diff --git a/java/com/android/dialer/simulator/Simulator.java b/java/com/android/dialer/simulator/Simulator.java
index 2094b42..d75d10e 100644
--- a/java/com/android/dialer/simulator/Simulator.java
+++ b/java/com/android/dialer/simulator/Simulator.java
@@ -42,6 +42,19 @@
   static final int CONFERENCE_TYPE_GSM = 1;
   static final int CONFERENCE_TYPE_VOLTE = 2;
 
+  /** The types of connection service listener events */
+  @Retention(RetentionPolicy.SOURCE)
+  @IntDef({
+    ON_NEW_OUTGOING_CONNECTION,
+    ON_NEW_INCOMING_CONNECTION,
+    ON_CONFERENCE,
+  })
+  @interface ConnectionServiceEventType {}
+
+  static final int ON_NEW_OUTGOING_CONNECTION = 1;
+  static final int ON_NEW_INCOMING_CONNECTION = 2;
+  static final int ON_CONFERENCE = 3;
+
   /** Information about a connection event. */
   public static class Event {
     /** The type of connection event. */
diff --git a/java/com/android/dialer/simulator/SimulatorComponent.java b/java/com/android/dialer/simulator/SimulatorComponent.java
index f14496b..dee1882 100644
--- a/java/com/android/dialer/simulator/SimulatorComponent.java
+++ b/java/com/android/dialer/simulator/SimulatorComponent.java
@@ -26,6 +26,8 @@
 
   public abstract Simulator getSimulator();
 
+  public abstract SimulatorConnectionsBank getSimulatorConnectionsBank();
+
   public static SimulatorComponent get(Context context) {
     return ((HasComponent) ((HasRootComponent) context.getApplicationContext()).component())
         .simulatorComponent();
diff --git a/java/com/android/dialer/simulator/SimulatorConnectionsBank.java b/java/com/android/dialer/simulator/SimulatorConnectionsBank.java
new file mode 100644
index 0000000..23c0042
--- /dev/null
+++ b/java/com/android/dialer/simulator/SimulatorConnectionsBank.java
@@ -0,0 +1,55 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License
+ */
+
+package com.android.dialer.simulator;
+
+import android.content.Context;
+import android.support.annotation.NonNull;
+import android.telecom.Connection;
+import com.android.dialer.simulator.Simulator.ConferenceType;
+import java.util.List;
+
+/**
+ * Used to create a shared connections bank which contains methods to manipulate connections. This
+ * is used mainly for conference calling.
+ */
+public interface SimulatorConnectionsBank {
+
+  /** Add a connection into bank. */
+  void add(Connection connection);
+
+  /** Remove a connection from bank. */
+  void remove(Connection connection);
+
+  /** Merge all existing connections created by simulator into a conference. */
+  void mergeAllConnections(@ConferenceType int conferenceType, Context context);
+
+  /** Set all connections created by simulator to disconnected. */
+  void disconnectAllConnections();
+
+  /**
+   * Update conferenceable connections for all connections in bank (usually after adding a new
+   * connection). Before calling this method, make sure all connections are returned by
+   * ConnectionService.
+   */
+  void updateConferenceableConnections();
+
+  /** Determine whether a connection is created by simulator. */
+  boolean isSimulatorConnection(@NonNull Connection connection);
+
+  /** Get all connections tags from bank. */
+  List<String> getConnectionTags();
+}
diff --git a/java/com/android/dialer/simulator/impl/SimulatorConferenceCreator.java b/java/com/android/dialer/simulator/impl/SimulatorConferenceCreator.java
index d024993..36c1995 100644
--- a/java/com/android/dialer/simulator/impl/SimulatorConferenceCreator.java
+++ b/java/com/android/dialer/simulator/impl/SimulatorConferenceCreator.java
@@ -19,8 +19,6 @@
 import android.content.Context;
 import android.os.Bundle;
 import android.support.annotation.NonNull;
-import android.support.annotation.Nullable;
-import android.telecom.Conferenceable;
 import android.telecom.Connection;
 import android.telecom.DisconnectCause;
 import com.android.dialer.common.Assert;
@@ -28,8 +26,9 @@
 import com.android.dialer.common.concurrent.ThreadUtil;
 import com.android.dialer.simulator.Simulator;
 import com.android.dialer.simulator.Simulator.Event;
+import com.android.dialer.simulator.SimulatorComponent;
+import com.android.dialer.simulator.SimulatorConnectionsBank;
 import java.util.ArrayList;
-import java.util.List;
 import java.util.Locale;
 
