fix HeaderAuthorizationFilter multimap usage

pom.xml

@@ -6,7 +6,7 @@
 	
 	<groupId>com.inteligr8</groupId>
 	<artifactId>common-rest-client</artifactId>
-	<version>2.0-SNAPSHOT</version>
+	<version>3.0-SNAPSHOT</version>
 	<packaging>jar</packaging>
 
 	<name>ReST API Client for Java</name>
@@ -40,16 +40,20 @@
 
 	<properties>
 		<project.build.sourceEncoding>utf-8</project.build.sourceEncoding>
-		<maven.compiler.source>8</maven.compiler.source>
-		<maven.compiler.target>8</maven.compiler.target>
+		<maven.compiler.source>11</maven.compiler.source>
+		<maven.compiler.target>11</maven.compiler.target>
 
-		<junit.version>5.7.2</junit.version>
-		<spring.version>5.2.14.RELEASE</spring.version>
-		<jersey.version>2.35</jersey.version>
-		<cxf.version>3.3.2</cxf.version>
+		<junit.version>5.12.0</junit.version>
+		<spring.version>6.0.23</spring.version>
+		<jackson.version>2.17.3</jackson.version>
 	</properties>
 
 	<dependencies>
+		<dependency>
+			<groupId>jakarta.annotation</groupId>
+			<artifactId>jakarta.annotation-api</artifactId>
+			<version>2.1.1</version>
+		</dependency>
 		<dependency>
 			<groupId>org.springframework</groupId>
 			<artifactId>spring-context</artifactId>
@@ -58,27 +62,32 @@
 		<dependency>
 			<groupId>com.fasterxml.jackson.core</groupId>
 			<artifactId>jackson-databind</artifactId>
-			<version>2.12.2</version>
+			<version>${jackson.version}</version>
 		</dependency>
 		<dependency>
-			<groupId>com.fasterxml.jackson.jaxrs</groupId>
-			<artifactId>jackson-jaxrs-json-provider</artifactId>
-			<version>2.12.2</version>
+			<groupId>com.fasterxml.jackson.jakarta.rs</groupId>
+			<artifactId>jackson-jakarta-rs-json-provider</artifactId>
+			<version>${jackson.version}</version>
 		</dependency>
 		<dependency>
 			<groupId>com.fasterxml.jackson.datatype</groupId>
 			<artifactId>jackson-datatype-jsr310</artifactId>
-			<version>2.12.2</version>
+			<version>${jackson.version}</version>
+		</dependency>
+		<dependency>
+			<groupId>org.apache.commons</groupId>
+			<artifactId>commons-lang3</artifactId>
+			<version>3.17.0</version>
 		</dependency>
 		<dependency>
 			<groupId>org.slf4j</groupId>
 			<artifactId>slf4j-api</artifactId>
-			<version>1.7.29</version>
+			<version>2.0.17</version>
 		</dependency>
 		<dependency>
 			<groupId>jakarta.ws.rs</groupId>
 			<artifactId>jakarta.ws.rs-api</artifactId>
-			<version>2.1.6</version>
+			<version>3.1.0</version>
 		</dependency>
 		<dependency>
 			<groupId>org.junit.jupiter</groupId>
@@ -95,7 +104,7 @@
 		<dependency>
 			<groupId>org.apache.httpcomponents</groupId>
 			<artifactId>httpclient</artifactId>
-			<version>4.5.9</version>
+			<version>4.5.14</version>
 			<scope>test</scope>
 		</dependency>
 	</dependencies>
@@ -104,7 +113,7 @@
 		<plugins>
 			<plugin>
 				<artifactId>maven-surefire-plugin</artifactId>
-				<version>3.0.0-M5</version>
+				<version>3.4.0</version>
 				<dependencies>
 					<dependency>
 						<groupId>org.junit.jupiter</groupId>
@@ -115,7 +124,7 @@
 			</plugin>
 			<plugin>
 				<artifactId>maven-failsafe-plugin</artifactId>
-				<version>3.0.0-M5</version>
+				<version>3.4.0</version>
 				<dependencies>
 					<dependency>
 						<groupId>org.junit.jupiter</groupId>
@@ -124,29 +133,6 @@
 					</dependency>
 				</dependencies>
 			</plugin>
-			<plugin>
-				<artifactId>maven-source-plugin</artifactId>
-				<executions>
-					<execution>
-						<id>source</id>
-						<phase>package</phase>
-						<goals><goal>jar-no-fork</goal></goals>
-					</execution>
-				</executions>
-			</plugin>
-			<plugin>
-				<artifactId>maven-javadoc-plugin</artifactId>
-				<executions>
-					<execution>
-						<id>javadoc</id>
-						<phase>package</phase>
-						<goals><goal>jar</goal></goals>
-						<configuration>
-							<show>public</show>
-						</configuration>
-					</execution>
-				</executions>
-			</plugin>
 		</plugins>
 	</build>
 
