From 24f8eac12a981d8edf85d9409cc5e2c626e1585d Mon Sep 17 00:00:00 2001
From: Arjen Poutsma <arjen.poutsma@broadcom.com>
Date: Mon, 18 Dec 2023 15:22:48 +0100
Subject: [PATCH] Improve ByteBuffer copy method

This commit improves JettyWebSocketHandlerAdapter::copyByteBuffer so
that it allocates a buffer large enough for the remaining bytes
contained in the source, instead of allocating one with the capacity of
the source.

Closes gh-31857
---
 .../socket/adapter/jetty/JettyWebSocketHandlerAdapter.java   | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/spring-websocket/src/main/java/org/springframework/web/socket/adapter/jetty/JettyWebSocketHandlerAdapter.java b/spring-websocket/src/main/java/org/springframework/web/socket/adapter/jetty/JettyWebSocketHandlerAdapter.java
index af62342431b..5254abc4725 100644
--- a/spring-websocket/src/main/java/org/springframework/web/socket/adapter/jetty/JettyWebSocketHandlerAdapter.java
+++ b/spring-websocket/src/main/java/org/springframework/web/socket/adapter/jetty/JettyWebSocketHandlerAdapter.java
@@ -118,8 +118,9 @@ public class JettyWebSocketHandlerAdapter {
 	}
 
 	private static ByteBuffer copyByteBuffer(ByteBuffer src) {
-		ByteBuffer dest = ByteBuffer.allocate(src.capacity());
-		dest.put(0, src, 0, src.remaining());
+		ByteBuffer dest = ByteBuffer.allocate(src.remaining());
+		dest.put(src);
+		dest.flip();
 		return dest;
 	}