azure-core: use classloader that loaded providers class to load individual provider classes (Azure#20760)

* azure-core: use classloader that loaded providers class to load individual provider classes

* fix HttpClientProviders: use HttpClientProviders classloader instead of HttpClientProvider

Co-authored-by: Srikanta <51379715+srnagar@users.noreply.github.com>

Co-authored-by: Srikanta <51379715+srnagar@users.noreply.github.com>

Author: ueisele

sdk/core/azure-core/src/main/java/com/azure/core/http/policy/HttpPolicyProviders.java

@@ -17,8 +17,15 @@ public final class HttpPolicyProviders {
     private static final List<AfterRetryPolicyProvider> AFTER_PROVIDER = new ArrayList<>();
 
     static {
-        ServiceLoader.load(BeforeRetryPolicyProvider.class).forEach(BEFORE_PROVIDER::add);
-        ServiceLoader.load(AfterRetryPolicyProvider.class).forEach(AFTER_PROVIDER::add);
+        // Use as classloader to load provider-configuration files and provider classes the classloader
+        // that loaded this class. In most cases this will be the System classloader.
+        // But this choice here provides additional flexibility in managed environments that control
+        // classloading differently (OSGi, Spring and others) and don't/ depend on the
+        // System classloader to load BeforeRetryPolicyProvider and AfterRetryPolicyProvider classes.
+        ServiceLoader.load(BeforeRetryPolicyProvider.class, HttpPolicyProviders.class.getClassLoader())
+            .forEach(BEFORE_PROVIDER::add);
+        ServiceLoader.load(AfterRetryPolicyProvider.class, HttpPolicyProviders.class.getClassLoader())
+            .forEach(AFTER_PROVIDER::add);
     }
 
     private HttpPolicyProviders() {

sdk/core/azure-core/src/main/java/com/azure/core/implementation/http/HttpClientProviders.java

@@ -23,7 +23,14 @@ public final class HttpClientProviders {
     private static HttpClientProvider defaultProvider;
 
     static {
-        ServiceLoader<HttpClientProvider> serviceLoader = ServiceLoader.load(HttpClientProvider.class);
+        // Use as classloader to load provider-configuration files and provider classes the classloader
+        // that loaded this class. In most cases this will be the System classloader.
+        // But this choice here provides additional flexibility in managed environments that control
+        // classloading differently (OSGi, Spring and others) and don't/ depend on the
+        // System classloader to load HttpClientProvider classes.
+        ServiceLoader<HttpClientProvider> serviceLoader = ServiceLoader.load(
+            HttpClientProvider.class,
+            HttpClientProviders.class.getClassLoader());
         // Use the first provider found in the service loader iterator.
         Iterator<HttpClientProvider> it = serviceLoader.iterator();
         if (it.hasNext()) {

sdk/core/azure-core/src/main/java/com/azure/core/util/serializer/JsonSerializerProviders.java

@@ -65,7 +65,14 @@ private static synchronized void loadDefaultSerializer() {
         }
 
         attemptedLoad = true;
-        Iterator<JsonSerializerProvider> iterator = ServiceLoader.load(JsonSerializerProvider.class).iterator();
+        // Use as classloader to load provider-configuration files and provider classes the classloader
+        // that loaded this class. In most cases this will be the System classloader.
+        // But this choice here provides additional flexibility in managed environments that control
+        // classloading differently (OSGi, Spring and others) and don't/ depend on the
+        // System classloader to load JsonSerializerProviders classes.
+        Iterator<JsonSerializerProvider> iterator =
+            ServiceLoader.load(JsonSerializerProvider.class, JsonSerializerProviders.class.getClassLoader())
+                .iterator();
         if (iterator.hasNext()) {
             jsonSerializerProvider = iterator.next();
         }

sdk/core/azure-core/src/main/java/com/azure/core/util/serializer/MemberNameConverterProviders.java

@@ -38,8 +38,14 @@ private static synchronized void loadFromClasspath() {
         }
 
         attemptedLoad = true;
+        // Use as classloader to load provider-configuration files and provider classes the classloader
+        // that loaded this class. In most cases this will be the System classloader.
+        // But this choice here provides additional flexibility in managed environments that control
+        // classloading differently (OSGi, Spring and others) and don't/ depend on the
+        // System classloader to load MemberNameConverterProviders classes.
         Iterator<MemberNameConverterProvider> iterator =
-            ServiceLoader.load(MemberNameConverterProvider.class).iterator();
+            ServiceLoader.load(MemberNameConverterProvider.class, MemberNameConverterProviders.class.getClassLoader())
+                .iterator();
         if (iterator.hasNext()) {
             defaultProvider = iterator.next();
         } else {

sdk/core/azure-core/src/main/java/com/azure/core/util/tracing/TracerProxy.java

@@ -18,7 +18,12 @@ public final class TracerProxy {
     private static Tracer tracer;
 
     static {
-        ServiceLoader<Tracer> serviceLoader = ServiceLoader.load(Tracer.class);
+        // Use as classloader to load provider-configuration files and provider classes the classloader
+        // that loaded this class. In most cases this will be the System classloader.
+        // But this choice here provides additional flexibility in managed environments that control
+        // classloading differently (OSGi, Spring and others) and don't/ depend on the
+        // System classloader to load Tracer classes.
+        ServiceLoader<Tracer> serviceLoader = ServiceLoader.load(Tracer.class, TracerProxy.class.getClassLoader());
         Iterator<?> iterator = serviceLoader.iterator();
         if (iterator.hasNext()) {
             tracer = serviceLoader.iterator().next();