Use datatracker.ietf.org when referring to IETF RFCs and drafts (#3374)

Related issue: #3246 Motivation: IETF now recommends referring to their new Datatracker web site rather than `tools.ietf.org`, `www.ietf.org`, `whatwg.org` or `www.rfc-editors.org`. Modifications: - Replace all IETF RFC and draft URLs with `https://datatracker.ietf.org/`. Result: - Hyperlinked IETF RFC/draft pages look better.
line · Mar 9, 2021 · 32eabd2 · 32eabd2
1 parent 9e17885
commit 32eabd2
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Showing 67 changed files with 212 additions and 195 deletions.
diff --git a/bucket4j/src/main/java/com/linecorp/armeria/common/throttling/ThrottlingHeaders.java b/bucket4j/src/main/java/com/linecorp/armeria/common/throttling/ThrottlingHeaders.java
@@ -27,8 +27,8 @@
 public interface ThrottlingHeaders {
     /**
      * Describes
-     * <a href="https://tools.ietf.org/id/draft-polli-ratelimit-headers-00.html">RateLimit Header Scheme for HTTP</a>.
-     * For example:
+     * <a href="https://datatracker.ietf.org/doc/draft-ietf-httpapi-ratelimit-headers/">RateLimit Header Fields
+     * for HTTP</a>. For example:
      * <pre>{@code
      * RateLimit-Limit: 10
      * RateLimit-Remaining: 1

diff --git a/bucket4j/src/main/java/com/linecorp/armeria/server/throttling/bucket4j/BandwidthLimit.java b/bucket4j/src/main/java/com/linecorp/armeria/server/throttling/bucket4j/BandwidthLimit.java
@@ -80,7 +80,8 @@ public static BandwidthLimit of(long limit, Duration period) {
      * Returns a newly created {@link BandwidthLimit}. Computes {@code limit}, {@code overdraftLimit},
      * {@code initialSize} and {@code period} out of a semicolon-separated {@code specification} string
      * that conforms to the following format,
-     * as per <a href="https://tools.ietf.org/id/draft-polli-ratelimit-headers-00.html">RateLimit Header Scheme for HTTP</a>:
+     * as per <a href="https://datatracker.ietf.org/doc/draft-ietf-httpapi-ratelimit-headers/">RateLimit Header
+     * Fields for HTTP</a>:
      * <pre>{@code
      * <limit>;window=<period(in seconds)>[;burst=<overdraftLimit>][;initial=<initialSize>]
      * }</pre>
@@ -195,7 +196,8 @@ public String toString() {
 
     /**
      * Returns a string representation of the {@link BandwidthLimit} in the following format,
-     * as per <a href="https://tools.ietf.org/id/draft-polli-ratelimit-headers-00.html">RateLimit Header Scheme for HTTP</a>:
+     * as per <a href="https://datatracker.ietf.org/doc/draft-ietf-httpapi-ratelimit-headers/">RateLimit Header
+     * Fields for HTTP</a>:
      * <pre>{@code
      * <limit>;window=<period(in seconds)>[;burst=<overdraftLimit>][;policy="token bucket"]
      * }</pre>

diff --git a/bucket4j/src/main/java/com/linecorp/armeria/server/throttling/bucket4j/TokenBucket.java b/bucket4j/src/main/java/com/linecorp/armeria/server/throttling/bucket4j/TokenBucket.java
@@ -42,7 +42,8 @@ public static TokenBucketBuilder builder() {
     /**
      * Returns a newly created {@link TokenBucket}. Computes a set of {@link BandwidthLimit} out of
      * a comma-separated {@code specification} string that conforms to the following format,
-     * as per <a href="https://tools.ietf.org/id/draft-polli-ratelimit-headers-00.html">RateLimit Header Scheme for HTTP</a>:
+     * as per <a href="https://datatracker.ietf.org/doc/draft-ietf-httpapi-ratelimit-headers/">RateLimit Header
+     * Fields for HTTP</a>:
      * <pre>{@code
      * <bandwidth limit 1>[, <bandwidth limit 2>[, etc.]]
      * }</pre>
@@ -135,7 +136,8 @@ BandwidthLimit lowestLimit() {
 
