diff --git a/httpclient5-cache/src/test/java/org/apache/hc/client5/http/impl/cache/HttpTestUtils.java b/httpclient5-cache/src/test/java/org/apache/hc/client5/http/impl/cache/HttpTestUtils.java
index c65c16a42..9815aabc2 100644
--- a/httpclient5-cache/src/test/java/org/apache/hc/client5/http/impl/cache/HttpTestUtils.java
+++ b/httpclient5-cache/src/test/java/org/apache/hc/client5/http/impl/cache/HttpTestUtils.java
@@ -46,6 +46,7 @@ import org.apache.hc.core5.http.HttpRequest;
 import org.apache.hc.core5.http.HttpResponse;
 import org.apache.hc.core5.http.HttpStatus;
 import org.apache.hc.core5.http.HttpVersion;
+import org.apache.hc.core5.http.Method;
 import org.apache.hc.core5.http.ProtocolVersion;
 import org.apache.hc.core5.http.io.entity.ByteArrayEntity;
 import org.apache.hc.core5.http.message.BasicClassicHttpRequest;
@@ -353,11 +354,11 @@ public class HttpTestUtils {
     }
 
     public static ClassicHttpRequest makeDefaultRequest() {
-        return new BasicClassicHttpRequest("GET", "/");
+        return new BasicClassicHttpRequest(Method.GET.toString(), "/");
     }
 
     public static ClassicHttpRequest makeDefaultHEADRequest() {
-        return new BasicClassicHttpRequest("HEAD", "/");
+        return new BasicClassicHttpRequest(Method.HEAD.toString(), "/");
     }
 
     public static ClassicHttpResponse make500Response() {
diff --git a/httpclient5/src/main/java/org/apache/hc/client5/http/impl/async/AsyncConnectExec.java b/httpclient5/src/main/java/org/apache/hc/client5/http/impl/async/AsyncConnectExec.java
index 10f8ebff7..fca3b742f 100644
--- a/httpclient5/src/main/java/org/apache/hc/client5/http/impl/async/AsyncConnectExec.java
+++ b/httpclient5/src/main/java/org/apache/hc/client5/http/impl/async/AsyncConnectExec.java
@@ -57,6 +57,7 @@ import org.apache.hc.core5.http.HttpRequest;
 import org.apache.hc.core5.http.HttpResponse;
 import org.apache.hc.core5.http.HttpStatus;
 import org.apache.hc.core5.http.HttpVersion;
+import org.apache.hc.core5.http.Method;
 import org.apache.hc.core5.http.message.BasicHttpRequest;
 import org.apache.hc.core5.http.message.StatusLine;
 import org.apache.hc.core5.http.nio.AsyncDataConsumer;
@@ -332,7 +333,7 @@ public final class AsyncConnectExec implements AsyncExecChainHandler {
 
         final AuthExchange proxyAuthExchange = proxy != null ? clientContext.getAuthExchange(proxy) : new AuthExchange();
 
-        final HttpRequest connect = new BasicHttpRequest("CONNECT", nextHop, nextHop.toHostString());
+        final HttpRequest connect = new BasicHttpRequest(Method.CONNECT, nextHop, nextHop.toHostString());
         connect.setVersion(HttpVersion.HTTP_1_1);
 
         proxyHttpProcessor.process(connect, null, clientContext);
diff --git a/httpclient5/src/main/java/org/apache/hc/client5/http/impl/classic/ConnectExec.java b/httpclient5/src/main/java/org/apache/hc/client5/http/impl/classic/ConnectExec.java
index e0a410acd..45a7ae762 100644
--- a/httpclient5/src/main/java/org/apache/hc/client5/http/impl/classic/ConnectExec.java
+++ b/httpclient5/src/main/java/org/apache/hc/client5/http/impl/classic/ConnectExec.java
@@ -56,6 +56,7 @@ import org.apache.hc.core5.http.HttpHost;
 import org.apache.hc.core5.http.HttpRequest;
 import org.apache.hc.core5.http.HttpStatus;
 import org.apache.hc.core5.http.HttpVersion;
+import org.apache.hc.core5.http.Method;
 import org.apache.hc.core5.http.io.entity.EntityUtils;
 import org.apache.hc.core5.http.message.BasicClassicHttpRequest;
 import org.apache.hc.core5.http.message.StatusLine;
@@ -209,7 +210,7 @@ public final class ConnectExec implements ExecChainHandler {
         ClassicHttpResponse response = null;
 
         final String authority = target.toHostString();
-        final ClassicHttpRequest connect = new BasicClassicHttpRequest("CONNECT", target, authority);
+        final ClassicHttpRequest connect = new BasicClassicHttpRequest(Method.CONNECT, target, authority);
         connect.setVersion(HttpVersion.HTTP_1_1);
 