@@ -158,6 +144,29 @@
 			</properties>
 			<build>
 				<plugins>
+					<plugin>
+						<artifactId>maven-source-plugin</artifactId>
+						<executions>
+							<execution>
+								<id>source</id>
+								<phase>package</phase>
+								<goals><goal>jar-no-fork</goal></goals>
+							</execution>
+						</executions>
+					</plugin>
+					<plugin>
+						<artifactId>maven-javadoc-plugin</artifactId>
+						<executions>
+							<execution>
+								<id>javadoc</id>
+								<phase>package</phase>
+								<goals><goal>jar</goal></goals>
+								<configuration>
+									<show>public</show>
+								</configuration>
+							</execution>
+						</executions>
+					</plugin>
 					<plugin>
 						<artifactId>maven-gpg-plugin</artifactId>
 						<executions>
@@ -171,7 +180,7 @@
 					<plugin>
 						<groupId>org.sonatype.plugins</groupId>
 						<artifactId>nexus-staging-maven-plugin</artifactId>
-						<version>1.6.13</version>
+						<version>1.6.14</version>
 						<configuration>
 							<serverId>ossrh</serverId>
 							<nexusUrl>https://s01.oss.sonatype.org/</nexusUrl>

src/main/java/com/inteligr8/rs/AuthorizationFilter.java

@@ -14,7 +14,7 @@
  */
 package com.inteligr8.rs;
 
-import javax.ws.rs.client.ClientRequestFilter;
+import jakarta.ws.rs.client.ClientRequestFilter;
 
 /**
  * This is a marker that allows the developer to segregate, restrict, or limit

src/main/java/com/inteligr8/rs/BasicAuthorizationFilter.java

@@ -17,8 +17,10 @@ package com.inteligr8.rs;
 import java.io.UnsupportedEncodingException;
 import java.util.Base64;
 
-import javax.ws.rs.client.ClientRequestContext;
-import javax.ws.rs.core.HttpHeaders;
+import jakarta.ws.rs.client.ClientRequestContext;
+import jakarta.ws.rs.core.HttpHeaders;
+
+import org.apache.commons.lang3.StringUtils;
 
 /**
  * This class implements a simple 2-credential (username & password) based
@@ -32,12 +34,14 @@ public class BasicAuthorizationFilter implements AuthorizationFilter {
 	private final String password;
 	
 	/**
+	 * This constructor instantiates the filter with required fields.
+	 * 
 	 * @param username A username or access key.
 	 * @param password A password or secret key.
 	 */
 	public BasicAuthorizationFilter(String username, String password) {
-		this.username = username;
-		this.password = password;
+		this.username = StringUtils.trimToNull(username);
+		this.password = StringUtils.trimToNull(password);
 	}
 	
 	/**

src/main/java/com/inteligr8/rs/BearerTokenAuthorizationFilter.java

@@ -14,8 +14,8 @@
  */
 package com.inteligr8.rs;
 
-import javax.ws.rs.client.ClientRequestContext;
-import javax.ws.rs.core.HttpHeaders;
+import jakarta.ws.rs.client.ClientRequestContext;
+import jakarta.ws.rs.core.HttpHeaders;
 
 /**
  * This class implements a simple long living or proxied token-based
@@ -32,6 +32,8 @@ public class BearerTokenAuthorizationFilter implements AuthorizationFilter {
 	private final String token;
 	
 	/**
+	 * This constructor instantiates the filter with required fields.
+	 * 
 	 * @param token A 'Bearer' token.
 	 */
 	public BearerTokenAuthorizationFilter(String token) {

src/main/java/com/inteligr8/rs/Client.java

@@ -14,33 +14,41 @@
  */
 package com.inteligr8.rs;
 
-import javax.ws.rs.client.ClientBuilder;
-import javax.ws.rs.client.WebTarget;
+import java.util.concurrent.TimeUnit;
+
+import jakarta.ws.rs.client.ClientBuilder;
+import jakarta.ws.rs.client.WebTarget;
 
 import com.fasterxml.jackson.databind.DeserializationFeature;
+import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.SerializationFeature;
-import com.fasterxml.jackson.jaxrs.json.JacksonJaxbJsonProvider;
-import com.fasterxml.jackson.jaxrs.json.JacksonJsonProvider;
+import com.fasterxml.jackson.datatype.jsr310.JavaTimeModule;
+import com.fasterxml.jackson.jakarta.rs.json.JacksonJsonProvider;
 
 /**
- * A class that provides pre-configured JAX-RS Client & WebTarget objects.
+ * A class that provides pre-configured Jakarta RS Client & WebTarget objects.
  * 
  * @author brian@inteligr8.com
  */
 public abstract class Client {
 	
 	private final Object sync = new Object();
-	private javax.ws.rs.client.Client client;
+	private jakarta.ws.rs.client.Client client;
 	
 	/**
+	 * This method retrieves the configuration for the client.
+	 * 
 	 * @return The client configuration.
 	 */
 	public abstract ClientConfiguration getConfig();
 	
 	/**
-	 * @return A pre-configured JAX-RS client (no URL) with configured authorization.
+	 * This method retrieves an anonymous cached instance of the underlying
+	 * Jakarta RS client.
+	 * 
+	 * @return A pre-configured Jakarta RS client (no URL) with configured authorization.
 	 */
-	public final javax.ws.rs.client.Client getClient() {
+	public final jakarta.ws.rs.client.Client getClient() {
 		synchronized (this.sync) {
 			if (this.client == null)
 				this.client = this.buildClient((AuthorizationFilter)null);
@@ -50,10 +58,13 @@ public abstract class Client {
 	}
 	