     /**
      * Returns a string representation of the multiple limits in the following format,
-     * as per <a href="https://tools.ietf.org/id/draft-polli-ratelimit-headers-00.html">RateLimit Header Scheme for HTTP</a>:
+     * as per <a href="https://datatracker.ietf.org/doc/draft-ietf-httpapi-ratelimit-headers/">RateLimit Header
+     * Fields for HTTP</a>:
      * <pre>{@code
      * <lowest limit>, <first limit>;window=<first period(in seconds)>;burst=<first overdraftLimit>,
      *                 <second limit>;window=<second period(in seconds)>;burst=<second overdraftLimit>, etc.

diff --git a/bucket4j/src/main/java/com/linecorp/armeria/server/throttling/bucket4j/TokenBucketSpec.java b/bucket4j/src/main/java/com/linecorp/armeria/server/throttling/bucket4j/TokenBucketSpec.java
@@ -33,7 +33,8 @@
 /**
  * A specification of a {@link TokenBucket} configuration represented by a string. The string syntax is
  * a series of comma-separated {@link BandwidthLimit} configurations and each values is semicolon-separated,
- * as per <a href="https://tools.ietf.org/id/draft-polli-ratelimit-headers-00.html">RateLimit Header Scheme for HTTP</a>.
+ * as per <a href="https://datatracker.ietf.org/doc/draft-ietf-httpapi-ratelimit-headers/">RateLimit Header
+ * Fields for HTTP</a>.
  *
  * @see #parseTokenBucket(String) for detailed format of the specification.
  */
@@ -143,7 +144,9 @@ static TokenBucket parseTokenBucket(String specification) {
      * For example: "100;window=60;burst=1000".
      * <br>
      * This method used to compose Quota Policy response header to inform the client about rate
-     * limiting policy as per <a href="https://tools.ietf.org/id/draft-polli-ratelimit-headers-00.html">RateLimit Header Scheme for HTTP</a>.
+     * limiting policy as per
+     * <a href="https://datatracker.ietf.org/doc/draft-ietf-httpapi-ratelimit-headers/">RateLimit Header Fields
+     * for HTTP</a>.
      *
      * @return A {@link String} representation of the {@link BandwidthLimit}.
      */
@@ -174,7 +177,9 @@ static String toString(@Nullable BandwidthLimit bandwidthLimit) {
      * For example: "100;window=60;burst=1000, 5000;window=3600".
      * <br>
      * This method used to compose Quota Policy response header to inform the client about rate
-     * limiting policy as per <a href="https://tools.ietf.org/id/draft-polli-ratelimit-headers-00.html">RateLimit Header Scheme for HTTP</a>.
+     * limiting policy as per
+     * <a href="https://datatracker.ietf.org/doc/draft-ietf-httpapi-ratelimit-headers/">RateLimit Header Fields
+     * for HTTP</a>.
      *
      * @return A {@link String} representation of the {@link TokenBucket}.
      */

diff --git a/core/src/main/java/com/linecorp/armeria/client/ClientFactoryBuilder.java b/core/src/main/java/com/linecorp/armeria/client/ClientFactoryBuilder.java
@@ -306,12 +306,12 @@ public ClientFactoryBuilder tlsCustomizer(Consumer<? super SslContextBuilder> tl
 
     /**
      * Allows the bad cipher suites listed in
-     * <a href="https://tools.ietf.org/html/rfc7540#appendix-A">RFC7540</a> for TLS handshake.
+     * <a href="https://datatracker.ietf.org/doc/html/rfc7540#appendix-A">RFC7540</a> for TLS handshake.
      *
      * <p>Note that enabling this option increases the security risk of your connection.
      * Use it only when you must communicate with a legacy system that does not support
      * secure cipher suites.
-     * See <a href="https://tools.ietf.org/html/rfc7540#section-9.2.2">Section 9.2.2, RFC7540</a> for
+     * See <a href="https://datatracker.ietf.org/doc/html/rfc7540#section-9.2.2">Section 9.2.2, RFC7540</a> for
      * more information. This option is disabled by default.
      *
      * @deprecated It's not recommended to enable this option. Use it only when you have no other way to
@@ -324,12 +324,12 @@ public ClientFactoryBuilder tlsAllowUnsafeCiphers() {
 