 /** Creates a conference with a given number of participants. */
@@ -38,32 +37,59 @@
         SimulatorConnection.Listener,
         SimulatorConference.Listener {
   private static final String EXTRA_CALL_COUNT = "call_count";
-
+  private static final String RECONNECT = "reconnect";
   @NonNull private final Context context;
-  @NonNull private final List<String> connectionTags = new ArrayList<>();
+
+  private final SimulatorConnectionsBank simulatorConnectionsBank;
+
+  private boolean onNewIncomingConnectionEnabled = false;
+
   @Simulator.ConferenceType private final int conferenceType;
 
   public SimulatorConferenceCreator(
       @NonNull Context context, @Simulator.ConferenceType int conferenceType) {
     this.context = Assert.isNotNull(context);
     this.conferenceType = conferenceType;
+    simulatorConnectionsBank = SimulatorComponent.get(context).getSimulatorConnectionsBank();
   }
 
   void start(int callCount) {
+    onNewIncomingConnectionEnabled = true;
     SimulatorConnectionService.addListener(this);
-    addNextCall(callCount);
+    if (conferenceType == Simulator.CONFERENCE_TYPE_VOLTE) {
+      addNextCall(callCount, true);
+    } else if (conferenceType == Simulator.CONFERENCE_TYPE_GSM) {
+      addNextCall(callCount, false);
+    }
   }
-
-  private void addNextCall(int callCount) {
+  /**
+   * Add a call in a process of making a conference.
+   *
+   * @param callCount the remaining number of calls to make
+   * @param reconnect whether all connections should reconnect once (connections are reconnected
+   *     once in making VoLTE conference)
+   */
+  private void addNextCall(int callCount, boolean reconnect) {
     LogUtil.i("SimulatorConferenceCreator.addNextIncomingCall", "callCount: " + callCount);
     if (callCount <= 0) {
       LogUtil.i("SimulatorConferenceCreator.addNextCall", "done adding calls");
+      if (reconnect) {
+        simulatorConnectionsBank.disconnectAllConnections();
+        addNextCall(simulatorConnectionsBank.getConnectionTags().size(), false);
+      } else {
+        simulatorConnectionsBank.mergeAllConnections(conferenceType, context);
+        SimulatorConnectionService.removeListener(this);
+      }
       return;
     }
-
     String callerId = String.format(Locale.US, "+1-650-234%04d", callCount);
     Bundle extras = new Bundle();
     extras.putInt(EXTRA_CALL_COUNT, callCount - 1);
+    extras.putBoolean(RECONNECT, reconnect);
+    addConferenceCall(callerId, extras);
+  }
+
+  private void addConferenceCall(String number, Bundle extras) {
     switch (conferenceType) {
       case Simulator.CONFERENCE_TYPE_VOLTE:
         extras.putBoolean("ISVOLTE", true);
@@ -71,35 +97,25 @@
       default:
         break;
     }
-    connectionTags.add(
-        SimulatorSimCallManager.addNewIncomingCall(context, callerId, false /* isVideo */, extras));
+    SimulatorSimCallManager.addNewIncomingCall(context, number, false /* isVideo */, extras);
   }
 
