#44 - Migrate to use System.Logger rather than SLF4J-API (better support for jlink / module-path)

Author: rbygrave

client/pom.xml

@@ -18,12 +18,6 @@
 
   <dependencies>
 
-    <dependency>
-      <groupId>org.slf4j</groupId>
-      <artifactId>slf4j-api</artifactId>
-      <version>1.7.36</version>
-    </dependency>
-
     <dependency>
       <groupId>com.fasterxml.jackson.core</groupId>
       <artifactId>jackson-databind</artifactId>
@@ -40,6 +34,13 @@
 
     <!-- test dependencies  -->
 
+    <dependency>
+      <groupId>io.avaje</groupId>
+      <artifactId>avaje-slf4j-jpl</artifactId>
+      <version>1.0</version>
+      <scope>test</scope>
+    </dependency>
+
     <dependency>
       <groupId>io.avaje</groupId>
       <artifactId>junit</artifactId>

client/src/main/java/io/avaje/http/client/DHttpApi.java

@@ -1,18 +1,17 @@
 package io.avaje.http.client;
 
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
 import java.util.HashMap;
 import java.util.Map;
 import java.util.ServiceLoader;
 
+import static java.lang.System.Logger.Level.*;
+
 /**
  * Service loads the HttpApiProvider for HttpApi.
  */
 final class DHttpApi {
 
-  private static final Logger log = LoggerFactory.getLogger(DHttpApi.class);
+  private static final System.Logger log = System.getLogger("io.avaje.http.client");
 
   private static final DHttpApi INSTANCE = new DHttpApi();
 
@@ -27,7 +26,7 @@ void init() {
     for (HttpApiProvider apiProvider : ServiceLoader.load(HttpApiProvider.class)) {
       addProvider(apiProvider);
     }
-    log.debug("providers for {}", providerMap.keySet());
+    log.log(DEBUG, "providers for %s", providerMap.keySet());
   }
 
   void addProvider(HttpApiProvider apiProvider) {

client/src/main/java/io/avaje/http/client/RequestLogger.java

@@ -1,8 +1,6 @@
 package io.avaje.http.client;
 
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
+import java.lang.System.Logger.Level;
 import java.net.http.HttpHeaders;
 import java.net.http.HttpRequest;
 import java.net.http.HttpResponse;
@@ -11,23 +9,24 @@
 import java.util.Set;
 
 /**
- * Logs request and response details for debug logging purposes.
+ * Logs request and response details for debug logging purposes using <code>System.Logger</code>.
+ * <p>
+ * This implementation logs the request and response with the same single logging entry
+ * rather than separate logging of the request and response.
  * <p>
- * This implementation logs the request and response with the same
- * single logging entry rather than separate logging of the request
- * and response.
+ * With logging level set to {@code DEBUG} for {@code io.avaje.http.client.RequestLogger} the
+ * request and response are logged as a summary with response status and time.
  * <p>
- * With logging level set to {@code DEBUG} for
- * {@code io.avaje.http.client.RequestLogger} the request and response
- * are logged as a summary with response status and time.
+ * Set the logging level to {@code TRACE} to include the request and response headers and body
+ * payloads with truncation for large bodies.
  * <p>
- * Set the logging level to {@code TRACE} to include the request
- * and response headers and body payloads with truncation for large
- * bodies.
+ * Using System.Logger, messages by default go to JUL (Java Util Logging) unless a provider
+ * is registered. We can use <em>io.avaje:avaje-slf4j-jpl</em> to have System.Logger
+ * messages go to <em>slf4j-api</em>.
  */
 public class RequestLogger implements RequestListener {
 
-  private static final Logger log = LoggerFactory.getLogger(RequestLogger.class);
+  private static final System.Logger log = System.getLogger("io.avaje.http.client.RequestLogger");
 
   private final String delimiter;
 
@@ -47,7 +46,7 @@ public RequestLogger(String delimiter) {
 
   @Override
   public void response(Event event) {
-    if (log.isDebugEnabled()) {
+    if (log.isLoggable(Level.DEBUG)) {
       final HttpResponse<?> response = event.response();
       final HttpRequest request = response.request();
       long micros = event.responseTimeMicros();
@@ -58,13 +57,13 @@ public void response(Event event) {
         .append(" uri:").append(event.uri())
         .append(" timeMicros:").append(micros);
 
-      if (log.isTraceEnabled()) {
+      if (log.isLoggable(Level.TRACE)) {
         headers(sb, "req-head: ", request.headers());
         body(sb, "req-body: ", event.requestBody());
         headers(sb, "res-head: ", response.headers());
         body(sb, "res-body: ", event.responseBody());
       }
-      log.debug(sb.toString());
+      log.log(Level.DEBUG, sb.toString());
     }
   }
 

client/src/main/java/io/avaje/http/client/SimpleRetryHandler.java

@@ -1,8 +1,6 @@
 package io.avaje.http.client;
 
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
+import java.lang.System.Logger.Level;
 import java.net.http.HttpResponse;
 import java.util.Random;
 
@@ -11,7 +9,7 @@
  */
 public class SimpleRetryHandler implements RetryHandler {
 
-  private static final Logger log = LoggerFactory.getLogger(SimpleRetryHandler.class);
+  private static final System.Logger log = System.getLogger("io.avaje.http.client");
 
   private final int maxRetries;
   private final long backoffMillis;
@@ -47,7 +45,9 @@ public boolean isRetry(int retryCount, HttpResponse<?> response) {
     if (response.statusCode() < 500 || retryCount >= maxRetries) {
       return false;
     }
-    log.debug("retry count:{} status:{} uri:{}", retryCount, response.statusCode(), response.uri());
+    if (log.isLoggable(Level.DEBUG)) {
+      log.log(Level.DEBUG, "retry count:%s status:%s uri:%s", retryCount, response.statusCode(), response.uri());
+    }
     try {
       int gitter = gitterMillis < 1 ? 0 : random.nextInt(gitterMillis);
       Thread.sleep(backoffMillis + gitter);

client/src/main/java/module-info.java

@@ -3,7 +3,6 @@
   uses io.avaje.http.client.HttpApiProvider;
 
   requires transitive java.net.http;
-  requires transitive org.slf4j;
   requires static com.fasterxml.jackson.databind;
   requires static com.fasterxml.jackson.annotation;
   requires static com.fasterxml.jackson.core;