Improve performance of Java 11 sender

Author: dheid

README.md

@@ -78,7 +78,18 @@ The Spring Boot Starter now requires Spring Boot 4. The `@NonNull` annotation ha
 Fixed a Java 8 compatibility issue in `JavaxHttpServletWrapper` where `Enumeration.asIterator()` (introduced in
 Java 9) was used to iterate over HTTP header names. It has been replaced with a standard `while` loop.
 
-Dependency updates: Spring Boot 3.4.2 → 4.0.5, Jetty EE10 12.0.16 → 12.1.8, Jetty (javax) 10.0.24 → 10.0.26.
+Zero is now accepted as a valid value for numeric tracking parameters such as `idGoal`, `revenue`, and ecommerce
+fields, where it was previously treated as absent and omitted from requests.
+
+Several performance improvements were made to `Java11Sender`: URL construction no longer uses `String.format`,
+the case-insensitive `User-Agent` header lookup no longer allocates a `TreeMap`, `.trim().isEmpty()` checks were
+replaced with the Java 11 `.isBlank()` method, and debug log statements are now guarded to avoid allocating
+cookie list copies when debug logging is disabled.
+
+Spotless now automatically removes unused imports during the build.
+
+Dependency updates: Spring Boot 3.4.2 → 4.0.5, JUnit Jupiter 5.11.4 → 6.0.3, SLF4J 2.0.16 → 2.0.17,
+Jetty EE10 12.0.16 → 12.1.8, Jetty (javax) 10.0.24 → 10.0.26.
 
 The local testing Docker setup now uses MariaDB 12 and Matomo 5.
 

java11/src/main/java/org/matomo/java/tracking/Java11Sender.java

@@ -14,7 +14,6 @@
 import java.util.Collection;
 import java.util.LinkedHashMap;
 import java.util.Map;
-import java.util.TreeMap;
 import java.util.concurrent.Callable;
 import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.ExecutorService;
@@ -77,7 +76,7 @@ private HttpRequest buildHttpPostRequest(
       if (request.getHeaders() != null && !request.getHeaders().isEmpty()) {
         headers.putAll(request.getHeaders());
       }
-      if (request.getHeaderUserAgent() != null && !request.getHeaderUserAgent().trim().isEmpty()) {
+      if (request.getHeaderUserAgent() != null && !request.getHeaderUserAgent().isBlank()) {
         headerUserAgent = request.getHeaderUserAgent();
       }
       queries.add(queryCreator.createQuery(request, null));
@@ -131,9 +130,7 @@ private HttpRequest buildHttpGetRequest(@NonNull MatomoRequest request) {
         HttpRequest.newBuilder()
             .uri(
                 apiEndpoint.resolve(
-                    String.format(
-                        "%s?%s",
-                        apiEndpoint.getPath(), queryCreator.createQuery(request, authToken))));
+                    apiEndpoint.getPath() + "?" + queryCreator.createQuery(request, authToken)));
     applyTrackerConfiguration(builder);
     setUserAgentHeader(builder, request.getHeaderUserAgent(), request.getHeaders());
     addHeaders(builder, request.getHeaders());
@@ -142,9 +139,11 @@ private HttpRequest buildHttpGetRequest(@NonNull MatomoRequest request) {
 
   private <T> T send(@NonNull HttpRequest httpRequest, @NonNull Callable<T> callable) {
     try {
-      log.debug("Sending request to Matomo: {}", httpRequest);
-      log.debug("Headers: {}", httpRequest.headers());
-      log.debug("Cookies: {}", cookieStore.getCookies());
+      if (log.isDebugEnabled()) {
+        log.debug("Sending request to Matomo: {}", httpRequest);
+        log.debug("Headers: {}", httpRequest.headers());
+        log.debug("Cookies: {}", cookieStore.getCookies());
+      }
       return callable.call();
     } catch (Exception e) {
       if (trackerConfiguration.isLogFailedTracking()) {
@@ -188,15 +187,18 @@ private void setUserAgentHeader(
       HttpRequest.Builder builder,
       @Nullable String headerUserAgent,
       @Nullable Map<String, String> headers) {
-    String userAgentHeader = null;
-    if ((headerUserAgent == null || headerUserAgent.trim().isEmpty()) && headers != null) {
-      TreeMap<String, String> caseInsensitiveMap = new TreeMap<>(String.CASE_INSENSITIVE_ORDER);
-      caseInsensitiveMap.putAll(headers);
-      userAgentHeader = caseInsensitiveMap.get("User-Agent");
+    boolean noExplicitUserAgent = headerUserAgent == null || headerUserAgent.isBlank();
+    if (!noExplicitUserAgent) {
+      return;
+    }
+    if (headers != null) {
+      for (Map.Entry<String, String> entry : headers.entrySet()) {
+        if ("User-Agent".equalsIgnoreCase(entry.getKey()) && entry.getValue() != null && !entry.getValue().isBlank()) {
+          return;
+        }
+      }
     }
-    if ((userAgentHeader == null || userAgentHeader.trim().isEmpty())
-        && (headerUserAgent == null || headerUserAgent.trim().isEmpty())
-        && trackerConfiguration.getUserAgent() != null
+    if (trackerConfiguration.getUserAgent() != null
         && !trackerConfiguration.getUserAgent().isEmpty()) {
       builder.header("User-Agent", trackerConfiguration.getUserAgent());
     }