diff --git a/spring-web/src/main/java/org/springframework/web/util/ContentCachingResponseWrapper.java b/spring-web/src/main/java/org/springframework/web/util/ContentCachingResponseWrapper.java
index 4223a67397..1487809d94 100644
--- a/spring-web/src/main/java/org/springframework/web/util/ContentCachingResponseWrapper.java
+++ b/spring-web/src/main/java/org/springframework/web/util/ContentCachingResponseWrapper.java
@@ -38,11 +38,12 @@ import org.springframework.util.FastByteArrayOutputStream;
 /**
  * {@link jakarta.servlet.http.HttpServletResponse} wrapper that caches all content written to
  * the {@linkplain #getOutputStream() output stream} and {@linkplain #getWriter() writer},
- * and allows this content to be retrieved via a {@link #getContentAsByteArray() byte array}.
+ * and allows this content to be retrieved via a {@linkplain #getContentAsByteArray() byte array}.
  *
  * <p>Used e.g. by {@link org.springframework.web.filter.ShallowEtagHeaderFilter}.
  *
  * @author Juergen Hoeller
+ * @author Sam Brannen
  * @since 4.1.3
  * @see ContentCachingRequestWrapper
  */
@@ -120,9 +121,16 @@ public class ContentCachingResponseWrapper extends HttpServletResponseWrapper {
 		return this.writer;
 	}
 
+	/**
+	 * This method neither flushes content to the client nor commits the underlying
+	 * response, since the content has not yet been copied to the response.
+	 * <p>Invoke {@link #copyBodyToResponse()} to copy the cached body content to
+	 * the wrapped response object and flush its buffer.
+	 * @see jakarta.servlet.ServletResponseWrapper#flushBuffer()
+	 */
 	@Override
 	public void flushBuffer() throws IOException {
-		// do not flush the underlying response as the content has not been copied to it yet
+		// no-op
 	}
 
 	@Override
@@ -139,31 +147,30 @@ public class ContentCachingResponseWrapper extends HttpServletResponseWrapper {
 			throw new IllegalArgumentException("Content-Length exceeds ContentCachingResponseWrapper's maximum (" +
 					Integer.MAX_VALUE + "): " + len);
 		}
-		int lenInt = (int) len;
-		if (lenInt > this.content.size()) {
-			this.content.resize(lenInt);
-		}
-		this.contentLength = lenInt;
+		setContentLength((int) len);
 	}
 
 	@Override
-	public void setContentType(String type) {
+	public void setContentType(@Nullable String type) {
 		this.contentType = type;
 	}
 
 	@Override
 	@Nullable
 	public String getContentType() {
-		return this.contentType;
+		if (this.contentType != null) {
+			return this.contentType;
+		}
+		return super.getContentType();
 	}
 
 	@Override
 	public boolean containsHeader(String name) {
-		if (HttpHeaders.CONTENT_LENGTH.equalsIgnoreCase(name)) {
-			return this.contentLength != null;
+		if (this.contentLength != null && HttpHeaders.CONTENT_LENGTH.equalsIgnoreCase(name)) {
+			return true;
 		}
-		else if (HttpHeaders.CONTENT_TYPE.equalsIgnoreCase(name)) {
-			return this.contentType != null;
+		else if (this.contentType != null && HttpHeaders.CONTENT_TYPE.equalsIgnoreCase(name)) {
+			return true;
 		}
 		else {
 			return super.containsHeader(name);
@@ -219,10 +226,10 @@ public class ContentCachingResponseWrapper extends HttpServletResponseWrapper {
 	@Override
 	@Nullable
 	public String getHeader(String name) {
-		if (HttpHeaders.CONTENT_LENGTH.equalsIgnoreCase(name)) {
-			return (this.contentLength != null) ? this.contentLength.toString() : null;
+		if (this.contentLength != null && HttpHeaders.CONTENT_LENGTH.equalsIgnoreCase(name)) {
+			return this.contentLength.toString();
 		}
-		else if (HttpHeaders.CONTENT_TYPE.equalsIgnoreCase(name)) {
+		else if (this.contentType != null && HttpHeaders.CONTENT_TYPE.equalsIgnoreCase(name)) {
 			return this.contentType;
 		}
 		else {
@@ -232,12 +239,11 @@ public class ContentCachingResponseWrapper extends HttpServletResponseWrapper {
 
