diff --git a/modules/core/src/main/java/org/apache/ignite/internal/processors/cache/distributed/dht/GridDhtTxOnePhaseCommitAckRequest.java b/modules/core/src/main/java/org/apache/ignite/internal/processors/cache/distributed/dht/GridDhtTxOnePhaseCommitAckRequest.java
index 50f2e7947b1c4..e2ab60bfb21e2 100644
--- a/modules/core/src/main/java/org/apache/ignite/internal/processors/cache/distributed/dht/GridDhtTxOnePhaseCommitAckRequest.java
+++ b/modules/core/src/main/java/org/apache/ignite/internal/processors/cache/distributed/dht/GridDhtTxOnePhaseCommitAckRequest.java
@@ -96,13 +96,11 @@ public Collection<GridCacheVersion> versions() {
             writer.onHeaderWritten();
         }
 
-        switch (writer.state()) {
-            case 3:
-                if (!writer.writeCollection("vers", vers, MessageCollectionItemType.MSG))
-                    return false;
-
-                writer.incrementState();
+        if (writer.state() == 3) {
+            if (!writer.writeCollection("vers", vers, MessageCollectionItemType.MSG))
+                return false;
 
+            writer.incrementState();
         }
 
         return true;
@@ -118,15 +116,13 @@ public Collection<GridCacheVersion> versions() {
         if (!super.readFrom(buf, reader))
             return false;
 
-        switch (reader.state()) {
-            case 3:
-                vers = reader.readCollection("vers", MessageCollectionItemType.MSG);
+        if (reader.state() == 3) {
+            vers = reader.readCollection("vers", MessageCollectionItemType.MSG);
 
-                if (!reader.isLastRead())
-                    return false;
-
-                reader.incrementState();
+            if (!reader.isLastRead())
+                return false;
 
+            reader.incrementState();
         }
 
         return reader.afterMessageRead(GridDhtTxOnePhaseCommitAckRequest.class);
diff --git a/modules/core/src/main/java/org/apache/ignite/internal/processors/cache/distributed/near/GridNearGetRequest.java b/modules/core/src/main/java/org/apache/ignite/internal/processors/cache/distributed/near/GridNearGetRequest.java
index 2fa955abbdddc..4f8d6282e89a8 100644
--- a/modules/core/src/main/java/org/apache/ignite/internal/processors/cache/distributed/near/GridNearGetRequest.java
+++ b/modules/core/src/main/java/org/apache/ignite/internal/processors/cache/distributed/near/GridNearGetRequest.java
@@ -288,14 +288,14 @@ public long accessTtl() {
      * @param ctx Cache context.
      * @throws IgniteCheckedException If failed.
      */
-    @Override public void prepareMarshal(GridCacheSharedContext ctx) throws IgniteCheckedException {
+    @Override public void prepareMarshal(GridCacheSharedContext<?, ?> ctx) throws IgniteCheckedException {
         super.prepareMarshal(ctx);
 
         assert ctx != null;
         assert !F.isEmpty(keys);
         assert readersFlags == null || keys.size() == readersFlags.size();
 
-        GridCacheContext cctx = ctx.cacheContext(cacheId);
+        GridCacheContext<?, ?> cctx = ctx.cacheContext(cacheId);
 
         prepareMarshalCacheObjects(keys, cctx);
     }
@@ -305,10 +305,10 @@ public long accessTtl() {
      * @param ldr Loader.
      * @throws IgniteCheckedException If failed.
      */
-    @Override public void finishUnmarshal(GridCacheSharedContext ctx, ClassLoader ldr) throws IgniteCheckedException {
+    @Override public void finishUnmarshal(GridCacheSharedContext<?, ?> ctx, ClassLoader ldr) throws IgniteCheckedException {
         super.finishUnmarshal(ctx, ldr);
 