   @Override
   public void onNewIncomingConnection(@NonNull SimulatorConnection connection) {
-    if (!isMyConnection(connection)) {
+    if (!onNewIncomingConnectionEnabled) {
+      return;
+    }
+    if (!simulatorConnectionsBank.isSimulatorConnection(connection)) {
       LogUtil.i("SimulatorConferenceCreator.onNewOutgoingConnection", "unknown connection");
       return;
     }
-
     LogUtil.i("SimulatorConferenceCreator.onNewOutgoingConnection", "connection created");
     connection.addListener(this);
-
     // Once the connection is active, go ahead and conference it and add the next call.
     ThreadUtil.postDelayedOnUiThread(
         () -> {
-          SimulatorConference conference = findCurrentConference();
-          if (conference == null) {
-            conference =
-                SimulatorConference.newGsmConference(
-                    SimulatorSimCallManager.getSystemPhoneAccountHandle(context));
-            conference.addListener(this);
-            SimulatorConnectionService.getInstance().addConference(conference);
-          }
-          updateConferenceableConnections();
           connection.setActive();
-          conference.addConnection(connection);
-          addNextCall(getCallCount(connection));
+          addNextCall(getCallCount(connection), shouldReconnect(connection));
         },
         1000);
   }
@@ -115,7 +131,8 @@
   public void onConference(
       @NonNull SimulatorConnection connection1, @NonNull SimulatorConnection connection2) {
     LogUtil.enterBlock("SimulatorConferenceCreator.onConference");
-    if (!isMyConnection(connection1) || !isMyConnection(connection2)) {
+    if (!simulatorConnectionsBank.isSimulatorConnection(connection1)
+        || !simulatorConnectionsBank.isSimulatorConnection(connection2)) {
       LogUtil.i("SimulatorConferenceCreator.onConference", "unknown connections, ignoring");
       return;
     }
@@ -125,7 +142,6 @@
     } else if (connection2.getConference() != null) {
       connection2.getConference().addConnection(connection1);
     } else {
-      Assert.checkArgument(conferenceType == Simulator.CONFERENCE_TYPE_GSM);
       SimulatorConference conference =
           SimulatorConference.newGsmConference(
               SimulatorSimCallManager.getSystemPhoneAccountHandle(context));
@@ -136,54 +152,14 @@
     }
   }
 
-  private boolean isMyConnection(@NonNull Connection connection) {
-    for (String connectionTag : connectionTags) {
-      if (connection.getExtras().getBoolean(connectionTag)) {
-        return true;
-      }
-    }
-    return false;
-  }
-
-  private void updateConferenceableConnections() {
-    LogUtil.enterBlock("SimulatorConferenceCreator.updateConferenceableConnections");
-    for (String connectionTag : connectionTags) {
-      SimulatorConnection connection = SimulatorSimCallManager.findConnectionByTag(connectionTag);
-      List<Conferenceable> conferenceables = getMyConferenceables();
-      conferenceables.remove(connection);
-      conferenceables.remove(connection.getConference());
-      connection.setConferenceables(conferenceables);
-    }
-  }
-
-  private List<Conferenceable> getMyConferenceables() {
-    List<Conferenceable> conferenceables = new ArrayList<>();
-    for (String connectionTag : connectionTags) {
-      SimulatorConnection connection = SimulatorSimCallManager.findConnectionByTag(connectionTag);
-      conferenceables.add(connection);
-      if (connection.getConference() != null
-          && !conferenceables.contains(connection.getConference())) {
-        conferenceables.add(connection.getConference());
-      }
-    }
-    return conferenceables;
-  }
-
-  @Nullable
-  private SimulatorConference findCurrentConference() {
-    for (String connectionTag : connectionTags) {
-      SimulatorConnection connection = SimulatorSimCallManager.findConnectionByTag(connectionTag);
-      if (connection.getConference() != null) {
-        return (SimulatorConference) connection.getConference();
-      }
-    }
-    return null;
-  }
-
   private static int getCallCount(@NonNull Connection connection) {
     return connection.getExtras().getInt(EXTRA_CALL_COUNT);
   }
 