 	@Override
 	public Collection<String> getHeaders(String name) {
-		if (HttpHeaders.CONTENT_LENGTH.equalsIgnoreCase(name)) {
-			return this.contentLength != null ? Collections.singleton(this.contentLength.toString()) :
-					Collections.emptySet();
+		if (this.contentLength != null && HttpHeaders.CONTENT_LENGTH.equalsIgnoreCase(name)) {
+			return Collections.singleton(this.contentLength.toString());
 		}
-		else if (HttpHeaders.CONTENT_TYPE.equalsIgnoreCase(name)) {
-			return this.contentType != null ? Collections.singleton(this.contentType) : Collections.emptySet();
+		else if (this.contentType != null && HttpHeaders.CONTENT_TYPE.equalsIgnoreCase(name)) {
+			return Collections.singleton(this.contentType);
 		}
 		else {
 			return super.getHeaders(name);
@@ -327,7 +333,7 @@ public class ContentCachingResponseWrapper extends HttpServletResponseWrapper {
 					}
 					this.contentLength = null;
 				}
-				if (complete || this.contentType != null) {
+				if (this.contentType != null) {
 					rawResponse.setContentType(this.contentType);
 					this.contentType = null;
 				}
diff --git a/spring-web/src/test/java/org/springframework/web/filter/ContentCachingResponseWrapperTests.java b/spring-web/src/test/java/org/springframework/web/filter/ContentCachingResponseWrapperTests.java
index 691386f998..e63f206f95 100644
--- a/spring-web/src/test/java/org/springframework/web/filter/ContentCachingResponseWrapperTests.java
+++ b/spring-web/src/test/java/org/springframework/web/filter/ContentCachingResponseWrapperTests.java
@@ -16,28 +16,31 @@
 
 package org.springframework.web.filter;
 
-import java.nio.charset.StandardCharsets;
-
 import jakarta.servlet.http.HttpServletResponse;
 import org.junit.jupiter.api.Test;
 
-import org.springframework.http.HttpHeaders;
+import org.springframework.http.MediaType;
 import org.springframework.util.FileCopyUtils;
 import org.springframework.web.testfixture.servlet.MockHttpServletResponse;
 import org.springframework.web.util.ContentCachingResponseWrapper;
 
+import static java.nio.charset.StandardCharsets.UTF_8;
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.springframework.http.HttpHeaders.CONTENT_LENGTH;
+import static org.springframework.http.HttpHeaders.CONTENT_TYPE;
+import static org.springframework.http.HttpHeaders.TRANSFER_ENCODING;
 
 /**
  * Tests for {@link ContentCachingResponseWrapper}.
  *
  * @author Rossen Stoyanchev
+ * @author Sam Brannen
  */
 class ContentCachingResponseWrapperTests {
 
 	@Test
 	void copyBodyToResponse() throws Exception {
-		byte[] responseBody = "Hello World".getBytes(StandardCharsets.UTF_8);
+		byte[] responseBody = "Hello World".getBytes(UTF_8);
 		MockHttpServletResponse response = new MockHttpServletResponse();
 
 		ContentCachingResponseWrapper responseWrapper = new ContentCachingResponseWrapper(response);
@@ -45,25 +48,98 @@ class ContentCachingResponseWrapperTests {
 		FileCopyUtils.copy(responseBody, responseWrapper.getOutputStream());
 		responseWrapper.copyBodyToResponse();
 
-		assertThat(response.getStatus()).isEqualTo(200);
+		assertThat(response.getStatus()).isEqualTo(HttpServletResponse.SC_OK);
 		assertThat(response.getContentLength()).isGreaterThan(0);
 		assertThat(response.getContentAsByteArray()).isEqualTo(responseBody);
 	}
 
