Possible leak in AbstractDiskHttpData

Motivation:
SonarQube (clinker.netty.io/sonar) reported a resource which may not have been properly closed in all situations in AbstractDiskHttpData.

Modifications:
- Ensure file channels are closed in the presence of exceptions.
- Correct instances where local channels were created but potentially not closed.

Result:
Less leaks. Less SonarQube vulnerabilities.

codec-http/src/main/java/io/netty/handler/codec/http/multipart/AbstractDiskHttpData.java

@@ -120,6 +120,7 @@ public abstract class AbstractDiskHttpData extends AbstractHttpData {
                 return;
             }
             FileOutputStream outputStream = new FileOutputStream(file);
+            try {
                 FileChannel localfileChannel = outputStream.getChannel();
                 ByteBuffer byteBuffer = buffer.nioBuffer();
                 int written = 0;
@@ -128,8 +129,9 @@ public abstract class AbstractDiskHttpData extends AbstractHttpData {
                 }
                 buffer.readerIndex(buffer.readerIndex() + written);
                 localfileChannel.force(false);
-            localfileChannel.close();
+            } finally {
                 outputStream.close();
+            }
             setCompleted();
         } finally {
             // Release the buffer as it was retained before and we not need a reference to it at all
@@ -210,11 +212,12 @@ public abstract class AbstractDiskHttpData extends AbstractHttpData {
         }
         file = tempFile();
         FileOutputStream outputStream = new FileOutputStream(file);
+        int written = 0;
+        try {
             FileChannel localfileChannel = outputStream.getChannel();
             byte[] bytes = new byte[4096 * 4];
             ByteBuffer byteBuffer = ByteBuffer.wrap(bytes);
             int read = inputStream.read(bytes);
-        int written = 0;
             while (read > 0) {
                 byteBuffer.position(read).flip();
                 written += localfileChannel.write(byteBuffer);
@@ -222,7 +225,9 @@ public abstract class AbstractDiskHttpData extends AbstractHttpData {
                 read = inputStream.read(bytes);
             }
             localfileChannel.force(false);
-        localfileChannel.close();
+        } finally {
+            outputStream.close();
+        }
         size = written;
         if (definedSize > 0 && definedSize < size) {
             if (!file.delete()) {
@@ -337,20 +342,51 @@ public abstract class AbstractDiskHttpData extends AbstractHttpData {
         }
         if (!file.renameTo(dest)) {
             // must copy
-            FileInputStream inputStream = new FileInputStream(file);
-            FileOutputStream outputStream = new FileOutputStream(dest);
-            FileChannel in = inputStream.getChannel();
-            FileChannel out = outputStream.getChannel();
+            IOException exception = null;
+            FileInputStream inputStream = null;
+            FileOutputStream outputStream = null;
             long chunkSize = 8196;
             long position = 0;
+            try {
+                inputStream = new FileInputStream(file);
+                outputStream = new FileOutputStream(dest);
+                FileChannel in = inputStream.getChannel();
+                FileChannel out = outputStream.getChannel();
                 while (position < size) {
                     if (chunkSize < size - position) {
                         chunkSize = size - position;
                     }
                     position += in.transferTo(position, chunkSize , out);
                 }
-            in.close();
-            out.close();
+            } catch (IOException e) {
+                exception = e;
+            } finally {
+                if (inputStream != null) {
+                    try {
+                        inputStream.close();
+                    } catch (IOException e) {
+                        if (exception == null) { // Choose to report the first exception
+                            exception = e;
+                        } else {
+                            logger.warn("Multiple exceptions detected, the following will be suppressed {}", e);
+                        }
+                    }
+                }
+                if (outputStream != null) {
+                    try {
+                        outputStream.close();
+                    } catch (IOException e) {
+                        if (exception == null) { // Choose to report the first exception
+                            exception = e;
+                        } else {
+                            logger.warn("Multiple exceptions detected, the following will be suppressed {}", e);
+                        }
+                    }
+                }
+            }
+            if (exception != null) {
+                throw exception;
+            }
             if (position == size) {
                 if (!file.delete()) {
                     logger.warn("Failed to delete: {}", file);
@@ -381,14 +417,17 @@ public abstract class AbstractDiskHttpData extends AbstractHttpData {
                     "File too big to be loaded in memory");
         }
         FileInputStream inputStream = new FileInputStream(src);
-        FileChannel fileChannel = inputStream.getChannel();
         byte[] array = new byte[(int) srcsize];
+        try {
+            FileChannel fileChannel = inputStream.getChannel();
             ByteBuffer byteBuffer = ByteBuffer.wrap(array);
             int read = 0;
             while (read < srcsize) {
                 read += fileChannel.read(byteBuffer);
             }
-        fileChannel.close();
+        } finally {
+            inputStream.close();
+        }
         return array;
     }