 	/**
+	 * This method retrieves either an anonymous cached instance or builds an
+	 * authorized instance of the underlying Jakarta RS client.
+	 * 
 	 * @param authFilter A dynamic authorization filter.
-	 * @return A pre-configured JAX-RS client (no URL) with the specified authorization.
+	 * @return A pre-configured Jakarta RS client (no URL) with the specified authorization.
 	 */
-	public javax.ws.rs.client.Client getClient(AuthorizationFilter authFilter) {
+	public jakarta.ws.rs.client.Client getClient(AuthorizationFilter authFilter) {
 		if (authFilter == null) {
 			return this.getClient();
 		} else {
@@ -62,12 +73,19 @@ public abstract class Client {
 	}
 	
 	/**
+	 * This method builds a new Jakarta RS client with optional authorization.
+	 * 
 	 * @param authFilter A dynamic authorization filter.
-	 * @return A pre-configured JAX-RS client (no URL) with the specified authorization.
+	 * @return A pre-configured Jakarta RS client (no URL) with the specified authorization.
 	 */
-	public final javax.ws.rs.client.Client buildClient(AuthorizationFilter authFilter) {
-		JacksonJsonProvider provider = new JacksonJaxbJsonProvider();
-
+	public final jakarta.ws.rs.client.Client buildClient(AuthorizationFilter authFilter) {
+	    ObjectMapper om = new ObjectMapper();
+	    om.registerModules(new JavaTimeModule());
+	    this.getConfig().configureJacksonMapper(om);
+	    
+	    JacksonJsonProvider provider = new JacksonJsonProvider(om, JacksonJsonProvider.BASIC_ANNOTATIONS);
+		this.getConfig().configureJacksonProvider(provider);
+        
 		if (this.getConfig().isWrapRootValueEnabled())
 			provider.enable(SerializationFeature.WRAP_ROOT_VALUE);
 		if (this.getConfig().isUnwrapRootValueEnabled())
@@ -76,25 +94,36 @@ public abstract class Client {
 		ClientBuilder clientBuilder = ClientBuilder.newBuilder()
 				.register(provider)
 				.register(new LoggingFilter());
+		
+		if (this.getConfig().getConnectTimeoutInMillis() != null)
+		    clientBuilder.connectTimeout(this.getConfig().getConnectTimeoutInMillis(), TimeUnit.MILLISECONDS);
+        if (this.getConfig().getResponseTimeoutInMillis() != null)
+            clientBuilder.readTimeout(this.getConfig().getResponseTimeoutInMillis(), TimeUnit.MILLISECONDS);
 
 		if (authFilter == null)
 			authFilter = this.getConfig().createAuthorizationFilter();
 		if (authFilter != null)
 			clientBuilder.register(authFilter);
 		this.buildClient(clientBuilder);
+		this.getConfig().configureClient(clientBuilder);
 		
 		return clientBuilder.build();
 	}
-	
-	/**
-	 * @param clientBuilder A client builder
-	 */
-	public void buildClient(ClientBuilder clientBuilder) {
-		// for extension purposes
-	}
+    
+    /**
+	 * This method allows sub-classes to extend the Jakarta RS client builder
+	 * before the client is built.
+	 * 
+     * @param clientBuilder A Jakarta RS client builder.
+     */
+    public void buildClient(ClientBuilder clientBuilder) {
+        // for extension purposes
+    }
 
 	/**
-	 * @return A pre-configured JAX-RS target (client w/ base URL) with configured authorization.
+	 * This method builds an anonymous Jakarta RS target.
+	 * 
+	 * @return A pre-configured Jakarta RS target (client w/ base URL) with configured authorization.
 	 */
 	public final WebTarget getTarget() {
 		return this.getClient()
@@ -102,8 +131,10 @@ public abstract class Client {
 	}
 
 	/**
+	 * This method builds an authorized Jakarta RS target.
+	 * 
 	 * @param authFilter A dynamic authorization filter.
-	 * @return A pre-configured JAX-RS target (client w/ base URL) with the specified authorization.
+	 * @return A pre-configured Jakarta RS target (client w/ base URL) with the specified authorization.
 	 */
 	public WebTarget getTarget(AuthorizationFilter authFilter) {
 		if (authFilter == null) {
@@ -115,10 +146,10 @@ public abstract class Client {
 	}
 	
 	/**
-	 * This method retrieves a JAX-RS implementation of the specified API.
+	 * This method retrieves a Jakarta RS implementation of the specified API.
 	 * 
-	 * @param <T> A JAX-RS annotated API class.
-	 * @param apiClass A JAX-RS annotated API class.
+	 * @param <T> A Jakarta RS annotated API class.
+	 * @param apiClass A Jakarta RS annotated API class.
 	 * @return An instance of the API class.
 	 */
 	public final <T> T getApi(Class<T> apiClass) {
@@ -126,12 +157,12 @@ public abstract class Client {
 	}
 
