diff --git a/spring-web/src/main/java/org/springframework/http/server/reactive/DefaultServerHttpRequestBuilder.java b/spring-web/src/main/java/org/springframework/http/server/reactive/DefaultServerHttpRequestBuilder.java
index 442ce537604..2bb031b11e4 100644
--- a/spring-web/src/main/java/org/springframework/http/server/reactive/DefaultServerHttpRequestBuilder.java
+++ b/spring-web/src/main/java/org/springframework/http/server/reactive/DefaultServerHttpRequestBuilder.java
@@ -18,6 +18,7 @@ package org.springframework.http.server.reactive;
 
 import java.net.InetSocketAddress;
 import java.net.URI;
+import java.net.URISyntaxException;
 import java.util.LinkedList;
 import java.util.List;
 import java.util.Map;
@@ -33,7 +34,7 @@ import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 import org.springframework.util.LinkedMultiValueMap;
 import org.springframework.util.MultiValueMap;
-import org.springframework.web.util.UriComponentsBuilder;
+import org.springframework.util.StringUtils;
 
 /**
  * Package-private default implementation of {@link ServerHttpRequest.Builder}.
@@ -129,19 +130,49 @@ class DefaultServerHttpRequestBuilder implements ServerHttpRequest.Builder {
 
 	@Override
 	public ServerHttpRequest build() {
-		URI uriToUse = getUriToUse();
-		return new DefaultServerHttpRequest(uriToUse, this.contextPath, this.httpHeaders,
+		return new DefaultServerHttpRequest(getUriToUse(), this.contextPath, this.httpHeaders,
 				this.httpMethodValue, this.cookies, this.body, this.originalRequest);
-
 	}
 
 	private URI getUriToUse() {
 		if (this.uriPath == null) {
 			return this.uri;
 		}
-		return UriComponentsBuilder.fromUri(this.uri).replacePath(this.uriPath).build(true).toUri();
+
+		StringBuilder uriBuilder = new StringBuilder();
+		if (this.uri.getScheme() != null) {
+			uriBuilder.append(this.uri.getScheme()).append(':');
+		}
+		if (this.uri.getUserInfo() != null || this.uri.getHost() != null) {
+			uriBuilder.append("//");
+			if (this.uri.getUserInfo() != null) {
+				uriBuilder.append(this.uri.getUserInfo()).append('@');
+			}
+			if (this.uri.getHost() != null) {
+				uriBuilder.append(this.uri.getHost());
+			}
+			if (this.uri.getPort() != -1) {
+				uriBuilder.append(':').append(this.uri.getPort());
+			}
+		}
+		if (StringUtils.hasLength(this.uriPath)) {
+			uriBuilder.append(this.uriPath);
+		}
+		if (this.uri.getRawQuery() != null) {
+			uriBuilder.append('?').append(this.uri.getRawQuery());
+		}
+		if (this.uri.getFragment() != null) {
+			uriBuilder.append('#').append(this.uri.getFragment());
+		}
+		try {
+			return new URI(uriBuilder.toString());
+		}
+		catch (URISyntaxException ex) {
+			throw new IllegalStateException("Invalid URI path: \"" + this.uriPath + "\"", ex);
+		}
 	}
 
+
 	private static class DefaultServerHttpRequest extends AbstractServerHttpRequest {
 
 		private final String methodValue;
@@ -158,7 +189,6 @@ class DefaultServerHttpRequestBuilder implements ServerHttpRequest.Builder {
 
 		private final ServerHttpRequest originalRequest;
 
-
 		public DefaultServerHttpRequest(URI uri, @Nullable String contextPath,
 				HttpHeaders headers, String methodValue, MultiValueMap<String, HttpCookie> cookies,
 				Flux<DataBuffer> body, ServerHttpRequest originalRequest) {
@@ -172,7 +202,6 @@ class DefaultServerHttpRequestBuilder implements ServerHttpRequest.Builder {
 			this.originalRequest = originalRequest;
 		}
 