     /**
      * Allows the bad cipher suites listed in
-     * <a href="https://tools.ietf.org/html/rfc7540#appendix-A">RFC7540</a> for TLS handshake.
+     * <a href="https://datatracker.ietf.org/doc/html/rfc7540#appendix-A">RFC7540</a> for TLS handshake.
      *
      * <p>Note that enabling this option increases the security risk of your connection.
      * Use it only when you must communicate with a legacy system that does not support
      * secure cipher suites.
-     * See <a href="https://tools.ietf.org/html/rfc7540#section-9.2.2">Section 9.2.2, RFC7540</a> for
+     * See <a href="https://datatracker.ietf.org/doc/html/rfc7540#section-9.2.2">Section 9.2.2, RFC7540</a> for
      * more information. This option is disabled by default.
      *
      * @param tlsAllowUnsafeCiphers Whether to allow the unsafe ciphers
@@ -379,7 +379,7 @@ public ClientFactoryBuilder domainNameResolverCustomizer(
     }
 
     /**
-     * Sets the <a href="https://tools.ietf.org/html/rfc7540#section-6.9.2">initial connection flow-control
+     * Sets the <a href="https://datatracker.ietf.org/doc/html/rfc7540#section-6.9.2">initial connection flow-control
      * window size</a>. The HTTP/2 connection is first established with
      * {@value Http2CodecUtil#DEFAULT_WINDOW_SIZE} bytes of connection flow-control window size,
      * and it is changed if and only if {@code http2InitialConnectionWindowSize} is set.
@@ -396,7 +396,7 @@ public ClientFactoryBuilder http2InitialConnectionWindowSize(int http2InitialCon
     }
 
     /**
-     * Sets the <a href="https://tools.ietf.org/html/rfc7540#section-6.5.2">SETTINGS_INITIAL_WINDOW_SIZE</a>
+     * Sets the <a href="https://datatracker.ietf.org/doc/html/rfc7540#section-6.5.2">SETTINGS_INITIAL_WINDOW_SIZE</a>
      * for HTTP/2 stream-level flow control. Note that this setting affects the window size of all streams,
      * not the connection-level window size.
      *
@@ -411,7 +411,7 @@ public ClientFactoryBuilder http2InitialStreamWindowSize(int http2InitialStreamW
     }
 
     /**
-     * Sets the <a href="https://tools.ietf.org/html/rfc7540#section-6.5.2">SETTINGS_MAX_FRAME_SIZE</a>
+     * Sets the <a href="https://datatracker.ietf.org/doc/html/rfc7540#section-6.5.2">SETTINGS_MAX_FRAME_SIZE</a>
      * that indicates the size of the largest frame payload that this client is willing to receive.
      */
     public ClientFactoryBuilder http2MaxFrameSize(int http2MaxFrameSize) {
@@ -424,7 +424,7 @@ public ClientFactoryBuilder http2MaxFrameSize(int http2MaxFrameSize) {
     }
 
     /**
-     * Sets the <a href="https://tools.ietf.org/html/rfc7540#section-6.5.2">SETTINGS_MAX_HEADER_LIST_SIZE</a>
+     * Sets the <a href="https://datatracker.ietf.org/doc/html/rfc7540#section-6.5.2">SETTINGS_MAX_HEADER_LIST_SIZE</a>
      * that indicates the maximum size of header list that the client is prepared to accept, in octets.
      */
     public ClientFactoryBuilder http2MaxHeaderListSize(long http2MaxHeaderListSize) {
@@ -494,9 +494,9 @@ public ClientFactoryBuilder idleTimeoutMillis(long idleTimeoutMillis) {
     /**
      * Sets the PING interval in milliseconds.
      * When neither read nor write was performed for the given {@code pingIntervalMillis},
-     * a <a href="https://httpwg.org/specs/rfc7540.html#PING">PING</a> frame is sent for HTTP/2 or
-     * an <a href="https://tools.ietf.org/html/rfc7231#section-4.3.7">OPTIONS</a> request with an asterisk ("*")
-     * is sent for HTTP/1.
+     * a <a href="https://datatracker.ietf.org/doc/html/rfc7540#section-6.7">PING</a> frame is sent for HTTP/2
+     * or an <a href="https://datatracker.ietf.org/doc/html/rfc7231#section-4.3.7">OPTIONS</a> request with
+     * an asterisk ("*") is sent for HTTP/1.
      *
      * <p>Note that this settings is only in effect when {@link #idleTimeoutMillis(long)}} or
      * {@link #idleTimeout(Duration)} is greater than the specified PING interval.
@@ -518,9 +518,9 @@ public ClientFactoryBuilder pingIntervalMillis(long pingIntervalMillis) {
     /**
      * Sets the PING interval.
      * When neither read nor write was performed for the given {@code pingInterval},
-     * a <a href="https://httpwg.org/specs/rfc7540.html#PING">PING</a> frame is sent for HTTP/2 or
-     * an <a href="https://tools.ietf.org/html/rfc7231#section-4.3.7">OPTIONS</a> request with an asterisk ("*")
-     * is sent for HTTP/1.
+     * a <a href="https://datatracker.ietf.org/doc/html/rfc7540#section-6.7">PING</a> frame is sent for HTTP/2
+     * or an <a href="https://datatracker.ietf.org/doc/html/rfc7231#section-4.3.7">OPTIONS</a> request with
+     * an asterisk ("*") is sent for HTTP/1.
      *
      * <p>Note that this settings is only in effect when {@link #idleTimeoutMillis(long)}} or
      * {@link #idleTimeout(Duration)} is greater than the specified PING interval.

