Make classes static wherever possible

codec-http/src/test/java/io/netty/handler/codec/spdy/SpdySessionHandlerTest.java

@@ -273,7 +273,7 @@ public class SpdySessionHandlerTest {
 
     // Echo Handler opens 4 half-closed streams on session connection
     // and then sets the number of concurrent streams to 3
-    private class EchoHandler extends ChannelInboundMessageHandlerAdapter<Object> {
+    private static class EchoHandler extends ChannelInboundMessageHandlerAdapter<Object> {
         private final int closeSignal;
         private final boolean server;
 

common/src/main/java/io/netty/monitor/MonitorRegistries.java

@@ -117,7 +117,7 @@ public final class MonitorRegistries implements Iterable<MonitorRegistry> {
         return new MonitorRegistryIterator(FACTORIES.iterator());
     }
 
-    private final class MonitorRegistryIterator implements Iterator<MonitorRegistry> {
+    private static final class MonitorRegistryIterator implements Iterator<MonitorRegistry> {
 
         private final Iterator<MonitorRegistryFactory> factories;
 

testsuite/src/test/java/io/netty/testsuite/transport/socket/DatagramMulticastTest.java

@@ -95,7 +95,7 @@ public class DatagramMulticastTest extends AbstractDatagramTest {
 
     }
 
-    private final class MulticastTestHandler extends ChannelInboundMessageHandlerAdapter<DatagramPacket> {
+    private static final class MulticastTestHandler extends ChannelInboundMessageHandlerAdapter<DatagramPacket> {
         private final CountDownLatch latch = new CountDownLatch(1);
 
         private boolean done;

testsuite/src/test/java/io/netty/testsuite/transport/socket/ServerSocketSuspendTest.java

@@ -94,7 +94,7 @@ public class ServerSocketSuspendTest extends AbstractServerSocketTest {
     }
 
     @ChannelHandler.Sharable
-    private final class AcceptedChannelCounter extends ChannelInboundByteHandlerAdapter {
+    private static final class AcceptedChannelCounter extends ChannelInboundByteHandlerAdapter {
 
         final CountDownLatch latch;
 

testsuite/src/test/java/io/netty/testsuite/transport/socket/SocketSpdyEchoTest.java

@@ -229,7 +229,7 @@ public class SocketSpdyEchoTest extends AbstractSocketTest {
         }
     }
 
-    private class SpdyEchoTestServerHandler extends ChannelInboundMessageHandlerAdapter<Object> {
+    private static class SpdyEchoTestServerHandler extends ChannelInboundMessageHandlerAdapter<Object> {
         final AtomicReference<Throwable> exception = new AtomicReference<Throwable>();
 
         @Override
@@ -245,7 +245,7 @@ public class SocketSpdyEchoTest extends AbstractSocketTest {
         }
     }
 
-    private class SpdyEchoTestClientHandler extends ChannelInboundByteHandlerAdapter {
+    private static class SpdyEchoTestClientHandler extends ChannelInboundByteHandlerAdapter {
         final AtomicReference<Throwable> exception = new AtomicReference<Throwable>();
         final ByteBuf frames;
         volatile int counter;

transport/src/main/java/com/sun/nio/sctp/AbstractNotificationHandler.java

@@ -15,6 +15,7 @@
  */
 package com.sun.nio.sctp;
 
+@SuppressWarnings("all")
 public class AbstractNotificationHandler<T> implements NotificationHandler<T> {
     static {
         UnsupportedOperatingSystemException.raise();

transport/src/main/java/io/netty/bootstrap/AbstractBootstrap.java

@@ -247,7 +247,7 @@ public abstract class AbstractBootstrap<B extends AbstractBootstrap<?>> {
         return attrs;
     }
 
-    private final class BootstrapChannelFactory implements ChannelFactory {
+    private static final class BootstrapChannelFactory implements ChannelFactory {
         private final Class<? extends Channel> clazz;
 
         BootstrapChannelFactory(Class<? extends Channel> clazz) {

transport/src/test/java/io/netty/channel/local/LocalTransportThreadModelTest2.java

@@ -126,7 +126,7 @@ public class LocalTransportThreadModelTest2 {
     }
 
     @Sharable
-    class LocalHander extends ChannelInboundMessageHandlerAdapter<Object> {
+    static class LocalHander extends ChannelInboundMessageHandlerAdapter<Object> {
         private final String name;
 
         public volatile ChannelFuture lastWriteFuture;