From 4d0800f3924fa8a7fc4a9b411974760b9e4e1305 Mon Sep 17 00:00:00 2001
From: zilong6 <zilong6@staff.weibo.com>
Date: Mon, 9 Jul 2018 19:15:21 +0200
Subject: [PATCH] Improve ContentCachingRequestWrapper performance

This commit improves the performance of `read` method variants
to write to the cache in an optimized way.

Issue: SPR-15762
---
 .../util/ContentCachingRequestWrapper.java    | 51 +++++++++++++++++++
 1 file changed, 51 insertions(+)

diff --git a/spring-web/src/main/java/org/springframework/web/util/ContentCachingRequestWrapper.java b/spring-web/src/main/java/org/springframework/web/util/ContentCachingRequestWrapper.java
index 8fcacc4fac..fc8ec32f32 100644
--- a/spring-web/src/main/java/org/springframework/web/util/ContentCachingRequestWrapper.java
+++ b/spring-web/src/main/java/org/springframework/web/util/ContentCachingRequestWrapper.java
@@ -213,6 +213,57 @@ public class ContentCachingRequestWrapper extends HttpServletRequestWrapper {
 			this.is = is;
 		}
 
+		@Override
+		public int readLine(final byte[] b, final int off, final int len) throws IOException {
+			int count = is.readLine(b, off, len);
+			cache(b, off, count);
+			return count;
+		}
+
+		private void cache(final byte[] b, final int off, final int count) {
+			if (contentCacheLimit != null && cachedContent.size() == contentCacheLimit) {
+				this.overflow = true;
+				handleContentOverflow(contentCacheLimit);
+			} else {
+				int sizeToCache = contentCacheLimit == null || count + cachedContent.size() < contentCacheLimit
+						? count
+						: contentCacheLimit - cachedContent.size();
+				cachedContent.write(b, off, sizeToCache);
+				if (sizeToCache < count) {
+					this.overflow = true;
+					handleContentOverflow(contentCacheLimit);
+				}
+			}
+		}
+
+		@Override
+		public int read(final byte[] b) throws IOException {
+			int count = super.read(b);
+			if (!this.overflow && count > 0) {
+				if (contentCacheLimit != null && cachedContent.size() == contentCacheLimit) {
+					this.overflow = true;
+					handleContentOverflow(contentCacheLimit);
+				} else {
+                    int sizeToCache = contentCacheLimit == null || count + cachedContent.size() < contentCacheLimit
+                            ? count
+                            : contentCacheLimit - cachedContent.size();
+                    cachedContent.write(b, 0, sizeToCache);
+                    if (sizeToCache < count) {
+                    	this.overflow = true;
+                    	handleContentOverflow(contentCacheLimit);
+					}
+				}
+			}
+			return count;
+		}
+
+		@Override
+		public int read(final byte[] b, final int off, final int len) throws IOException {
+			int count = is.read(b, off, len);
+			cache(b, off, count);
+			return count;
+		}
+
 		@Override
 		public int read() throws IOException {
 			int ch = this.is.read();