diff --git a/asterix-bad/src/main/java/org/apache/asterix/bad/lang/statement/BrokerDropStatement.java b/asterix-bad/src/main/java/org/apache/asterix/bad/lang/statement/BrokerDropStatement.java
index 90beef7..485a1e1 100644
--- a/asterix-bad/src/main/java/org/apache/asterix/bad/lang/statement/BrokerDropStatement.java
+++ b/asterix-bad/src/main/java/org/apache/asterix/bad/lang/statement/BrokerDropStatement.java
@@ -18,7 +18,7 @@
  */
 package org.apache.asterix.bad.lang.statement;
 
-import org.apache.asterix.algebra.extension.IExtensionStatement;
+import org.apache.asterix.algebra.extension.ExtensionStatement;
 import org.apache.asterix.app.translator.QueryTranslator;
 import org.apache.asterix.bad.lang.BADLangExtension;
 import org.apache.asterix.bad.metadata.Broker;
@@ -34,7 +34,7 @@
 import org.apache.hyracks.api.client.IHyracksClientConnection;
 import org.apache.hyracks.api.exceptions.HyracksDataException;
 
-public class BrokerDropStatement implements IExtensionStatement {
+public class BrokerDropStatement extends ExtensionStatement {
 
     private final Identifier dataverseName;
     private final Identifier brokerName;
@@ -59,11 +59,6 @@
     }
 
     @Override
-    public byte getKind() {
-        return Kind.EXTENSION;
-    }
-
-    @Override
     public byte getCategory() {
         return Category.DDL;
     }
diff --git a/asterix-bad/src/main/java/org/apache/asterix/bad/lang/statement/ChannelDropStatement.java b/asterix-bad/src/main/java/org/apache/asterix/bad/lang/statement/ChannelDropStatement.java
index e4b6d89..3d43ee6 100644
--- a/asterix-bad/src/main/java/org/apache/asterix/bad/lang/statement/ChannelDropStatement.java
+++ b/asterix-bad/src/main/java/org/apache/asterix/bad/lang/statement/ChannelDropStatement.java
@@ -23,7 +23,7 @@
 import java.util.logging.Logger;
 
 import org.apache.asterix.active.EntityId;
-import org.apache.asterix.algebra.extension.IExtensionStatement;
+import org.apache.asterix.algebra.extension.ExtensionStatement;
 import org.apache.asterix.app.active.ActiveNotificationHandler;
 import org.apache.asterix.app.translator.QueryTranslator;
 import org.apache.asterix.bad.BADConstants;
@@ -45,7 +45,7 @@
 import org.apache.hyracks.api.exceptions.HyracksDataException;
 import org.apache.hyracks.api.job.DeployedJobSpecId;
 
-public class ChannelDropStatement implements IExtensionStatement {
+public class ChannelDropStatement extends ExtensionStatement {
     private static final Logger LOGGER = Logger.getLogger(ChannelDropStatement.class.getName());
 
     private final Identifier dataverseName;
@@ -71,11 +71,6 @@
     }
 
     @Override
-    public byte getKind() {
-        return Kind.EXTENSION;
-    }
-
-    @Override
     public byte getCategory() {
         return Category.DDL;
     }
diff --git a/asterix-bad/src/main/java/org/apache/asterix/bad/lang/statement/ChannelSubscribeStatement.java b/asterix-bad/src/main/java/org/apache/asterix/bad/lang/statement/ChannelSubscribeStatement.java
index bab6ad2..5f08845 100644
--- a/asterix-bad/src/main/java/org/apache/asterix/bad/lang/statement/ChannelSubscribeStatement.java
+++ b/asterix-bad/src/main/java/org/apache/asterix/bad/lang/statement/ChannelSubscribeStatement.java
@@ -21,7 +21,7 @@
 import java.util.ArrayList;
 import java.util.List;
 
-import org.apache.asterix.algebra.extension.IExtensionStatement;
+import org.apache.asterix.algebra.extension.ExtensionStatement;
 import org.apache.asterix.app.translator.QueryTranslator;
 import org.apache.asterix.bad.BADConstants;
 import org.apache.asterix.bad.lang.BADLangExtension;
@@ -59,7 +59,7 @@
 import org.apache.hyracks.api.dataset.ResultSetId;
 import org.apache.hyracks.api.exceptions.HyracksDataException;
 
-public class ChannelSubscribeStatement implements IExtensionStatement {
+public class ChannelSubscribeStatement extends ExtensionStatement {
 
     private final Identifier dataverseName;
     private final Identifier channelName;
@@ -109,11 +109,6 @@
     }
 