-
 		@Override
 		public String getMethodValue() {
 			return this.methodValue;
diff --git a/spring-web/src/main/java/org/springframework/web/util/HierarchicalUriComponents.java b/spring-web/src/main/java/org/springframework/web/util/HierarchicalUriComponents.java
index e96cab4ab0d..e8614657c8b 100644
--- a/spring-web/src/main/java/org/springframework/web/util/HierarchicalUriComponents.java
+++ b/spring-web/src/main/java/org/springframework/web/util/HierarchicalUriComponents.java
@@ -89,7 +89,7 @@ final class HierarchicalUriComponents extends UriComponents {
 
 		super(scheme, fragment);
 
-			this.userInfo = userInfo;
+		this.userInfo = userInfo;
 		this.host = host;
 		this.port = port;
 		this.path = (path != null ? path : NULL_PATH_COMPONENT);
@@ -166,10 +166,8 @@ final class HierarchicalUriComponents extends UriComponents {
 							queryBuilder.append('&');
 						}
 						queryBuilder.append(name);
-
 						if (value != null) {
-							queryBuilder.append('=');
-							queryBuilder.append(value.toString());
+							queryBuilder.append('=').append(value.toString());
 						}
 					}
 				}
@@ -211,8 +209,8 @@ final class HierarchicalUriComponents extends UriComponents {
 		String hostTo = (this.host != null ? encodeUriComponent(this.host, charset, getHostType()) : null);
 		PathComponent pathTo = this.path.encode(charset);
 		MultiValueMap<String, String> paramsTo = encodeQueryParams(charset);
-		return new HierarchicalUriComponents(schemeTo, fragmentTo, userInfoTo, hostTo, this.port,
-				pathTo, paramsTo, true, false);
+		return new HierarchicalUriComponents(
+				schemeTo, fragmentTo, userInfoTo, hostTo, this.port, pathTo, paramsTo, true, false);
 	}
 
 	private MultiValueMap<String, String> encodeQueryParams(Charset charset) {
@@ -355,8 +353,8 @@ final class HierarchicalUriComponents extends UriComponents {
 		PathComponent pathTo = this.path.expand(uriVariables);
 		MultiValueMap<String, String> paramsTo = expandQueryParams(uriVariables);
 
-		return new HierarchicalUriComponents(schemeTo, fragmentTo, userInfoTo, hostTo, portTo,
-				pathTo, paramsTo, false, false);
+		return new HierarchicalUriComponents(
+				schemeTo, fragmentTo, userInfoTo, hostTo, portTo, pathTo, paramsTo, false, false);
 	}
 
 	private MultiValueMap<String, String> expandQueryParams(UriTemplateVariables variables) {
@@ -388,21 +386,18 @@ final class HierarchicalUriComponents extends UriComponents {
 	public String toUriString() {
 		StringBuilder uriBuilder = new StringBuilder();
 		if (getScheme() != null) {
-			uriBuilder.append(getScheme());
-			uriBuilder.append(':');
+			uriBuilder.append(getScheme()).append(':');
 		}
 		if (this.userInfo != null || this.host != null) {
 			uriBuilder.append("//");
 			if (this.userInfo != null) {
-				uriBuilder.append(this.userInfo);
-				uriBuilder.append('@');
+				uriBuilder.append(this.userInfo).append('@');
 			}
 			if (this.host != null) {
-				uriBuilder.append(host);
+				uriBuilder.append(this.host);
 			}
 			if (getPort() != -1) {
-				uriBuilder.append(':');
-				uriBuilder.append(port);
+				uriBuilder.append(':').append(this.port);
 			}
 		}
 		String path = getPath();
@@ -414,12 +409,10 @@ final class HierarchicalUriComponents extends UriComponents {
 		}
 		String query = getQuery();
 		if (query != null) {
-			uriBuilder.append('?');
-			uriBuilder.append(query);
+			uriBuilder.append('?').append(query);
 		}
 		if (getFragment() != null) {
-			uriBuilder.append('#');
-			uriBuilder.append(getFragment());
+			uriBuilder.append('#').append(getFragment());
 		}
 		return uriBuilder.toString();
 	}
@@ -428,7 +421,7 @@ final class HierarchicalUriComponents extends UriComponents {
 	public URI toUri() {
 		try {
 			if (this.encoded) {
-				return new URI(toString());
+				return new URI(toUriString());
 			}
 			else {
 				String path = getPath();