 	/**
-	 * This method retrieves a JAX-RS implementation of the specified API with
+	 * This method retrieves a Jakarta RS implementation of the specified API with
 	 * the specified authorization.
 	 * 
-	 * @param <T> A JAX-RS annotated API class.
+	 * @param <T> A Jakarta RS annotated API class.
 	 * @param authFilter A dynamic authorization filter.
-	 * @param apiClass A JAX-RS annotated API class.
+	 * @param apiClass A Jakarta RS annotated API class.
 	 * @return An instance of the API class.
 	 */
 	public abstract <T> T getApi(AuthorizationFilter authFilter, Class<T> apiClass);

src/main/java/com/inteligr8/rs/ClientConfiguration.java

@@ -16,6 +16,11 @@ package com.inteligr8.rs;
 
 import java.net.URI;
 
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.jakarta.rs.json.JacksonJsonProvider;
+
+import jakarta.ws.rs.client.ClientBuilder;
+
 /**
  * This interface defines the configurable parameters of the clients; primarily
  * their default authentication and authorization.
@@ -25,109 +30,190 @@ import java.net.URI;
 public interface ClientConfiguration {
 	
 	/**
-	 * @return The base or root URL of the service.
+	 * This method retrieves the base/root URL of the client service.
+	 * 
+	 * @return The URL.
 	 */
 	String getBaseUrl();
 	
 	/**
-	 * @return The username for BASIC authentication.
+	 * This method retrieves the username to use in HTTP BASIC authentication/authorization.
+	 * 
+	 * @return A username.
 	 */
 	default String getBasicAuthUsername() {
 		return null;
 	}
 
 	/**
-	 * @return The corresponding password for the username in BASIC authentication.
+	 * This method retrieves the password to use in HTTP BASIC authentication/authorization.
+	 * 
+	 * @return The corresponding password for the username.
 	 */
 	default String getBasicAuthPassword() {
 		return null;
 	}
 	
 	/**
-	 * @return The client ID for Client Enforcement authentication.
+	 * This method retrieves the client identifier to use in Client Enforcement authorization.
+	 * 
+	 * @return A client identifier.
 	 */
 	default String getClientId() {
 		return null;
 	}
 
 	/**
-	 * @return The corresponding client secret for the client ID in Client Enforcement authentication.
+	 * This method retrieves the client secret to use in Client Enforcement authorization.
+	 * 
+	 * @return The corresponding client secret for the client identifier.
 	 */
 	default String getClientSecret() {
 		return null;
 	}
 	
 	/**
-	 * @return The token for BEARER authorization.
+	 * This method retrieves the token to use in HTTP BEARER authorization.
+	 * This is provided in a response to the token URL.
+	 * 
+	 * @return An access token.
 	 */
 	default String getBearerToken() {
 		return null;
 	}
 	
 	/**
-	 * @return The token URL for OAuth authorization.
+	 * This method retrieves the token URL to use for OAuth authorization.
+	 * The value can be pulled from OAuth endpoint well-known meta-data.  That
+	 * endpoint or the token URL itself may also be provided OAuth IdP
+	 * administrator.
+	 * 
+	 * @return An OAuth token URL.
 	 */
 	default String getOAuthTokenUrl() {
 		return null;
 	}
 	
 	/**
-	 * @return The client ID provided by the OAuth IdP administrator.
+	 * This method retrieves the client identifier to use in OAuth
+	 * authorization.  This is provided by the OAuth IdP administrator or
+	 * tooling.
+	 * 
+	 * @return A client identifier.
 	 */
 	default String getOAuthClientId() {
 		return this.getClientId();
 	}
 
 	/**
-	 * @return The corresponding client secret for the client ID provided by the OAuth IdP administrator.
+	 * This method retrieves the client secret to use in OAuth authorization.
+	 * This is provided by the OAuth IdP administrator or tooling.
+	 * 
+	 * @return The corresponding client secret for the client identifier.
 	 */
 	default String getOAuthClientSecret() {
 		return this.getClientSecret();
 	}
 	
 	/**
-	 * @return The authorization code used in the OAuth Authorization Code flow.
+	 * This method retrieves the authorization code to use in OAuth
+	 * Authorization Code flow.  This is provided by the OAuth IdP
+	 * administrator or tooling.
+	 * 
+	 * @return An authorization code.
 	 */
 	default String getOAuthAuthCode() {
 		return null;
 	}
 	
 	/**
-	 * @return The redirect URL used in the OAuth Authorization Code flow.
+	 * This method retrieves the redirect URL to use in OAuth Authorization
+	 * Code flow.  This has meaning to the client-side web application.
+	 * 
+	 * @return A URL for the OAuth flow to redirect to when complete.
 	 */
 	default String getOAuthAuthRedirectUri() {
 		return null;
 	}
 	
 	/**
-	 * @return The username used in the OAuth Password Grant flow.
+	 * This method retrieves the username to use in OAuth Password Grant flow.
+	 * This is provided by the OAuth IdP administrator or tooling.
+	 * 
+	 * @return A username.
 	 */
 	default String getOAuthUsername() {
 		return null;
 	}
 	
 	/**
-	 * @return The corresponding password for the username used in the OAuth Password Grant flow.
+	 * This method retrieves the password to use in OAuth Password Grant flow.
+	 * This is provided by the OAuth IdP administrator or tooling.
+	 * 
+	 * @return The corresponding password for the username.
 	 */
 	default String getOAuthPassword() {
 		return null;
 	}
 	