+  private static boolean shouldReconnect(@NonNull Connection connection) {
+    return connection.getExtras().getBoolean(RECONNECT);
+  }
+
   @Override
   public void onEvent(@NonNull SimulatorConnection connection, @NonNull Event event) {
     switch (event.type) {
@@ -222,6 +198,7 @@
         for (Connection connection : new ArrayList<>(conference.getConnections())) {
           connection.setDisconnected(new DisconnectCause(DisconnectCause.LOCAL));
         }
+        conference.setDisconnected(new DisconnectCause(DisconnectCause.LOCAL));
         break;
       default:
         LogUtil.i(
diff --git a/java/com/android/dialer/simulator/impl/SimulatorConnection.java b/java/com/android/dialer/simulator/impl/SimulatorConnection.java
index 168f5db..2a24d8f 100644
--- a/java/com/android/dialer/simulator/impl/SimulatorConnection.java
+++ b/java/com/android/dialer/simulator/impl/SimulatorConnection.java
@@ -24,6 +24,8 @@
 import com.android.dialer.common.Assert;
 import com.android.dialer.common.LogUtil;
 import com.android.dialer.simulator.Simulator.Event;
+import com.android.dialer.simulator.SimulatorComponent;
+import com.android.dialer.simulator.SimulatorConnectionsBank;
 import java.util.ArrayList;
 import java.util.List;
 
@@ -31,6 +33,7 @@
 public final class SimulatorConnection extends Connection {
   private final List<Listener> listeners = new ArrayList<>();
   private final List<Event> events = new ArrayList<>();
+  private final SimulatorConnectionsBank simulatorConnectionsBank;
   private int currentState = STATE_NEW;
 
   SimulatorConnection(@NonNull Context context, @NonNull ConnectionRequest request) {
@@ -47,6 +50,7 @@
       setConnectionCapabilities(getConnectionCapabilities() | CAPABILITY_SEPARATE_FROM_CONFERENCE);
     }
     setVideoProvider(new SimulatorVideoProvider(context, this));
+    simulatorConnectionsBank = SimulatorComponent.get(context).getSimulatorConnectionsBank();
   }
 
   public void addListener(@NonNull Listener listener) {
@@ -71,6 +75,7 @@
   @Override
   public void onReject() {
     LogUtil.enterBlock("SimulatorConnection.onReject");
+    simulatorConnectionsBank.remove(this);
     onEvent(new Event(Event.REJECT));
   }
 
@@ -89,6 +94,7 @@
   @Override
   public void onDisconnect() {
     LogUtil.enterBlock("SimulatorConnection.onDisconnect");
+    simulatorConnectionsBank.remove(this);
     onEvent(new Event(Event.DISCONNECT));
   }
 
diff --git a/java/com/android/dialer/simulator/impl/SimulatorConnectionService.java b/java/com/android/dialer/simulator/impl/SimulatorConnectionService.java
index 465890c..e6bf99f 100644
--- a/java/com/android/dialer/simulator/impl/SimulatorConnectionService.java
+++ b/java/com/android/dialer/simulator/impl/SimulatorConnectionService.java
@@ -28,6 +28,9 @@
 import android.widget.Toast;
 import com.android.dialer.common.Assert;
 import com.android.dialer.common.LogUtil;
+import com.android.dialer.common.concurrent.ThreadUtil;
+import com.android.dialer.simulator.SimulatorComponent;
+import com.android.dialer.simulator.SimulatorConnectionsBank;
 import java.util.ArrayList;
 import java.util.List;
 
@@ -35,6 +38,7 @@
 public class SimulatorConnectionService extends ConnectionService {
   private static final List<Listener> listeners = new ArrayList<>();
   private static SimulatorConnectionService instance;
+  private SimulatorConnectionsBank simulatorConnectionsBank;
 
   public static SimulatorConnectionService getInstance() {
     return instance;
@@ -52,12 +56,14 @@
   public void onCreate() {
     super.onCreate();
     instance = this;
+    simulatorConnectionsBank = SimulatorComponent.get(this).getSimulatorConnectionsBank();
   }
 
   @Override
   public void onDestroy() {
     LogUtil.enterBlock("SimulatorConnectionService.onDestroy");
     instance = null;
+    simulatorConnectionsBank = null;
     super.onDestroy();
   }
 
