From d5e897bba2635aff601cb526884164db80a9dd61 Mon Sep 17 00:00:00 2001
From: Trustin Lee <t@motd.kr>
Date: Fri, 14 Feb 2014 13:03:52 -0800
Subject: [PATCH] Determine the default allocator from system property

- Add ByteBufAllocator.DEFAULT
- The default allocator is now 'pooled'
---
 .../io/netty/buffer/ByteBufAllocator.java     |  2 ++
 .../java/io/netty/buffer/ByteBufUtil.java     | 23 +++++++++++++++++++
 .../netty/channel/DefaultChannelConfig.java   |  4 +---
 3 files changed, 26 insertions(+), 3 deletions(-)

diff --git a/buffer/src/main/java/io/netty/buffer/ByteBufAllocator.java b/buffer/src/main/java/io/netty/buffer/ByteBufAllocator.java
index 9ced16c185..e1778020b2 100644
--- a/buffer/src/main/java/io/netty/buffer/ByteBufAllocator.java
+++ b/buffer/src/main/java/io/netty/buffer/ByteBufAllocator.java
@@ -21,6 +21,8 @@ package io.netty.buffer;
  */
 public interface ByteBufAllocator {
 
+    ByteBufAllocator DEFAULT = ByteBufUtil.DEFAULT_ALLOCATOR;
+
     /**
      * Allocate a {@link ByteBuf}. If it is a direct or heap buffer
      * depends on the actual implementation.
diff --git a/buffer/src/main/java/io/netty/buffer/ByteBufUtil.java b/buffer/src/main/java/io/netty/buffer/ByteBufUtil.java
index f501ed13ca..23f3bd5182 100644
--- a/buffer/src/main/java/io/netty/buffer/ByteBufUtil.java
+++ b/buffer/src/main/java/io/netty/buffer/ByteBufUtil.java
@@ -16,6 +16,9 @@
 package io.netty.buffer;
 
 import io.netty.util.CharsetUtil;
+import io.netty.util.internal.SystemPropertyUtil;
+import io.netty.util.internal.logging.InternalLogger;
+import io.netty.util.internal.logging.InternalLoggerFactory;
 
 import java.nio.ByteBuffer;
 import java.nio.ByteOrder;
@@ -25,20 +28,40 @@ import java.nio.charset.Charset;
 import java.nio.charset.CharsetDecoder;
 import java.nio.charset.CharsetEncoder;
 import java.nio.charset.CoderResult;
+import java.util.Locale;
 
 /**
  * A collection of utility methods that is related with handling {@link ByteBuf}.
  */
 public final class ByteBufUtil {
 
+    private static final InternalLogger logger = InternalLoggerFactory.getInstance(ByteBufUtil.class);
+
     private static final char[] HEXDUMP_TABLE = new char[256 * 4];
 
+    static final ByteBufAllocator DEFAULT_ALLOCATOR;
+
     static {
         final char[] DIGITS = "0123456789abcdef".toCharArray();
         for (int i = 0; i < 256; i ++) {
             HEXDUMP_TABLE[ i << 1     ] = DIGITS[i >>> 4 & 0x0F];
             HEXDUMP_TABLE[(i << 1) + 1] = DIGITS[i       & 0x0F];
         }
+
+        String allocType = SystemPropertyUtil.get("io.netty.allocator.type", "pooled").toLowerCase(Locale.US).trim();
+        ByteBufAllocator alloc;
+        if ("unpooled".equals(allocType)) {
+            alloc = UnpooledByteBufAllocator.DEFAULT;
+            logger.debug("-Dio.netty.allocator.type: {}", allocType);
+        } else if ("pooled".equals(allocType)) {
+            alloc = PooledByteBufAllocator.DEFAULT;
+            logger.debug("-Dio.netty.allocator.type: {}", allocType);
+        } else {
+            alloc = PooledByteBufAllocator.DEFAULT;
+            logger.debug("-Dio.netty.allocator.type: pooled (unknown: {})", allocType);
+        }
+
+        DEFAULT_ALLOCATOR = alloc;
     }
 
     /**
diff --git a/transport/src/main/java/io/netty/channel/DefaultChannelConfig.java b/transport/src/main/java/io/netty/channel/DefaultChannelConfig.java
index 7404a8f8d9..a69620dd1f 100644
--- a/transport/src/main/java/io/netty/channel/DefaultChannelConfig.java
+++ b/transport/src/main/java/io/netty/channel/DefaultChannelConfig.java
@@ -16,7 +16,6 @@
 package io.netty.channel;
 
 import io.netty.buffer.ByteBufAllocator;
-import io.netty.buffer.UnpooledByteBufAllocator;
 import io.netty.channel.nio.AbstractNioByteChannel;
 import io.netty.channel.socket.SocketChannelConfig;
 
@@ -31,7 +30,6 @@ import static io.netty.channel.ChannelOption.*;
  */
 public class DefaultChannelConfig implements ChannelConfig {
 
-    private static final ByteBufAllocator DEFAULT_ALLOCATOR = UnpooledByteBufAllocator.DEFAULT;
     private static final RecvByteBufAllocator DEFAULT_RCVBUF_ALLOCATOR = AdaptiveRecvByteBufAllocator.DEFAULT;
     private static final MessageSizeEstimator DEFAULT_MSG_SIZE_ESTIMATOR = DefaultMessageSizeEstimator.DEFAULT;
 
@@ -39,7 +37,7 @@ public class DefaultChannelConfig implements ChannelConfig {
 
     protected final Channel channel;
 
-    private volatile ByteBufAllocator allocator = DEFAULT_ALLOCATOR;
+    private volatile ByteBufAllocator allocator = ByteBufAllocator.DEFAULT;
     private volatile RecvByteBufAllocator rcvBufAllocator = DEFAULT_RCVBUF_ALLOCATOR;
     private volatile MessageSizeEstimator msgSizeEstimator = DEFAULT_MSG_SIZE_ESTIMATOR;