         this.proxyHttpProcessor.process(connect, null, context);
diff --git a/httpclient5/src/main/java/org/apache/hc/client5/http/impl/classic/ProxyClient.java b/httpclient5/src/main/java/org/apache/hc/client5/http/impl/classic/ProxyClient.java
index fa0113776..b7e63ef8c 100644
--- a/httpclient5/src/main/java/org/apache/hc/client5/http/impl/classic/ProxyClient.java
+++ b/httpclient5/src/main/java/org/apache/hc/client5/http/impl/classic/ProxyClient.java
@@ -61,6 +61,7 @@ import org.apache.hc.core5.http.HttpEntity;
 import org.apache.hc.core5.http.HttpException;
 import org.apache.hc.core5.http.HttpHeaders;
 import org.apache.hc.core5.http.HttpHost;
+import org.apache.hc.core5.http.Method;
 import org.apache.hc.core5.http.config.CharCodingConfig;
 import org.apache.hc.core5.http.config.Http1Config;
 import org.apache.hc.core5.http.config.Lookup;
@@ -158,7 +159,7 @@ public class ProxyClient {
         final HttpContext context = new BasicHttpContext();
         ClassicHttpResponse response;
 
-        final ClassicHttpRequest connect = new BasicClassicHttpRequest("CONNECT", host.toHostString());
+        final ClassicHttpRequest connect = new BasicClassicHttpRequest(Method.CONNECT, host.toHostString());
 
         final BasicCredentialsProvider credsProvider = new BasicCredentialsProvider();
         credsProvider.setCredentials(new AuthScope(proxy), credentials);
diff --git a/httpclient5/src/main/java/org/apache/hc/client5/http/protocol/RequestAddCookies.java b/httpclient5/src/main/java/org/apache/hc/client5/http/protocol/RequestAddCookies.java
index a0d926119..7bd519941 100644
--- a/httpclient5/src/main/java/org/apache/hc/client5/http/protocol/RequestAddCookies.java
+++ b/httpclient5/src/main/java/org/apache/hc/client5/http/protocol/RequestAddCookies.java
@@ -47,6 +47,7 @@ import org.apache.hc.core5.http.Header;
 import org.apache.hc.core5.http.HttpException;
 import org.apache.hc.core5.http.HttpRequest;
 import org.apache.hc.core5.http.HttpRequestInterceptor;
+import org.apache.hc.core5.http.Method;
 import org.apache.hc.core5.http.config.Lookup;
 import org.apache.hc.core5.http.protocol.HttpContext;
 import org.apache.hc.core5.net.URIAuthority;
@@ -78,7 +79,7 @@ public class RequestAddCookies implements HttpRequestInterceptor {
         Args.notNull(context, "HTTP context");
 
         final String method = request.getMethod();
-        if (method.equalsIgnoreCase("CONNECT") || method.equalsIgnoreCase("TRACE")) {
+        if (Method.CONNECT.isSame(method) || Method.TRACE.isSame(method)) {
             return;
         }
 
diff --git a/httpclient5/src/main/java/org/apache/hc/client5/http/protocol/RequestClientConnControl.java b/httpclient5/src/main/java/org/apache/hc/client5/http/protocol/RequestClientConnControl.java
index 563a5fb7e..2798c5801 100644
--- a/httpclient5/src/main/java/org/apache/hc/client5/http/protocol/RequestClientConnControl.java
+++ b/httpclient5/src/main/java/org/apache/hc/client5/http/protocol/RequestClientConnControl.java
@@ -38,6 +38,7 @@ import org.apache.hc.core5.http.HttpException;
 import org.apache.hc.core5.http.HttpHeaders;
 import org.apache.hc.core5.http.HttpRequest;
 import org.apache.hc.core5.http.HttpRequestInterceptor;
+import org.apache.hc.core5.http.Method;
 import org.apache.hc.core5.http.protocol.HttpContext;
 import org.apache.hc.core5.util.Args;
 import org.slf4j.Logger;
@@ -65,7 +66,7 @@ public class RequestClientConnControl implements HttpRequestInterceptor {
         Args.notNull(request, "HTTP request");
 
         final String method = request.getMethod();
-        if (method.equalsIgnoreCase("CONNECT")) {
+        if (Method.CONNECT.isSame(method)) {
             return;
         }
 
diff --git a/httpclient5/src/main/java/org/apache/hc/client5/http/protocol/RequestDefaultHeaders.java b/httpclient5/src/main/java/org/apache/hc/client5/http/protocol/RequestDefaultHeaders.java
index 3f4e02c3f..6d31b24c5 100644
--- a/httpclient5/src/main/java/org/apache/hc/client5/http/protocol/RequestDefaultHeaders.java
+++ b/httpclient5/src/main/java/org/apache/hc/client5/http/protocol/RequestDefaultHeaders.java
@@ -37,6 +37,7 @@ import org.apache.hc.core5.http.Header;
 import org.apache.hc.core5.http.HttpException;
 import org.apache.hc.core5.http.HttpRequest;
 import org.apache.hc.core5.http.HttpRequestInterceptor;
+import org.apache.hc.core5.http.Method;
 import org.apache.hc.core5.http.protocol.HttpContext;
 import org.apache.hc.core5.util.Args;
 
@@ -68,7 +69,7 @@ public class RequestDefaultHeaders implements HttpRequestInterceptor {
         Args.notNull(request, "HTTP request");
 
         final String method = request.getMethod();
-        if (method.equalsIgnoreCase("CONNECT")) {
+        if (Method.CONNECT.isSame(method)) {
             return;
         }