-        GridCacheContext cctx = ctx.cacheContext(cacheId);
+        GridCacheContext<?, ?> cctx = ctx.cacheContext(cacheId);
 
         finishUnmarshalCacheObjects(keys, cctx, ldr);
 
diff --git a/modules/core/src/main/java/org/apache/ignite/internal/processors/cache/distributed/near/GridNearGetResponse.java b/modules/core/src/main/java/org/apache/ignite/internal/processors/cache/distributed/near/GridNearGetResponse.java
index 50e3dcdef4ee3..96acb7f5ff6c6 100644
--- a/modules/core/src/main/java/org/apache/ignite/internal/processors/cache/distributed/near/GridNearGetResponse.java
+++ b/modules/core/src/main/java/org/apache/ignite/internal/processors/cache/distributed/near/GridNearGetResponse.java
@@ -131,7 +131,7 @@ public IgniteUuid miniId() {
      * @return Entries.
      */
     public Collection<GridCacheEntryInfo> entries() {
-        return entries != null ? entries : Collections.<GridCacheEntryInfo>emptyList();
+        return entries != null ? entries : Collections.emptyList();
     }
 
     /**
@@ -178,10 +178,10 @@ public void error(IgniteCheckedException err) {
 
     /** {@inheritDoc}
      * @param ctx*/
-    @Override public void prepareMarshal(GridCacheSharedContext ctx) throws IgniteCheckedException {
+    @Override public void prepareMarshal(GridCacheSharedContext<?, ?> ctx) throws IgniteCheckedException {
         super.prepareMarshal(ctx);
 
-        GridCacheContext cctx = ctx.cacheContext(cacheId);
+        GridCacheContext<?, ?> cctx = ctx.cacheContext(cacheId);
 
         if (entries != null) {
             for (GridCacheEntryInfo info : entries)
@@ -193,10 +193,10 @@ public void error(IgniteCheckedException err) {
     }
 
     /** {@inheritDoc} */
-    @Override public void finishUnmarshal(GridCacheSharedContext ctx, ClassLoader ldr) throws IgniteCheckedException {
+    @Override public void finishUnmarshal(GridCacheSharedContext<?, ?> ctx, ClassLoader ldr) throws IgniteCheckedException {
         super.finishUnmarshal(ctx, ldr);
 
-        GridCacheContext cctx = ctx.cacheContext(cacheId());
+        GridCacheContext<?, ?> cctx = ctx.cacheContext(cacheId());
 
         if (entries != null) {
             for (GridCacheEntryInfo info : entries)
diff --git a/modules/core/src/main/java/org/apache/ignite/internal/processors/cache/transactions/TxLockList.java b/modules/core/src/main/java/org/apache/ignite/internal/processors/cache/transactions/TxLockList.java
index 566f341281a33..94e212370c923 100644
--- a/modules/core/src/main/java/org/apache/ignite/internal/processors/cache/transactions/TxLockList.java
+++ b/modules/core/src/main/java/org/apache/ignite/internal/processors/cache/transactions/TxLockList.java
@@ -84,13 +84,11 @@ public boolean isEmpty() {
             writer.onHeaderWritten();
         }
 
-        switch (writer.state()) {
-            case 0:
-                if (!writer.writeCollection("txLocks", txLocks, MessageCollectionItemType.MSG))
-                    return false;
-
-                writer.incrementState();
+        if (writer.state() == 0) {
+            if (!writer.writeCollection("txLocks", txLocks, MessageCollectionItemType.MSG))
+                return false;
 
+            writer.incrementState();
         }
 
         return true;
@@ -103,15 +101,13 @@ public boolean isEmpty() {
         if (!reader.beforeMessageRead())
             return false;
 
-        switch (reader.state()) {
-            case 0:
-                txLocks = reader.readCollection("txLocks", MessageCollectionItemType.MSG);
+        if (reader.state() == 0) {
+            txLocks = reader.readCollection("txLocks", MessageCollectionItemType.MSG);
 
-                if (!reader.isLastRead())
-                    return false;
-
-                reader.incrementState();
+            if (!reader.isLastRead())
+                return false;
 