 	
+	
+	/**
+	 * This method retrieves the connection (before request sent) timeout for
+	 * the client.
+	 * 
+	 * @return A timeout in milliseconds.
+	 */
+	default Integer getConnectTimeoutInMillis() {
+	    return null;
+	}
+	
+	/**
+	 * This method retrieves the response (after request sent) timeout for the
+	 * client.
+	 * 
+	 * @return A timeout in milliseconds.
+	 */
+	default Integer getResponseTimeoutInMillis() {
+	    return null;
+	}
+	
+	
 
 	/**
-	 * @return true to enable Jackson UNWRAP_ROOT_VALUE feature; false otherwise.
+	 * This method enables/disables the JackSON UNWRAP_ROOT_VALUE feature.
+	 * 
+	 * @return `true` to enable; `false` otherwise.
 	 */
 	default boolean isUnwrapRootValueEnabled() {
 		return false;
 	}
 
 	/**
-	 * @return true to enable Jackson WRAP_ROOT_VALUE feature; false otherwise.
+	 * This method enables/disables the JackSON WRAP_ROOT_VALUE feature.
+	 * 
+	 * @return `true` to enable; `false` otherwise.
 	 */
 	default boolean isWrapRootValueEnabled() {
 		return false;
 	}
+    
+    /**
+	 * This method allows sub-classes to extend the JackSON mapper
+	 * configuration and behavior.
+	 * 
+     * @param mapper A JackSON object mapper.
+     */
+    default void configureJacksonMapper(ObjectMapper mapper) {
+    }
+	
+	/**
+	 * This method allows sub-classes to extend the JackSON JSON provider.
+	 * 
+	 * @param provider A JackSON Jakarta RS provider.
+	 */
+	default void configureJacksonProvider(JacksonJsonProvider provider) {
+	}
 	
 	
 
@@ -169,5 +255,13 @@ public interface ClientConfiguration {
 			return null;
 		}
 	}
+    
+    /**
+     * A Jackson provider, logging filter, and authentication filter are already registered.
+     * 
+     * @param clientBuilder A JAX-RS client builder to configure.
+     */
+    default void configureClient(ClientBuilder clientBuilder) {
+    }
 
 }

src/main/java/com/inteligr8/rs/ClientEnforcementAuthorizationFilter.java

@@ -14,7 +14,9 @@
  */
 package com.inteligr8.rs;
 
-import javax.ws.rs.client.ClientRequestContext;
+import jakarta.ws.rs.client.ClientRequestContext;
+
+import org.apache.commons.lang3.StringUtils;
 
 /**
  * This class is the base for implementations of client authorization similar
@@ -45,8 +47,8 @@ public class ClientEnforcementAuthorizationFilter implements AuthorizationFilter
 	 * @param clientSecret A secret corresponding to the client ID.
 	 */
 	public ClientEnforcementAuthorizationFilter(String clientId, String clientSecret) {
-		this.clientId = clientId;
-		this.clientSecret = clientSecret;
+		this.clientId = StringUtils.trimToNull(clientId);
+		this.clientSecret = StringUtils.trimToNull(clientSecret);
 	}
 
 	/**

src/main/java/com/inteligr8/rs/ClientImpl.java

@@ -0,0 +1,66 @@
+/*
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.inteligr8.rs;
+
+import jakarta.annotation.PostConstruct;
+import jakarta.ws.rs.client.ClientBuilder;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * A class that provides pre-configured Jakarta RS Client &amp; WebTarget
+ * objects.
+ * 
+ * @author brian@inteligr8.com
+ */
+public class ClientImpl extends Client {
+	
+	private final Logger logger = LoggerFactory.getLogger(ClientImpl.class);
+	
+	private ClientConfiguration config;
+	
+	/**
+	 * This constructor is for Spring or POJO use.
+	 * 
+	 * @param config The client configuration.
+	 */
+	public ClientImpl(ClientConfiguration config) {
+		this.config = config;
+	}
+
+	/**
+	 * This method is a placeholder.
+	 */
+	@PostConstruct
+	public void register() {
+		this.logger.info("API Base URL: {}", this.getConfig().getBaseUrl());
+	}
+	
+	@Override
+	public void buildClient(ClientBuilder clientBuilder) {
+	}
+	
+	@Override
+	public ClientConfiguration getConfig() {
+		return this.config;
+	}
+
+	@Override
+	public <T> T getApi(AuthorizationFilter authFilter, Class<T> apiClass) {
+		throw new UnsupportedOperationException();
+	}
+
+}

src/main/java/com/inteligr8/rs/ForwardingAuthorizationFilter.java

@@ -14,8 +14,8 @@
  */
 package com.inteligr8.rs;
 
-import javax.ws.rs.client.ClientRequestContext;
-import javax.ws.rs.core.HttpHeaders;
+import jakarta.ws.rs.client.ClientRequestContext;
+import jakarta.ws.rs.core.HttpHeaders;
 
 /**
  * This class implements a proxied or forwarded authorization header based
@@ -32,6 +32,8 @@ public class ForwardingAuthorizationFilter implements AuthorizationFilter {
 	private final String authorizationHeaderValue;
 	
 	/**
+	 * This constructor instantiates the filter with required fields.
+	 * 
 	 * @param authorizationHeaderValue A previously used or formulated 'Authorization' header.
 	 */
 	public ForwardingAuthorizationFilter(String authorizationHeaderValue) {

src/main/java/com/inteligr8/rs/HeaderAuthorizationFilter.java

@@ -0,0 +1,68 @@
+/*
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.inteligr8.rs;
+
+import java.io.UnsupportedEncodingException;
+import java.util.List;
+import java.util.Map.Entry;
+
+import org.springframework.util.LinkedMultiValueMap;
+import org.springframework.util.MultiValueMap;
+
+import jakarta.ws.rs.client.ClientRequestContext;
+
+/**
+ * This class implements a header-based authorization filter.
+ *  
+ * @author brian@inteligr8.com
+ */
+public class HeaderAuthorizationFilter implements AuthorizationFilter {
+	
+	private final MultiValueMap<String, Object> headers = new LinkedMultiValueMap<>();
+	
+	/**
+	 * This constructor instantiates the filter with required fields.
+	 * 
+	 * @param headerName A header name.
+	 * @param headerValue A header value.
+	 */
+    public HeaderAuthorizationFilter(String headerName, Object headerValue) {
+	    this.headers.add(headerName, headerValue);
+	}
+    
+	/**
+	 * This method adds another header name/value to outgoing requests.
+	 * 
+	 * @param headerName A header name.
+	 * @param headerValue A header value.
+	 * @return This class for fluent chaining.
+	 */
+    public HeaderAuthorizationFilter add(String headerName, Object headerValue) {
+        this.headers.add(headerName, headerValue);
+        return this;
+    }
+	
+	/**
+	 * This method applies the 'Authorization' header to the {@link ClientRequestContext}.
+	 * 
+	 * @param requestContext A request context.
+	 */
+	@Override
+	public void filter(ClientRequestContext requestContext) throws UnsupportedEncodingException {
+	    for (Entry<String, List<Object>> header : this.headers.entrySet())
+	        requestContext.getHeaders().put(header.getKey(), header.getValue());
+	}
+
+}

src/main/java/com/inteligr8/rs/LoggingFilter.java

@@ -16,12 +16,12 @@ package com.inteligr8.rs;
 
 import java.io.IOException;
 
-import javax.ws.rs.client.ClientRequestContext;
-import javax.ws.rs.client.ClientRequestFilter;
-import javax.ws.rs.client.ClientResponseContext;
-import javax.ws.rs.client.ClientResponseFilter;
-import javax.ws.rs.core.Form;
-import javax.ws.rs.core.MediaType;
+import jakarta.ws.rs.client.ClientRequestContext;
+import jakarta.ws.rs.client.ClientRequestFilter;
+import jakarta.ws.rs.client.ClientResponseContext;
+import jakarta.ws.rs.client.ClientResponseFilter;
+import jakarta.ws.rs.core.Form;
+import jakarta.ws.rs.core.MediaType;
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -58,7 +58,7 @@ public class LoggingFilter implements ClientRequestFilter, ClientResponseFilter
 				logger.trace("request: {} {}: {}", requestContext.getMethod(), requestContext.getUri(),
 						((Form)requestContext.getEntity()).asMap());
 			} else {
-				this.loggerRequest.trace("request: {} {}: failed to output form", requestContext.getMethod(), requestContext.getUri());
+				logger.trace("request: {} {}: failed to output form", requestContext.getMethod(), requestContext.getUri());
 			}
 		} else {
 			this.logUnhandledRequest(requestContext, logger);

src/main/java/com/inteligr8/rs/OAuthAuthorizationCodeAuthorizationFilter.java

@@ -16,7 +16,11 @@ package com.inteligr8.rs;
 
 import java.net.URI;
 
-import javax.ws.rs.core.Form;
+import jakarta.ws.rs.core.Form;
+
+import org.apache.commons.lang3.StringUtils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 /**
  * This class implements the OAuth Authorization Code flow as an authorization
@@ -25,6 +29,8 @@ import javax.ws.rs.core.Form;
  * @author brian@inteligr8.com
  */
 public class OAuthAuthorizationCodeAuthorizationFilter extends OAuthAuthorizationFilter {
+    
+    private final Logger logger = LoggerFactory.getLogger(this.getClass());
 	
 	private final String code;
 	private final URI redirectUri;
@@ -68,17 +74,22 @@ public class OAuthAuthorizationCodeAuthorizationFilter extends OAuthAuthorizatio
 	public OAuthAuthorizationCodeAuthorizationFilter(String tokenUrl, String clientId, String clientSecret, String code, URI redirectUri) {
 		super(tokenUrl, clientId, clientSecret);
 		
-		this.code = code;
+		this.code = StringUtils.trimToNull(code);
 		this.redirectUri = redirectUri;
 	}
 	
 	@Override
 	protected Form createForm() {
-		Form form = new Form().param("grant_type", "authorization_code")
-				.param("code", this.code);
+        this.logger.debug("Using OAuth grant_type 'authorization_code'");
+		Form form = new Form().param("grant_type", "authorization_code");
 		if (this.redirectUri != null)
 			form.param("redirect_uri", this.redirectUri.toString());
 		return form;
 	}
+	
+	@Override
+	protected void extendFormSensitive(Form form) {
+	    form.param("code", this.code);
+	}
 
 }

src/main/java/com/inteligr8/rs/OAuthAuthorizationFilter.java

@@ -16,15 +16,22 @@ package com.inteligr8.rs;
 
 import java.util.Map;
 
-import javax.ws.rs.WebApplicationException;
-import javax.ws.rs.client.ClientBuilder;
-import javax.ws.rs.client.ClientRequestContext;
-import javax.ws.rs.client.Entity;
-import javax.ws.rs.client.WebTarget;
-import javax.ws.rs.core.Form;
-import javax.ws.rs.core.HttpHeaders;
+import jakarta.ws.rs.WebApplicationException;
+import jakarta.ws.rs.client.Client;
+import jakarta.ws.rs.client.ClientBuilder;
+import jakarta.ws.rs.client.ClientRequestContext;
+import jakarta.ws.rs.client.Entity;
+import jakarta.ws.rs.client.WebTarget;
+import jakarta.ws.rs.core.Form;
+import jakarta.ws.rs.core.HttpHeaders;
+import jakarta.ws.rs.core.Response;
+import jakarta.ws.rs.core.Response.Status.Family;
 
-import com.fasterxml.jackson.jaxrs.json.JacksonJaxbJsonProvider;
+import org.apache.commons.lang3.StringUtils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import com.fasterxml.jackson.jakarta.rs.json.JacksonJsonProvider;
 
 /**
  * This class is the base for implementations of OAuth authorization flows.
@@ -33,6 +40,8 @@ import com.fasterxml.jackson.jaxrs.json.JacksonJaxbJsonProvider;
  */
 public abstract class OAuthAuthorizationFilter implements AuthorizationFilter {
 	
+    private final Logger logger = LoggerFactory.getLogger(this.getClass());
+    
 	private final String tokenUrl;
 	private final String clientId;
 	private final String clientSecret;
@@ -40,6 +49,7 @@ public abstract class OAuthAuthorizationFilter implements AuthorizationFilter {
 	private String accessToken;
 	private long expiration;
 	private String refreshToken;
+	private Long refreshTokenExpiration;
 	
 	/**
 	 * This constructor creates an OAuth-based authorization filter using the
@@ -79,9 +89,9 @@ public abstract class OAuthAuthorizationFilter implements AuthorizationFilter {
 	 */
 	public OAuthAuthorizationFilter(String tokenUrl, String clientId, String clientSecret, String scope) {
 		this.tokenUrl = tokenUrl;
-		this.clientId = clientId;
-		this.clientSecret = clientSecret;
-		this.scope = scope;
+		this.clientId = StringUtils.trimToNull(clientId);
+		this.clientSecret = StringUtils.trimToNull(clientSecret);
+		this.scope = StringUtils.trimToNull(scope);
 	}
 
 	/**
@@ -91,8 +101,29 @@ public abstract class OAuthAuthorizationFilter implements AuthorizationFilter {
 	 */
 	@Override
 	public void filter(ClientRequestContext requestContext) {
-		if (this.accessToken == null || System.currentTimeMillis() > this.expiration)
-			this.requestToken();
+		if (this.accessToken == null) {
+		    this.requestToken();
+		} else if (System.currentTimeMillis() >= this.expiration) {
+            this.logger.trace("Access token expired; retrieving new one with refresh token");
+            
+		    if (this.refreshTokenExpiration != null && System.currentTimeMillis() >= this.refreshTokenExpiration.longValue()) {
+                this.logger.debug("Refresh token expired; performing full authentication");
+                this.refreshToken = null;
+                this.requestToken();
+		    } else {
+    		    try {
+    		        this.requestToken();
+                } catch (WebApplicationException wae) {
+                    if (wae.getResponse().getStatusInfo().getFamily() == Family.CLIENT_ERROR) {
+                        this.logger.debug("Received OAuth response {} using refresh token; performing full authentication", wae.getResponse().getStatus());
+                        this.refreshToken = null;
+                        this.requestToken();
+                    } else {
+                        throw wae;
+                    }
+                }
+		    }
+		}
 		
 		requestContext.getHeaders().add(HttpHeaders.AUTHORIZATION, "Bearer " + this.accessToken);
 	}
@@ -111,29 +142,53 @@ public abstract class OAuthAuthorizationFilter implements AuthorizationFilter {
 		}
 
 		form.param("client_id", this.clientId);
-		if (this.clientSecret != null)
-			form.param("client_secret", this.clientSecret);
 		if (this.scope != null)
 			form.param("scope", this.scope);
-		this.extendRefreshTokenForm(form);
+		
+		this.logger.trace("Sending OAuth request: {}", form);
+		
+		if (this.refreshToken != null) {
+		    this.extendRefreshFormSensitive(form);
+		} else {
+            this.extendFormSensitive(form);
+		}
+
+        if (this.clientSecret != null)
+            form.param("client_secret", this.clientSecret);
 		
 		Entity<Form> entity = Entity.form(form);
 		
-		WebTarget target = ClientBuilder.newBuilder()
-				.register(new JacksonJaxbJsonProvider())
-				.build()
-				.target(this.tokenUrl);
+		Client client = ClientBuilder.newBuilder()
+                .register(new JacksonJsonProvider())
+                .build();
+		WebTarget target = client.target(this.tokenUrl);
+		
+		long requestSendTime = System.currentTimeMillis();
 
-		@SuppressWarnings("unchecked")
-		Map<String, Object> response = target.request().post(entity, Map.class);
+		Response response = target.request().post(entity);
 		
-		if (response.containsKey("error"))
-			throw new WebApplicationException((String)response.get("error"), 400);
+        this.logger.debug("Received OAuth response: {}", response.getStatus());
+
+        @SuppressWarnings("unchecked")
+        Map<String, Object> responseMap = response.readEntity(Map.class);
+
+        this.logger.trace("Received OAuth response: {}", responseMap);
 		
-		this.accessToken = (String)response.get("access_token");
-		this.expiration = System.currentTimeMillis() + ((Number)response.get("expires_in")).longValue() * 1000L;
-		this.refreshToken = (String)response.get("refresh_token");
-		this.extendRefreshTokenResponse(response);
+		if (response.getStatusInfo().getFamily() != Family.SUCCESSFUL) {
+            String code = (String) responseMap.get("error");
+            if (code != null) {
+                String description = (String) responseMap.get("error_description");
+    			throw new WebApplicationException(code + ": " + description, response.getStatus());
+            } else {
+                throw new WebApplicationException(response);
+            }
+		}
+		
+		this.accessToken = (String)responseMap.get("access_token");
+		this.expiration = requestSendTime + ((Number)responseMap.get("expires_in")).longValue() * 1000L;
+		this.refreshToken = (String)responseMap.get("refresh_token");
+		if (responseMap.containsKey("refresh_token_expires_in"))
+		    this.refreshTokenExpiration = requestSendTime + ((Number)responseMap.get("refresh_token_expires_in")).longValue() * 1000L;
 	}
 	
 	protected Form createRefreshForm() {
@@ -143,10 +198,9 @@ public abstract class OAuthAuthorizationFilter implements AuthorizationFilter {
 	
 	protected abstract Form createForm();
 	
-	protected void extendRefreshTokenForm(Form form) {
-	}
-	
-	protected void extendRefreshTokenResponse(Map<String, Object> response) {
+	protected void extendRefreshFormSensitive(Form form) {
 	}
 
+    protected abstract void extendFormSensitive(Form form);
+
 }

src/main/java/com/inteligr8/rs/OAuthClientCredentialAuthorizationFilter.java

@@ -14,7 +14,10 @@
  */
 package com.inteligr8.rs;
 
-import javax.ws.rs.core.Form;
+import jakarta.ws.rs.core.Form;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 /**
  * This class implements the OAuth Client Credential flow as an authorization
@@ -23,6 +26,8 @@ import javax.ws.rs.core.Form;
  * @author brian@inteligr8.com
  */
 public class OAuthClientCredentialAuthorizationFilter extends OAuthAuthorizationFilter {
+    
+    private final Logger logger = LoggerFactory.getLogger(this.getClass());
 
 	/**
 	 * @param tokenUrl The URL to the OAuth IdP token service.
@@ -35,7 +40,12 @@ public class OAuthClientCredentialAuthorizationFilter extends OAuthAuthorization
 	
 	@Override
 	protected Form createForm() {
+        this.logger.debug("Using OAuth grant_type 'client_credentials'");
 		return new Form().param("grant_type", "client_credentials");
 	}
+	
+	@Override
+	protected void extendFormSensitive(Form form) {
+	}
 
 }

src/main/java/com/inteligr8/rs/OAuthPasswordGrantAuthorizationFilter.java

@@ -14,7 +14,11 @@
  */
 package com.inteligr8.rs;
 
-import javax.ws.rs.core.Form;
+import jakarta.ws.rs.core.Form;
+
+import org.apache.commons.lang3.StringUtils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 /**
  * This class implements the OAuth Password Grant flow as an authorization
@@ -23,6 +27,8 @@ import javax.ws.rs.core.Form;
  * @author brian@inteligr8.com
  */
 public class OAuthPasswordGrantAuthorizationFilter extends OAuthAuthorizationFilter {
+    
+    private final Logger logger = LoggerFactory.getLogger(this.getClass());
 	
 	private final String username;
 	private final String password;
@@ -46,15 +52,20 @@ public class OAuthPasswordGrantAuthorizationFilter extends OAuthAuthorizationFil
 	 */
 	public OAuthPasswordGrantAuthorizationFilter(String tokenUrl, String clientId, String clientSecret, String username, String password) {
 		super(tokenUrl, clientId, clientSecret);
-		this.username = username;
-		this.password = password;
+		this.username = StringUtils.trimToNull(username);
+		this.password = StringUtils.trimToNull(password);
 	}
 	
 	@Override
 	protected Form createForm() {
+        this.logger.debug("Using OAuth grant_type 'password': {}", this.username);
 		return new Form().param("grant_type", "password")
-				.param("username", this.username)
-				.param("password", this.password);
+				.param("username", this.username);
+	}
+	
+	@Override
+	protected void extendFormSensitive(Form form) {
+	    form.param("password", this.password);
 	}
 
 }