+	@Test
+	void copyBodyToResponseWithPresetHeaders() throws Exception {
+		String PUZZLE = "puzzle";
+		String ENIGMA = "enigma";
+		String NUMBER = "number";
+		String MAGIC = "42";
+
+		byte[] responseBody = "Hello World".getBytes(UTF_8);
+		String responseLength = Integer.toString(responseBody.length);
+		String contentType = MediaType.APPLICATION_JSON_VALUE;
+
+		MockHttpServletResponse response = new MockHttpServletResponse();
+		response.setContentType(contentType);
+		response.setContentLength(999);
+		response.setHeader(PUZZLE, ENIGMA);
+		response.setIntHeader(NUMBER, 42);
+
+		ContentCachingResponseWrapper responseWrapper = new ContentCachingResponseWrapper(response);
+		responseWrapper.setStatus(HttpServletResponse.SC_OK);
+
+		assertThat(responseWrapper.getStatus()).isEqualTo(HttpServletResponse.SC_OK);
+		assertThat(responseWrapper.getContentSize()).isZero();
+		assertThat(responseWrapper.getHeaderNames())
+				.containsExactlyInAnyOrder(PUZZLE, NUMBER, CONTENT_TYPE, CONTENT_LENGTH);
+
+		assertThat(responseWrapper.containsHeader(PUZZLE)).as(PUZZLE).isTrue();
+		assertThat(responseWrapper.getHeader(PUZZLE)).as(PUZZLE).isEqualTo(ENIGMA);
+		assertThat(responseWrapper.getHeaders(PUZZLE)).as(PUZZLE).containsExactly(ENIGMA);
+
+		assertThat(responseWrapper.containsHeader(NUMBER)).as(NUMBER).isTrue();
+		assertThat(responseWrapper.getHeader(NUMBER)).as(NUMBER).isEqualTo(MAGIC);
+		assertThat(responseWrapper.getHeaders(NUMBER)).as(NUMBER).containsExactly(MAGIC);
+
+		assertThat(responseWrapper.containsHeader(CONTENT_TYPE)).as(CONTENT_TYPE).isTrue();
+		assertThat(responseWrapper.getHeader(CONTENT_TYPE)).as(CONTENT_TYPE).isEqualTo(contentType);
+		assertThat(responseWrapper.getHeaders(CONTENT_TYPE)).as(CONTENT_TYPE).containsExactly(contentType);
+		assertThat(responseWrapper.getContentType()).as(CONTENT_TYPE).isEqualTo(contentType);
+
+		assertThat(responseWrapper.containsHeader(CONTENT_LENGTH)).as(CONTENT_LENGTH).isTrue();
+		assertThat(responseWrapper.getHeader(CONTENT_LENGTH)).as(CONTENT_LENGTH).isEqualTo("999");
+		assertThat(responseWrapper.getHeaders(CONTENT_LENGTH)).as(CONTENT_LENGTH).containsExactly("999");
+
+		FileCopyUtils.copy(responseBody, responseWrapper.getOutputStream());
+		responseWrapper.copyBodyToResponse();
+
+		assertThat(responseWrapper.getHeaderNames())
+				.containsExactlyInAnyOrder(PUZZLE, NUMBER, CONTENT_TYPE, CONTENT_LENGTH);
+
+		assertThat(response.getStatus()).isEqualTo(HttpServletResponse.SC_OK);
+		assertThat(response.getContentType()).isEqualTo(contentType);
+		assertThat(response.getContentLength()).isEqualTo(responseBody.length);
+		assertThat(response.getContentAsByteArray()).isEqualTo(responseBody);
+		assertThat(response.getHeaderNames())
+				.containsExactlyInAnyOrder(PUZZLE, NUMBER, CONTENT_TYPE, CONTENT_LENGTH);
+
+		assertThat(response.containsHeader(PUZZLE)).as(PUZZLE).isTrue();
+		assertThat(response.getHeader(PUZZLE)).as(PUZZLE).isEqualTo(ENIGMA);
+		assertThat(response.getHeaders(PUZZLE)).as(PUZZLE).containsExactly(ENIGMA);
+
+		assertThat(response.containsHeader(NUMBER)).as(NUMBER).isTrue();
+		assertThat(response.getHeader(NUMBER)).as(NUMBER).isEqualTo(MAGIC);
+		assertThat(response.getHeaders(NUMBER)).as(NUMBER).containsExactly(MAGIC);
+
+		assertThat(response.containsHeader(CONTENT_TYPE)).as(CONTENT_TYPE).isTrue();
+		assertThat(response.getHeader(CONTENT_TYPE)).as(CONTENT_TYPE).isEqualTo(contentType);
+		assertThat(response.getHeaders(CONTENT_TYPE)).as(CONTENT_TYPE).containsExactly(contentType);
+		assertThat(response.getContentType()).as(CONTENT_TYPE).isEqualTo(contentType);
+
+		assertThat(response.containsHeader(CONTENT_LENGTH)).as(CONTENT_LENGTH).isTrue();
+		assertThat(response.getHeader(CONTENT_LENGTH)).as(CONTENT_LENGTH).isEqualTo(responseLength);
+		assertThat(response.getHeaders(CONTENT_LENGTH)).as(CONTENT_LENGTH).containsExactly(responseLength);
+	}
+
 	@Test
 	void copyBodyToResponseWithTransferEncoding() throws Exception {
-		byte[] responseBody = "6\r\nHello 5\r\nWorld0\r\n\r\n".getBytes(StandardCharsets.UTF_8);
+		byte[] responseBody = "6\r\nHello 5\r\nWorld0\r\n\r\n".getBytes(UTF_8);
 		MockHttpServletResponse response = new MockHttpServletResponse();
 
 		ContentCachingResponseWrapper responseWrapper = new ContentCachingResponseWrapper(response);
 		responseWrapper.setStatus(HttpServletResponse.SC_OK);
-		responseWrapper.setHeader(HttpHeaders.TRANSFER_ENCODING, "chunked");
+		responseWrapper.setHeader(TRANSFER_ENCODING, "chunked");
 		FileCopyUtils.copy(responseBody, responseWrapper.getOutputStream());
 		responseWrapper.copyBodyToResponse();
 
-		assertThat(response.getStatus()).isEqualTo(200);
-		assertThat(response.getHeader(HttpHeaders.TRANSFER_ENCODING)).isEqualTo("chunked");
-		assertThat(response.getHeader(HttpHeaders.CONTENT_LENGTH)).isNull();
+		assertThat(response.getStatus()).isEqualTo(HttpServletResponse.SC_OK);
+		assertThat(response.getHeader(TRANSFER_ENCODING)).isEqualTo("chunked");
+		assertThat(response.getHeader(CONTENT_LENGTH)).isNull();
 		assertThat(response.getContentAsByteArray()).isEqualTo(responseBody);
 	}