+            reader.incrementState();
         }
 
         return reader.afterMessageRead(TxLockList.class);
diff --git a/modules/core/src/main/java/org/apache/ignite/internal/processors/cache/transactions/TxLocksRequest.java b/modules/core/src/main/java/org/apache/ignite/internal/processors/cache/transactions/TxLocksRequest.java
index 86109c8f323a9..36bca5d8e9cf7 100644
--- a/modules/core/src/main/java/org/apache/ignite/internal/processors/cache/transactions/TxLocksRequest.java
+++ b/modules/core/src/main/java/org/apache/ignite/internal/processors/cache/transactions/TxLocksRequest.java
@@ -105,7 +105,7 @@ public Collection<IgniteTxKey> txKeys() {
     }
 
     /** {@inheritDoc} */
-    @Override public void prepareMarshal(GridCacheSharedContext ctx) throws IgniteCheckedException {
+    @Override public void prepareMarshal(GridCacheSharedContext<?, ?> ctx) throws IgniteCheckedException {
         super.prepareMarshal(ctx);
 
         txKeysArr = new IgniteTxKey[txKeys.size()];
@@ -120,7 +120,7 @@ public Collection<IgniteTxKey> txKeys() {
     }
 
     /** {@inheritDoc} */
-    @Override public void finishUnmarshal(GridCacheSharedContext ctx, ClassLoader ldr) throws IgniteCheckedException {
+    @Override public void finishUnmarshal(GridCacheSharedContext<?, ?> ctx, ClassLoader ldr) throws IgniteCheckedException {
         super.finishUnmarshal(ctx, ldr);
 
         txKeys = U.newHashSet(txKeysArr.length);
@@ -207,9 +207,4 @@ public Collection<IgniteTxKey> txKeys() {
     @Override public byte fieldsCount() {
         return 5;
     }
-
-    /** {@inheritDoc} */
-    @Override public void onAckReceived() {
-        // No-op.
-    }
 }
diff --git a/modules/core/src/main/java/org/apache/ignite/internal/processors/cache/transactions/TxLocksResponse.java b/modules/core/src/main/java/org/apache/ignite/internal/processors/cache/transactions/TxLocksResponse.java
index df5caa978b609..cdf913c7bd5b1 100644
--- a/modules/core/src/main/java/org/apache/ignite/internal/processors/cache/transactions/TxLocksResponse.java
+++ b/modules/core/src/main/java/org/apache/ignite/internal/processors/cache/transactions/TxLocksResponse.java
@@ -47,7 +47,7 @@ public class TxLocksResponse extends GridCacheMessage {
     /** Locks for near txKeys of near transactions. */
     @GridToStringInclude
     @GridDirectTransient
-    private Map<IgniteTxKey, TxLockList> nearTxKeyLocks = new HashMap<>();
+    private final Map<IgniteTxKey, TxLockList> nearTxKeyLocks = new HashMap<>();
 
     /** Remote keys involved into transactions. Doesn't include near keys. */
     @GridToStringInclude
@@ -153,7 +153,7 @@ public void addKey(IgniteTxKey key) {
     }
 
     /** {@inheritDoc} */
-    @Override public void prepareMarshal(GridCacheSharedContext ctx) throws IgniteCheckedException {
+    @Override public void prepareMarshal(GridCacheSharedContext<?, ?> ctx) throws IgniteCheckedException {
         super.prepareMarshal(ctx);
 
         if (nearTxKeyLocks != null && !nearTxKeyLocks.isEmpty()) {
@@ -190,7 +190,7 @@ public void addKey(IgniteTxKey key) {
     }
 
     /** {@inheritDoc} */
-    @Override public void finishUnmarshal(GridCacheSharedContext ctx, ClassLoader ldr) throws IgniteCheckedException {
+    @Override public void finishUnmarshal(GridCacheSharedContext<?, ?> ctx, ClassLoader ldr) throws IgniteCheckedException {
         try {
             super.finishUnmarshal(ctx, ldr);
 
@@ -325,9 +325,4 @@ public void addKey(IgniteTxKey key) {
     @Override public byte fieldsCount() {
         return 7;
     }
-
-    /** {@inheritDoc} */
-    @Override public void onAckReceived() {
-        // No-op.
-    }
 }