diff --git a/core/src/main/java/com/linecorp/armeria/client/ClientFactoryOptions.java b/core/src/main/java/com/linecorp/armeria/client/ClientFactoryOptions.java
@@ -81,12 +81,12 @@ public final class ClientFactoryOptions
 
     /**
      * Whether to allow the bad cipher suites listed in
-     * <a href="https://tools.ietf.org/html/rfc7540#appendix-A">RFC7540</a> for TLS handshake.
+     * <a href="https://datatracker.ietf.org/doc/html/rfc7540#appendix-A">RFC7540</a> for TLS handshake.
      *
      * <p>Note that enabling this option increases the security risk of your connection.
      * Use it only when you must communicate with a legacy system that does not support
      * secure cipher suites.
-     * See <a href="https://tools.ietf.org/html/rfc7540#section-9.2.2">Section 9.2.2, RFC7540</a> for
+     * See <a href="https://datatracker.ietf.org/doc/html/rfc7540#section-9.2.2">Section 9.2.2, RFC7540</a> for
      * more information.
      *
      * @deprecated It's not recommended to enable this option. Use it only when you have no other way to
@@ -106,30 +106,30 @@ public final class ClientFactoryOptions
                                        eventLoopGroup -> new DnsResolverGroupBuilder().build(eventLoopGroup));
 
     /**
-     * The HTTP/2 <a href="https://tools.ietf.org/html/rfc7540#section-6.9.2">initial connection flow-control
+     * The HTTP/2 <a href="https://datatracker.ietf.org/doc/html/rfc7540#section-6.9.2">initial connection flow-control
      * window size</a>.
      */
     public static final ClientFactoryOption<Integer> HTTP2_INITIAL_CONNECTION_WINDOW_SIZE =
             ClientFactoryOption.define("HTTP2_INITIAL_CONNECTION_WINDOW_SIZE",
                                        Flags.defaultHttp2InitialConnectionWindowSize());
 
     /**
-     * The <a href="https://tools.ietf.org/html/rfc7540#section-6.5.2">SETTINGS_INITIAL_WINDOW_SIZE</a>
+     * The <a href="https://datatracker.ietf.org/doc/html/rfc7540#section-6.5.2">SETTINGS_INITIAL_WINDOW_SIZE</a>
      * for HTTP/2 stream-level flow control.
      */
     public static final ClientFactoryOption<Integer> HTTP2_INITIAL_STREAM_WINDOW_SIZE =
             ClientFactoryOption.define("HTTP2_INITIAL_STREAM_WINDOW_SIZE",
                                        Flags.defaultHttp2InitialStreamWindowSize());
 
     /**
-     * The <a href="https://tools.ietf.org/html/rfc7540#section-6.5.2">SETTINGS_MAX_FRAME_SIZE</a>
+     * The <a href="https://datatracker.ietf.org/doc/html/rfc7540#section-6.5.2">SETTINGS_MAX_FRAME_SIZE</a>
      * that indicates the size of the largest frame payload that this client is willing to receive.
      */
     public static final ClientFactoryOption<Integer> HTTP2_MAX_FRAME_SIZE =
             ClientFactoryOption.define("HTTP2_MAX_FRAME_SIZE", Flags.defaultHttp2MaxFrameSize());
 
     /**
-     * The HTTP/2 <a href="https://tools.ietf.org/html/rfc7540#section-6.5.2">SETTINGS_MAX_HEADER_LIST_SIZE</a>
+     * The HTTP/2 <a href="https://datatracker.ietf.org/doc/html/rfc7540#section-6.5.2">SETTINGS_MAX_HEADER_LIST_SIZE</a>
      * that indicates the maximum size of header list that the client is prepared to accept, in octets.
      */
     public static final ClientFactoryOption<Long> HTTP2_MAX_HEADER_LIST_SIZE =
@@ -163,9 +163,9 @@ public final class ClientFactoryOptions
     /**
      * The PING interval in milliseconds.
      * When neither read nor write was performed for the specified period of time,
-     * a <a href="https://httpwg.org/specs/rfc7540.html#PING">PING</a> frame is sent for HTTP/2 or
-     * an <a href="https://tools.ietf.org/html/rfc7231#section-4.3.7">OPTIONS</a> request with an asterisk ("*")
-     * is sent for HTTP/1.
+     * a <a href="https://datatracker.ietf.org/doc/html/rfc7540#section-6.7">PING</a> frame is sent for HTTP/2
+     * or an <a href="https://datatracker.ietf.org/doc/html/rfc7231#section-4.3.7">OPTIONS</a> request with
+     * an asterisk ("*") is sent for HTTP/1.
      */
     public static final ClientFactoryOption<Long> PING_INTERVAL_MILLIS =
             ClientFactoryOption.define("PING_INTERVAL_MILLIS", Flags.defaultPingIntervalMillis());
@@ -381,31 +381,31 @@ public Consumer<? super SslContextBuilder> tlsCustomizer() {
     }
 
     /**
-     * Returns the HTTP/2 <a href="https://tools.ietf.org/html/rfc7540#section-6.9.2">initial connection
+     * Returns the HTTP/2 <a href="https://datatracker.ietf.org/doc/html/rfc7540#section-6.9.2">initial connection
      * flow-control window size</a>.
      */
     public int http2InitialConnectionWindowSize() {
         return get(HTTP2_INITIAL_CONNECTION_WINDOW_SIZE);
     }
 
     /**
-     * Returns the <a href="https://tools.ietf.org/html/rfc7540#section-6.5.2">SETTINGS_INITIAL_WINDOW_SIZE</a>
+     * Returns the <a href="https://datatracker.ietf.org/doc/html/rfc7540#section-6.5.2">SETTINGS_INITIAL_WINDOW_SIZE</a>
      * for HTTP/2 stream-level flow control.
      */
     public int http2InitialStreamWindowSize() {
         return get(HTTP2_INITIAL_STREAM_WINDOW_SIZE);
     }
 
     /**
-     * Returns the <a href="https://tools.ietf.org/html/rfc7540#section-6.5.2">SETTINGS_MAX_FRAME_SIZE</a>
+     * Returns the <a href="https://datatracker.ietf.org/doc/html/rfc7540#section-6.5.2">SETTINGS_MAX_FRAME_SIZE</a>
      * that indicates the size of the largest frame payload that this client is willing to receive.
      */
     public int http2MaxFrameSize() {
         return get(HTTP2_MAX_FRAME_SIZE);
     }
 
     /**
-     * Returns the HTTP/2 <a href="https://tools.ietf.org/html/rfc7540#section-6.5.2">
+     * Returns the HTTP/2 <a href="https://datatracker.ietf.org/doc/html/rfc7540#section-6.5.2">
      * SETTINGS_MAX_HEADER_LIST_SIZE</a> that indicates the maximum size of header list
      * that the client is prepared to accept, in octets.
      */
@@ -444,9 +444,9 @@ public long idleTimeoutMillis() {
     /**
      * Returns the PING interval in milliseconds.
      * When neither read nor write was performed for the specified period of time,
-     * a <a href="https://httpwg.org/specs/rfc7540.html#PING">PING</a> frame is sent for HTTP/2 or
-     * an <a href="https://tools.ietf.org/html/rfc7231#section-4.3.7">OPTIONS</a> request with an asterisk ("*")
-     * is sent for HTTP/1.
+     * a <a href="https://datatracker.ietf.org/doc/html/rfc7540#section-6.7">PING</a> frame is sent for HTTP/2
+     * or an <a href="https://datatracker.ietf.org/doc/html/rfc7231#section-4.3.7">OPTIONS</a> request with
+     * an asterisk ("*") is sent for HTTP/1.
      */
     public long pingIntervalMillis() {
         return get(PING_INTERVAL_MILLIS);
@@ -516,12 +516,12 @@ public Http1HeaderNaming http1HeaderNaming() {
 
