Automatically detect default interpreter for registerHook()

spark/src/main/java/org/apache/zeppelin/spark/ZeppelinContext.java

@@ -716,10 +716,16 @@ public class ZeppelinContext {
   }
 
   /**
-   * Get the interpreter class name from repl name entered in paragraph
-   * @param replName
+   * Get the interpreter class name from name entered in paragraph
+   * @param replName if replName is a valid className, return that instead.
    */
   public String getClassNameFromReplName(String replName) {
+    for (String name : interpreterClassMap.values()) {
+      if (replName.equals(name)) {
+        return replName;
+      }
+    }
+    
     if (replName.contains("spark.")) {
       replName = replName.replace("spark.", "");
     }
@@ -746,8 +752,8 @@ public class ZeppelinContext {
    */
   @Experimental
   public void registerHook(String event, String cmd) {
-    String replName = interpreterContext.getRequiredReplName();
-    registerHook(event, cmd, replName);
+    String className = interpreterContext.getClassName();
+    registerHook(event, cmd, className);
   }
 
   /**
@@ -768,8 +774,8 @@ public class ZeppelinContext {
    */
   @Experimental
   public String getHook(String event) {
-    String replName = interpreterContext.getRequiredReplName();
-    return getHook(event, replName);
+    String className = interpreterContext.getClassName();
+    return getHook(event, className);
   }
 
   /**
@@ -790,8 +796,8 @@ public class ZeppelinContext {
    */
   @Experimental
   public void unregisterHook(String event) {
-    String replName = interpreterContext.getRequiredReplName();
-    unregisterHook(event, replName);
+    String className = interpreterContext.getClassName();
+    unregisterHook(event, className);
   }
 
   /**

zeppelin-interpreter/src/main/java/org/apache/zeppelin/interpreter/InterpreterContext.java

@@ -57,6 +57,7 @@ public class InterpreterContext {
   private AngularObjectRegistry angularObjectRegistry;
   private ResourcePool resourcePool;
   private List<InterpreterContextRunner> runners;
+  private String className;
 
   public InterpreterContext(String noteId,
                             String paragraphId,
@@ -124,28 +125,11 @@ public class InterpreterContext {
     return runners;
   }
 
-  public String getRequiredReplName() {
-    if (paragraphText == null) {
-      return null;
-    }
-
-    // get script head
-    int scriptHeadIndex = 0;
-    for (int i = 0; i < paragraphText.length(); i++) {
-      char ch = paragraphText.charAt(i);
-      if (Character.isWhitespace(ch) || ch == '(') {
-        scriptHeadIndex = i;
-        break;
-      }
-    }
-    if (scriptHeadIndex == 0) {
-      return null;
-    }
-    String head = paragraphText.substring(0, scriptHeadIndex);
-    if (head.startsWith("%")) {
-      return head.substring(1);
-    } else {
-      return null;
-    }
+  public String getClassName() {
+    return className;
+  }
+  
+  public void setClassName(String className) {
+    this.className = className;
   }
 }

zeppelin-interpreter/src/main/java/org/apache/zeppelin/interpreter/remote/RemoteInterpreterServer.java

@@ -295,6 +295,7 @@ public class RemoteInterpreterServer
     }
     Interpreter intp = getInterpreter(noteId, className);
     InterpreterContext context = convert(interpreterContext);
+    context.setClassName(intp.getClassName());
 
     Scheduler scheduler = intp.getScheduler();
     InterpretJobListener jobListener = new InterpretJobListener();