diff --git a/buffer/src/main/java/io/netty/buffer/CompositeByteBuf.java b/buffer/src/main/java/io/netty/buffer/CompositeByteBuf.java
index 57f59d4c43..ed34fdff63 100644
--- a/buffer/src/main/java/io/netty/buffer/CompositeByteBuf.java
+++ b/buffer/src/main/java/io/netty/buffer/CompositeByteBuf.java
@@ -1319,7 +1319,7 @@ public class CompositeByteBuf extends AbstractReferenceCountedByteBuf {
         return result + ", components=" + components.size() + ')';
     }
 
-    private final class Component {
+    private static final class Component {
         final ByteBuf buf;
         final int length;
         int offset;
diff --git a/codec-http/src/main/java/io/netty/handler/codec/http/HttpResponseDecoder.java b/codec-http/src/main/java/io/netty/handler/codec/http/HttpResponseDecoder.java
index 2d9d90af79..340d6251ab 100644
--- a/codec-http/src/main/java/io/netty/handler/codec/http/HttpResponseDecoder.java
+++ b/codec-http/src/main/java/io/netty/handler/codec/http/HttpResponseDecoder.java
@@ -110,7 +110,7 @@ public class HttpResponseDecoder extends HttpObjectDecoder {
     protected HttpMessage createMessage(String[] initialLine) {
         return new DefaultHttpResponse(
                 HttpVersion.valueOf(initialLine[0]),
-                new HttpResponseStatus(Integer.valueOf(initialLine[1]), initialLine[2]), validateHeaders);
+                new HttpResponseStatus(Integer.parseInt(initialLine[1]), initialLine[2]), validateHeaders);
     }
 
     @Override
diff --git a/codec-http/src/main/java/io/netty/handler/codec/rtsp/RtspResponseDecoder.java b/codec-http/src/main/java/io/netty/handler/codec/rtsp/RtspResponseDecoder.java
index 0137157567..cdf49902a4 100644
--- a/codec-http/src/main/java/io/netty/handler/codec/rtsp/RtspResponseDecoder.java
+++ b/codec-http/src/main/java/io/netty/handler/codec/rtsp/RtspResponseDecoder.java
@@ -78,7 +78,7 @@ public class RtspResponseDecoder extends RtspObjectDecoder {
     protected HttpMessage createMessage(String[] initialLine) throws Exception {
         return new DefaultHttpResponse(
                 RtspVersions.valueOf(initialLine[0]),
-                new HttpResponseStatus(Integer.valueOf(initialLine[1]), initialLine[2]), validateHeaders);
+                new HttpResponseStatus(Integer.parseInt(initialLine[1]), initialLine[2]), validateHeaders);
     }
 
     @Override
diff --git a/common/src/main/java/io/netty/util/internal/NativeLibraryLoader.java b/common/src/main/java/io/netty/util/internal/NativeLibraryLoader.java
index 8a7cee2ef7..91e718ebcc 100644
--- a/common/src/main/java/io/netty/util/internal/NativeLibraryLoader.java
+++ b/common/src/main/java/io/netty/util/internal/NativeLibraryLoader.java
@@ -44,11 +44,7 @@ public final class NativeLibraryLoader {
         String workdir = SystemPropertyUtil.get("io.netty.native.workdir");
         if (workdir != null) {
             File f = new File(workdir);
-            if (!f.exists()) {
-                // ok to ignore as createTempFile will take care
-                //noinspection ResultOfMethodCallIgnored
-                f.mkdirs();
-            }
+            f.mkdirs();
 
             try {
                 f = f.getAbsoluteFile();
@@ -130,9 +126,7 @@ public final class NativeLibraryLoader {
         }
 
         File f = new File(path);
-        if (!f.exists()) {
-            f.mkdirs();
-        }
+        f.mkdirs();
 
         if (!f.isDirectory()) {
             return null;
diff --git a/common/src/main/java/io/netty/util/internal/PlatformDependent.java b/common/src/main/java/io/netty/util/internal/PlatformDependent.java
index 812c75f5e1..2d261c83d5 100644
--- a/common/src/main/java/io/netty/util/internal/PlatformDependent.java
+++ b/common/src/main/java/io/netty/util/internal/PlatformDependent.java
@@ -759,9 +759,7 @@ public final class PlatformDependent {
         }
 
         File f = new File(path);
-        if (!f.exists()) {
-            f.mkdirs();
-        }
+        f.mkdirs();
 
         if (!f.isDirectory()) {
             return null;