@@ -78,7 +84,12 @@
     SimulatorConnection connection = new SimulatorConnection(this, request);
     connection.setDialing();
     connection.setAddress(request.getAddress(), TelecomManager.PRESENTATION_ALLOWED);
-
+    simulatorConnectionsBank.add(connection);
+    ThreadUtil.postOnUiThread(
+        () ->
+            SimulatorComponent.get(instance)
+                .getSimulatorConnectionsBank()
+                .updateConferenceableConnections());
     for (Listener listener : listeners) {
       listener.onNewOutgoingConnection(connection);
     }
@@ -102,7 +113,12 @@
     SimulatorConnection connection = new SimulatorConnection(this, request);
     connection.setRinging();
     connection.setAddress(getPhoneNumber(request), TelecomManager.PRESENTATION_ALLOWED);
-
+    simulatorConnectionsBank.add(connection);
+    ThreadUtil.postOnUiThread(
+        () ->
+            SimulatorComponent.get(instance)
+                .getSimulatorConnectionsBank()
+                .updateConferenceableConnections());
     for (Listener listener : listeners) {
       listener.onNewIncomingConnection(connection);
     }
diff --git a/java/com/android/dialer/simulator/impl/SimulatorConnectionsBankImpl.java b/java/com/android/dialer/simulator/impl/SimulatorConnectionsBankImpl.java
new file mode 100644
index 0000000..75f144f
--- /dev/null
+++ b/java/com/android/dialer/simulator/impl/SimulatorConnectionsBankImpl.java
@@ -0,0 +1,147 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License
+ */
+
+package com.android.dialer.simulator.impl;
+
+import android.content.Context;
+import android.support.annotation.NonNull;
+import android.telecom.Conferenceable;
+import android.telecom.Connection;
+import android.telecom.DisconnectCause;
+import com.android.dialer.common.LogUtil;
+import com.android.dialer.simulator.Simulator;
+import com.android.dialer.simulator.Simulator.ConferenceType;
+import com.android.dialer.simulator.Simulator.Event;
+import com.android.dialer.simulator.SimulatorConnectionsBank;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.List;
+import javax.inject.Inject;
+
+/** Wraps a list of connection tags and common methods around the connection tags list. */
+public class SimulatorConnectionsBankImpl
+    implements SimulatorConnectionsBank, SimulatorConference.Listener {
+  private final List<String> connectionTags = new ArrayList<>();
+
+  @Inject
+  public SimulatorConnectionsBankImpl() {}
+
+  @Override
+  public List<String> getConnectionTags() {
+    return connectionTags;
+  }
+
+  @Override
+  public void add(Connection connection) {
+    connectionTags.add(SimulatorSimCallManager.getConnectionTag(connection));
+  }
+
+  @Override
+  public void remove(Connection connection) {
+    connectionTags.remove(SimulatorSimCallManager.getConnectionTag(connection));
+  }
+
+  @Override
+  public void mergeAllConnections(@ConferenceType int conferenceType, Context context) {
+    SimulatorConference simulatorConference = null;
+    if (conferenceType == Simulator.CONFERENCE_TYPE_GSM) {
+      simulatorConference =
+          SimulatorConference.newGsmConference(
+              SimulatorSimCallManager.getSystemPhoneAccountHandle(context));
+    } else if (conferenceType == Simulator.CONFERENCE_TYPE_VOLTE) {
+      simulatorConference =
+          SimulatorConference.newVoLteConference(
+              SimulatorSimCallManager.getSystemPhoneAccountHandle(context));
+    }
+    Collection<Connection> connections =
+        SimulatorConnectionService.getInstance().getAllConnections();
+    for (Connection connection : connections) {
+      simulatorConference.addConnection(connection);
+    }
+    simulatorConference.addListener(this);
+    SimulatorConnectionService.getInstance().addConference(simulatorConference);
+  }
+
+  @Override
+  public void disconnectAllConnections() {
+    Collection<Connection> connections =
+        SimulatorConnectionService.getInstance().getAllConnections();
+    for (Connection connection : connections) {
+      connection.setDisconnected(new DisconnectCause(DisconnectCause.LOCAL));
+    }
+  }
+
+  @Override
+  public void updateConferenceableConnections() {
+    LogUtil.enterBlock("SimulatorConferenceCreator.updateConferenceableConnections");
+    for (String connectionTag : connectionTags) {
+      SimulatorConnection connection = SimulatorSimCallManager.findConnectionByTag(connectionTag);
+      List<Conferenceable> conferenceables = getSimulatorConferenceables();
+      conferenceables.remove(connection);
+      conferenceables.remove(connection.getConference());
+      connection.setConferenceables(conferenceables);
+    }
+  }
+
+  private List<Conferenceable> getSimulatorConferenceables() {
+    List<Conferenceable> conferenceables = new ArrayList<>();
+    for (String connectionTag : connectionTags) {
+      SimulatorConnection connection = SimulatorSimCallManager.findConnectionByTag(connectionTag);
+      conferenceables.add(connection);
+      if (connection.getConference() != null
+          && !conferenceables.contains(connection.getConference())) {
+        conferenceables.add(connection.getConference());
+      }
+    }
+    return conferenceables;
+  }
+
+  @Override
+  public boolean isSimulatorConnection(@NonNull Connection connection) {
+    for (String connectionTag : connectionTags) {
+      if (connection.getExtras().getBoolean(connectionTag)) {
+        return true;
+      }
+    }
+    return false;
+  }
+
+  @Override
+  public void onEvent(@NonNull SimulatorConference conference, @NonNull Event event) {
+    switch (event.type) {
+      case Event.MERGE:
+        int capabilities = conference.getConnectionCapabilities();
+        capabilities |= Connection.CAPABILITY_SWAP_CONFERENCE;
+        conference.setConnectionCapabilities(capabilities);
+        break;
+      case Event.SEPARATE:
+        SimulatorConnection connectionToRemove =
+            SimulatorSimCallManager.findConnectionByTag(event.data1);
+        conference.removeConnection(connectionToRemove);
+        break;
+      case Event.DISCONNECT:
+        for (Connection connection : new ArrayList<>(conference.getConnections())) {
+          connection.setDisconnected(new DisconnectCause(DisconnectCause.LOCAL));
+        }
+        conference.setDisconnected(new DisconnectCause(DisconnectCause.LOCAL));
+        break;
+      default:
+        LogUtil.i(
+            "SimulatorConferenceCreator.onEvent", "unexpected conference event: " + event.type);
+        break;
+    }
+  }
+}
diff --git a/java/com/android/dialer/simulator/impl/SimulatorModule.java b/java/com/android/dialer/simulator/impl/SimulatorModule.java
index c0cca27..2bc72c9 100644
--- a/java/com/android/dialer/simulator/impl/SimulatorModule.java
+++ b/java/com/android/dialer/simulator/impl/SimulatorModule.java
@@ -17,6 +17,7 @@
 package com.android.dialer.simulator.impl;
 
 import com.android.dialer.simulator.Simulator;
+import com.android.dialer.simulator.SimulatorConnectionsBank;
 import dagger.Binds;
 import dagger.Module;
 import javax.inject.Singleton;
@@ -27,4 +28,9 @@
   @Binds
   @Singleton
   public abstract Simulator bindsSimulator(SimulatorImpl simulator);
+
+  @Binds
+  @Singleton
+  public abstract SimulatorConnectionsBank bindsSimulatorConnectionsBank(
+      SimulatorConnectionsBankImpl simulatorConnectionsBank);
 }
diff --git a/java/com/android/dialer/simulator/impl/SimulatorVoiceCall.java b/java/com/android/dialer/simulator/impl/SimulatorVoiceCall.java
index d2eba6b..451896b 100644
--- a/java/com/android/dialer/simulator/impl/SimulatorVoiceCall.java
+++ b/java/com/android/dialer/simulator/impl/SimulatorVoiceCall.java
@@ -52,6 +52,8 @@
   private SimulatorVoiceCall(@NonNull Context context) {
     this.context = Assert.isNotNull(context);
     SimulatorConnectionService.addListener(this);
+    SimulatorConnectionService.addListener(
+        new SimulatorConferenceCreator(context, Simulator.CONFERENCE_TYPE_GSM));
   }
 
   private void addNewIncomingCall(boolean isSpam) {