Fix more Java warnings (#4376)

Author: trask

agent/agent-tooling/src/main/java/com/microsoft/applicationinsights/agent/internal/configuration/ConfigurationBuilder.java

@@ -104,7 +104,7 @@ public class ConfigurationBuilder {
   private static final String APPLICATIONINSIGHTS_PREVIEW_PROFILER_ENABLEDIAGNOSTICS =
       "APPLICATIONINSIGHTS_PREVIEW_PROFILER_ENABLEDIAGNOSTICS";
 
-  @Deprecated
+  // this env var is deprecated but supported for backwards compatibility
   private static final String APPLICATIONINSIGHTS_PREVIEW_METRIC_INTERVAL_SECONDS =
       "APPLICATIONINSIGHTS_PREVIEW_METRIC_INTERVAL_SECONDS";
 
@@ -141,6 +141,7 @@ public static Configuration create(
     return config;
   }
 
+  @SuppressWarnings("deprecation") // log usages of deprecated configuration options
   private static void logConfigurationWarnings(Configuration config) {
     if (config.instrumentation.micrometer.reportingIntervalSeconds != 60) {
       configurationLogger.warn(
@@ -354,6 +355,7 @@ private static void supportTelemetryProcessorsOldSemConv(Configuration config) {
     }
   }
 
+  @SuppressWarnings("deprecation") // support deprecated semconv for backwards compatibility
   private static String mapAttributeKey(String oldAttributeKey) {
     String result = null;
     // