diff --git a/src/java.base/linux/classes/sun/nio/ch/EPollSelectorImpl.java b/src/java.base/linux/classes/sun/nio/ch/EPollSelectorImpl.java
index cb55932fd7e..a07a927e635 100644
--- a/src/java.base/linux/classes/sun/nio/ch/EPollSelectorImpl.java
+++ b/src/java.base/linux/classes/sun/nio/ch/EPollSelectorImpl.java
@@ -26,7 +26,6 @@
 package sun.nio.ch;
 
 import java.io.IOException;
-import java.nio.channels.ClosedSelectorException;
 import java.nio.channels.SelectionKey;
 import java.nio.channels.Selector;
 import java.nio.channels.spi.SelectorProvider;
@@ -92,11 +91,6 @@ class EPollSelectorImpl extends SelectorImpl {
         EPoll.ctl(epfd, EPOLL_CTL_ADD, eventfd.efd(), EPOLLIN);
     }
 
-    private void ensureOpen() {
-        if (!isOpen())
-            throw new ClosedSelectorException();
-    }
-
     @Override
     protected int doSelect(Consumer<SelectionKey> action, long timeout)
         throws IOException
@@ -243,7 +237,6 @@ protected void implDereg(SelectionKeyImpl ski) throws IOException {
 
     @Override
     public void setEventOps(SelectionKeyImpl ski) {
-        ensureOpen();
         synchronized (updateLock) {
             updateKeys.addLast(ski);
         }
diff --git a/src/java.base/macosx/classes/sun/nio/ch/KQueueSelectorImpl.java b/src/java.base/macosx/classes/sun/nio/ch/KQueueSelectorImpl.java
index 6c84984f515..6abc9e31879 100644
--- a/src/java.base/macosx/classes/sun/nio/ch/KQueueSelectorImpl.java
+++ b/src/java.base/macosx/classes/sun/nio/ch/KQueueSelectorImpl.java
@@ -26,7 +26,6 @@
 package sun.nio.ch;
 
 import java.io.IOException;
-import java.nio.channels.ClosedSelectorException;
 import java.nio.channels.SelectionKey;
 import java.nio.channels.Selector;
 import java.nio.channels.spi.SelectorProvider;
@@ -97,11 +96,6 @@ class KQueueSelectorImpl extends SelectorImpl {
         KQueue.register(kqfd, fd0, EVFILT_READ, EV_ADD);
     }
 
-    private void ensureOpen() {
-        if (!isOpen())
-            throw new ClosedSelectorException();
-    }
-
     @Override
     protected int doSelect(Consumer<SelectionKey> action, long timeout)
         throws IOException
@@ -285,7 +279,6 @@ protected void implDereg(SelectionKeyImpl ski) throws IOException {
 
     @Override
     public void setEventOps(SelectionKeyImpl ski) {
-        ensureOpen();
         synchronized (updateLock) {
             updateKeys.addLast(ski);
         }
diff --git a/src/java.base/share/classes/java/nio/channels/spi/AbstractSelectableChannel.java b/src/java.base/share/classes/java/nio/channels/spi/AbstractSelectableChannel.java
index 558158cc852..27786d4b874 100644
--- a/src/java.base/share/classes/java/nio/channels/spi/AbstractSelectableChannel.java
+++ b/src/java.base/share/classes/java/nio/channels/spi/AbstractSelectableChannel.java
@@ -137,6 +137,8 @@ private SelectionKey findKey(Selector sel) {
 
