) {
 
@@ -127,7 +162,6 @@ public class RemoteTemplatesFactory extends ProjectTemplatesFactory {
         };
       }
     });
-    return templates.toArray(new ProjectTemplate[templates.size()]);
   }
 
   private static HttpURLConnection getConnection(String path) throws IOException {