     /**
      * Returns whether to allow the bad cipher suites listed in
-     * <a href="https://tools.ietf.org/html/rfc7540#appendix-A">RFC7540</a> for TLS handshake.
+     * <a href="https://datatracker.ietf.org/doc/html/rfc7540#appendix-A">RFC7540</a> for TLS handshake.
      *
      * <p>Note that enabling this option increases the security risk of your connection.
      * Use it only when you must communicate with a legacy system that does not support
      * secure cipher suites.
-     * See <a href="https://tools.ietf.org/html/rfc7540#section-9.2.2">Section 9.2.2, RFC7540</a> for
+     * See <a href="https://datatracker.ietf.org/doc/html/rfc7540#section-9.2.2">Section 9.2.2, RFC7540</a> for
      * more information.
      */
     public boolean tlsAllowUnsafeCiphers() {

diff --git a/core/src/main/java/com/linecorp/armeria/client/ClientHttp1ObjectEncoder.java b/core/src/main/java/com/linecorp/armeria/client/ClientHttp1ObjectEncoder.java
@@ -78,7 +78,7 @@ private HttpObject convertHeaders(RequestHeaders headers, boolean endStream) {
             nettyHeaders.remove(HttpHeaderNames.TRANSFER_ENCODING);
 
             // Set or remove the 'content-length' header depending on request method.
-            // See: https://tools.ietf.org/html/rfc7230#section-3.3.2
+            // See: https://datatracker.ietf.org/doc/html/rfc7230#section-3.3.2
             //
             // > A user agent SHOULD send a Content-Length in a request message when
             // > no Transfer-Encoding is sent and the request method defines a meaning

diff --git a/core/src/main/java/com/linecorp/armeria/client/ClientRequestContext.java b/core/src/main/java/com/linecorp/armeria/client/ClientRequestContext.java
@@ -269,7 +269,7 @@ ClientRequestContext newDerivedContext(RequestId id, @Nullable HttpRequest req,
 
     /**
      * Returns the fragment part of the URI of the current {@link Request}, as defined in
-     * <a href="https://tools.ietf.org/html/rfc3986#section-3.5">the section 3.5 of RFC3986</a>.
+     * <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.5">the section 3.5 of RFC3986</a>.
      *
      * @return the fragment part of the request URI, or {@code null} if no fragment was specified
      */

diff --git a/core/src/main/java/com/linecorp/armeria/client/DnsResolverGroupBuilder.java b/core/src/main/java/com/linecorp/armeria/client/DnsResolverGroupBuilder.java
@@ -293,7 +293,7 @@ public DnsResolverGroupBuilder ndots(int ndots) {
 
     /**
      * Sets if the domain and host names should be decoded to unicode when received.
-     * See <a href="https://tools.ietf.org/html/rfc3492">rfc3492</a>. This flag is enabled by default.
+     * See <a href="https://datatracker.ietf.org/doc/rfc3492/">rfc3492</a>. This flag is enabled by default.
      *
      * @see DnsNameResolverBuilder#decodeIdn(boolean)
      */

diff --git a/core/src/main/java/com/linecorp/armeria/client/Endpoint.java b/core/src/main/java/com/linecorp/armeria/client/Endpoint.java
@@ -64,7 +64,7 @@ public final class Endpoint implements Comparable<Endpoint>, EndpointGroup {
 
     /**
      * Validator for the scheme part of the URI, as defined in
-     * <a href="https://tools.ietf.org/html/rfc3986#section-3.1">the section 3.1 of RFC3986</a>.
+     * <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.1">the section 3.1 of RFC3986</a>.
      */
     private static final Predicate<String> SCHEME_VALIDATOR =
             scheme -> Pattern.compile("^([a-z][a-z0-9+\\-.]*)").matcher(scheme).matches();