feat: add method to retrieve general instrumentation configuration by name

Author: zeitlinger

api/incubator/src/main/java/io/opentelemetry/api/incubator/config/ConfigProvider.java

@@ -42,10 +42,7 @@ public interface ConfigProvider {
    */
   default DeclarativeConfigProperties getJavaInstrumentationConfig(String name) {
     DeclarativeConfigProperties config = getInstrumentationConfig();
-    if (config == null) {
-      return empty();
-    }
-    return config.getStructured("java", empty()).getStructured(name, empty());
+    return config == null ? empty() : config.get("java").get(name);
   }
 
   /**
@@ -59,10 +56,7 @@ default DeclarativeConfigProperties getJavaInstrumentationConfig(String name) {
    */
   default DeclarativeConfigProperties getGeneralInstrumentationConfig(String name) {
     DeclarativeConfigProperties config = getInstrumentationConfig();
-    if (config == null) {
-      return empty();
-    }
-    return config.getStructured("general", empty()).getStructured(name, empty());
+    return config == null ? empty() : config.get("general").get(name);
   }
 
   /** Returns a no-op {@link ConfigProvider}. */

sdk-extensions/autoconfigure/src/testIncubating/java/io/opentelemetry/sdk/autoconfigure/DeclarativeConfigurationTest.java

@@ -5,7 +5,6 @@
 
 package io.opentelemetry.sdk.autoconfigure;
 
-import static io.opentelemetry.api.incubator.config.DeclarativeConfigProperties.empty;
 import static io.opentelemetry.sdk.testing.assertj.OpenTelemetryAssertions.assertThat;
 import static java.util.Collections.singletonMap;
 import static org.assertj.core.api.Assertions.assertThatCode;
@@ -239,7 +238,7 @@ void configFile_ConfigProvider() {
     assertThat(
             globalConfigProvider
                 .getGeneralInstrumentationConfig("http")
-                .getStructured("client", empty())
+                .get("client")
                 .getScalarList("request_captured_headers", String.class))
         .isEqualTo(Arrays.asList("Content-Type", "Accept"));
   }