     @Override
-    public byte getKind() {
-        return Kind.EXTENSION;
-    }
-
-    @Override
     public byte getCategory() {
         return Category.QUERY;
     }
diff --git a/asterix-bad/src/main/java/org/apache/asterix/bad/lang/statement/ChannelUnsubscribeStatement.java b/asterix-bad/src/main/java/org/apache/asterix/bad/lang/statement/ChannelUnsubscribeStatement.java
index e456768..79c8efd 100644
--- a/asterix-bad/src/main/java/org/apache/asterix/bad/lang/statement/ChannelUnsubscribeStatement.java
+++ b/asterix-bad/src/main/java/org/apache/asterix/bad/lang/statement/ChannelUnsubscribeStatement.java
@@ -21,7 +21,7 @@
 import java.util.ArrayList;
 import java.util.List;
 
-import org.apache.asterix.algebra.extension.IExtensionStatement;
+import org.apache.asterix.algebra.extension.ExtensionStatement;
 import org.apache.asterix.app.translator.QueryTranslator;
 import org.apache.asterix.bad.BADConstants;
 import org.apache.asterix.bad.lang.BADLangExtension;
@@ -51,7 +51,7 @@
 import org.apache.hyracks.api.client.IHyracksClientConnection;
 import org.apache.hyracks.api.exceptions.HyracksDataException;
 
-public class ChannelUnsubscribeStatement implements IExtensionStatement {
+public class ChannelUnsubscribeStatement extends ExtensionStatement {
 
     private final Identifier dataverseName;
     private final Identifier channelName;
@@ -89,11 +89,6 @@
     }
 
     @Override
-    public byte getKind() {
-        return Kind.EXTENSION;
-    }
-
-    @Override
     public byte getCategory() {
         return Category.UPDATE;
     }
diff --git a/asterix-bad/src/main/java/org/apache/asterix/bad/lang/statement/CreateBrokerStatement.java b/asterix-bad/src/main/java/org/apache/asterix/bad/lang/statement/CreateBrokerStatement.java
index 6369854..99aded8 100644
--- a/asterix-bad/src/main/java/org/apache/asterix/bad/lang/statement/CreateBrokerStatement.java
+++ b/asterix-bad/src/main/java/org/apache/asterix/bad/lang/statement/CreateBrokerStatement.java
@@ -21,7 +21,7 @@
 import java.util.logging.Level;
 import java.util.logging.Logger;
 
-import org.apache.asterix.algebra.extension.IExtensionStatement;
+import org.apache.asterix.algebra.extension.ExtensionStatement;
 import org.apache.asterix.app.translator.QueryTranslator;
 import org.apache.asterix.bad.lang.BADLangExtension;
 import org.apache.asterix.bad.metadata.Broker;
@@ -37,7 +37,7 @@
 import org.apache.hyracks.api.client.IHyracksClientConnection;
 import org.apache.hyracks.api.exceptions.HyracksDataException;
 
-public class CreateBrokerStatement implements IExtensionStatement {
+public class CreateBrokerStatement extends ExtensionStatement {
 
     private static final Logger LOGGER = Logger.getLogger(CreateBrokerStatement.class.getName());
     private final Identifier dataverseName;
@@ -63,11 +63,6 @@
     }
 
     @Override
-    public byte getKind() {
-        return Kind.EXTENSION;
-    }
-
-    @Override
     public byte getCategory() {
         return Category.DDL;
     }
diff --git a/asterix-bad/src/main/java/org/apache/asterix/bad/lang/statement/CreateChannelStatement.java b/asterix-bad/src/main/java/org/apache/asterix/bad/lang/statement/CreateChannelStatement.java
index 53baf6d..c3c9a1e 100644
--- a/asterix-bad/src/main/java/org/apache/asterix/bad/lang/statement/CreateChannelStatement.java
+++ b/asterix-bad/src/main/java/org/apache/asterix/bad/lang/statement/CreateChannelStatement.java
@@ -30,7 +30,7 @@
 
 import org.apache.asterix.active.DeployedJobService;
 import org.apache.asterix.active.EntityId;
-import org.apache.asterix.algebra.extension.IExtensionStatement;
+import org.apache.asterix.algebra.extension.ExtensionStatement;
 import org.apache.asterix.app.active.ActiveNotificationHandler;
 import org.apache.asterix.app.translator.QueryTranslator;
 import org.apache.asterix.bad.BADConstants;
@@ -80,7 +80,7 @@
 import org.apache.hyracks.api.job.JobSpecification;
 import org.apache.hyracks.dataflow.common.data.parsers.IValueParser;
 
-public class CreateChannelStatement implements IExtensionStatement {
+public class CreateChannelStatement extends ExtensionStatement {
 
     private static final Logger LOGGER = Logger.getLogger(CreateChannelStatement.class.getName());
     private final Identifier channelName;
@@ -162,11 +162,6 @@
         durationParser.parse(duration.toCharArray(), 0, duration.toCharArray().length, outputStream);
     }
 