     void removeKey(SelectionKey k) {                    // package-private
         synchronized (keyLock) {
+            if (keys == null)
+                return;
             for (int i = 0; i < keys.length; i++)
                 if (keys[i] == k) {
                     keys[i] = null;
@@ -233,7 +235,7 @@ public final SelectionKey register(Selector sel, int ops, Object att)
                     k.interestOps(ops);
                 } else {
                     // New registration
-                    k = ((AbstractSelector)sel).register(this, ops, att);
+                    k = ((AbstractSelector) sel).register(this, ops, att);
                     addKey(k);
                 }
                 return k;
diff --git a/src/java.base/share/classes/sun/nio/ch/SelectorImpl.java b/src/java.base/share/classes/sun/nio/ch/SelectorImpl.java
index bb0d603790f..88f95939d2f 100644
--- a/src/java.base/share/classes/sun/nio/ch/SelectorImpl.java
+++ b/src/java.base/share/classes/sun/nio/ch/SelectorImpl.java
@@ -184,19 +184,16 @@ public final void implCloseSelector() throws IOException {
         wakeup();
         synchronized (this) {
             implClose();
-            synchronized (publicSelectedKeys) {
-                // Deregister channels
-                Iterator<SelectionKey> i = keys.iterator();
-                while (i.hasNext()) {
-                    SelectionKeyImpl ski = (SelectionKeyImpl)i.next();
-                    deregister(ski);
-                    SelectableChannel selch = ski.channel();
-                    if (!selch.isOpen() && !selch.isRegistered())
-                        ((SelChImpl)selch).kill();
-                    selectedKeys.remove(ski);
-                    i.remove();
-                }
-                assert selectedKeys.isEmpty();
+
+            // Deregister channels
+            Iterator<SelectionKey> i = keys.iterator();
+            while (i.hasNext()) {
+                SelectionKeyImpl ski = (SelectionKeyImpl) i.next();
+                deregister(ski);
+                SelectableChannel selch = ski.channel();
+                if (!selch.isOpen() && !selch.isRegistered())
+                    ((SelChImpl) selch).kill();
+                i.remove();
             }
         }
     }
@@ -221,13 +218,13 @@ protected final SelectionKey register(AbstractSelectableChannel ch,
         keys.add(k);
         try {
             k.interestOps(ops);
-        } catch (ClosedSelectorException e) {
-            assert ch.keyFor(this) == null;
+        } catch (CancelledKeyException e) {
+            // key observed and cancelled
+        }
+        if (!isOpen()) {
             keys.remove(k);
             k.cancel();
-            throw e;
-        } catch (CancelledKeyException e) {
-            // key observed and cancelled. Okay to return a cancelled key.
+            throw new ClosedSelectorException();
         }
         return k;
     }
@@ -277,7 +274,7 @@ protected final void processDeregisterQueue() throws IOException {
 
                 SelectableChannel ch = ski.channel();
                 if (!ch.isOpen() && !ch.isRegistered())
-                    ((SelChImpl)ch).kill();
+                    ((SelChImpl) ch).kill();
             }
         }
     }
diff --git a/src/java.base/unix/classes/sun/nio/ch/PollSelectorImpl.java b/src/java.base/unix/classes/sun/nio/ch/PollSelectorImpl.java
index a3bff8d1e65..d29eacb81c1 100644
--- a/src/java.base/unix/classes/sun/nio/ch/PollSelectorImpl.java
+++ b/src/java.base/unix/classes/sun/nio/ch/PollSelectorImpl.java
@@ -231,7 +231,6 @@ protected void implDereg(SelectionKeyImpl ski) throws IOException {
 
     @Override
     public void setEventOps(SelectionKeyImpl ski) {
-        ensureOpen();
         synchronized (updateLock) {
             updateKeys.addLast(ski);
         }
diff --git a/src/java.base/windows/classes/sun/nio/ch/WEPollSelectorImpl.java b/src/java.base/windows/classes/sun/nio/ch/WEPollSelectorImpl.java
index bbcfab9bbf1..f2bff88675f 100644
--- a/src/java.base/windows/classes/sun/nio/ch/WEPollSelectorImpl.java
+++ b/src/java.base/windows/classes/sun/nio/ch/WEPollSelectorImpl.java
@@ -28,7 +28,6 @@
 import java.io.FileDescriptor;
 import java.io.IOException;
 import java.nio.ByteBuffer;
-import java.nio.channels.ClosedSelectorException;
 import java.nio.channels.Pipe;
 import java.nio.channels.SelectionKey;
 import java.nio.channels.Selector;
@@ -89,11 +88,6 @@ class WEPollSelectorImpl extends SelectorImpl {
         WEPoll.ctl(eph, EPOLL_CTL_ADD, fd0Val, WEPoll.EPOLLIN);
     }
 
-    private void ensureOpen() {
-        if (!isOpen())
-            throw new ClosedSelectorException();
-    }
-
     @Override
     protected int doSelect(Consumer<SelectionKey> action, long timeout)
         throws IOException
@@ -228,7 +222,6 @@ protected void implDereg(SelectionKeyImpl ski) throws IOException {
 
     @Override
     public void setEventOps(SelectionKeyImpl ski) {
-        ensureOpen();
         synchronized (updateLock) {
             updateKeys.addLast(ski);
         }
diff --git a/src/java.base/windows/classes/sun/nio/ch/WindowsSelectorImpl.java b/src/java.base/windows/classes/sun/nio/ch/WindowsSelectorImpl.java
index 977a1653fdd..acdb2df326b 100644
--- a/src/java.base/windows/classes/sun/nio/ch/WindowsSelectorImpl.java
+++ b/src/java.base/windows/classes/sun/nio/ch/WindowsSelectorImpl.java
@@ -606,7 +606,6 @@ protected void implDereg(SelectionKeyImpl ski) {
 
     @Override
     public void setEventOps(SelectionKeyImpl ski) {
-        ensureOpen();
         synchronized (updateLock) {
             updateKeys.addLast(ski);
         }