-    @Override
-    public byte getKind() {
-        return Kind.EXTENSION;
-    }
-
     private void createDatasets(IStatementExecutor statementExecutor, MetadataProvider metadataProvider,
             IHyracksClientConnection hcc) throws AsterixException, Exception {
 
diff --git a/asterix-bad/src/main/java/org/apache/asterix/bad/lang/statement/CreateProcedureStatement.java b/asterix-bad/src/main/java/org/apache/asterix/bad/lang/statement/CreateProcedureStatement.java
index 0908edb..cab66c2 100644
--- a/asterix-bad/src/main/java/org/apache/asterix/bad/lang/statement/CreateProcedureStatement.java
+++ b/asterix-bad/src/main/java/org/apache/asterix/bad/lang/statement/CreateProcedureStatement.java
@@ -27,7 +27,7 @@
 import java.util.logging.Logger;
 
 import org.apache.asterix.active.EntityId;
-import org.apache.asterix.algebra.extension.IExtensionStatement;
+import org.apache.asterix.algebra.extension.ExtensionStatement;
 import org.apache.asterix.app.active.ActiveNotificationHandler;
 import org.apache.asterix.app.translator.QueryTranslator;
 import org.apache.asterix.bad.BADConstants;
@@ -78,7 +78,7 @@
 import org.apache.hyracks.api.job.JobSpecification;
 import org.apache.hyracks.dataflow.common.data.parsers.IValueParser;
 
-public class CreateProcedureStatement implements IExtensionStatement {
+public class CreateProcedureStatement extends ExtensionStatement {
 
     private static final Logger LOGGER = Logger.getLogger(CreateProcedureStatement.class.getName());
 
@@ -116,11 +116,6 @@
         return procedureBodyStatement;
     }
 
-    @Override
-    public byte getKind() {
-        return Kind.EXTENSION;
-    }
-
     public List<String> getParamList() {
         return paramList;
     }
diff --git a/asterix-bad/src/main/java/org/apache/asterix/bad/lang/statement/ExecuteProcedureStatement.java b/asterix-bad/src/main/java/org/apache/asterix/bad/lang/statement/ExecuteProcedureStatement.java
index 7db935a..b597f98 100644
--- a/asterix-bad/src/main/java/org/apache/asterix/bad/lang/statement/ExecuteProcedureStatement.java
+++ b/asterix-bad/src/main/java/org/apache/asterix/bad/lang/statement/ExecuteProcedureStatement.java
@@ -26,7 +26,7 @@
 
 import org.apache.asterix.active.DeployedJobService;
 import org.apache.asterix.active.EntityId;
-import org.apache.asterix.algebra.extension.IExtensionStatement;
+import org.apache.asterix.algebra.extension.ExtensionStatement;
 import org.apache.asterix.api.http.server.ResultUtil;
 import org.apache.asterix.app.active.ActiveNotificationHandler;
 import org.apache.asterix.app.result.ResultReader;
@@ -62,7 +62,7 @@
 import org.apache.hyracks.api.job.JobId;
 import org.apache.hyracks.data.std.util.ArrayBackedValueStorage;
 
-public class ExecuteProcedureStatement implements IExtensionStatement {
+public class ExecuteProcedureStatement extends ExtensionStatement {
 
     public static final String WAIT_FOR_COMPLETION = "wait-for-completion-procedure";
 
@@ -91,11 +91,6 @@
     }
 
     @Override
-    public byte getKind() {
-        return Kind.EXTENSION;
-    }
-
-    @Override
     public byte getCategory() {
         return Category.UPDATE;
     }
diff --git a/asterix-bad/src/main/java/org/apache/asterix/bad/lang/statement/ProcedureDropStatement.java b/asterix-bad/src/main/java/org/apache/asterix/bad/lang/statement/ProcedureDropStatement.java
index f0eaced..ebde605 100644
--- a/asterix-bad/src/main/java/org/apache/asterix/bad/lang/statement/ProcedureDropStatement.java
+++ b/asterix-bad/src/main/java/org/apache/asterix/bad/lang/statement/ProcedureDropStatement.java
@@ -23,7 +23,7 @@
 import java.util.logging.Logger;
 
 import org.apache.asterix.active.EntityId;
-import org.apache.asterix.algebra.extension.IExtensionStatement;
+import org.apache.asterix.algebra.extension.ExtensionStatement;
 import org.apache.asterix.app.active.ActiveNotificationHandler;
 import org.apache.asterix.app.translator.QueryTranslator;
 import org.apache.asterix.bad.BADConstants;
@@ -45,7 +45,7 @@
 import org.apache.hyracks.api.exceptions.HyracksDataException;
 import org.apache.hyracks.api.job.DeployedJobSpecId;
 
-public class ProcedureDropStatement implements IExtensionStatement {
+public class ProcedureDropStatement extends ExtensionStatement {
     private static final Logger LOGGER = Logger.getLogger(ProcedureDropStatement.class.getName());
 
     private final FunctionSignature signature;
@@ -65,11 +65,6 @@
     }
 
     @Override
-    public byte getKind() {
-        return Kind.EXTENSION;
-    }
-
-    @Override
     public byte getCategory() {
         return Category.DDL;
     }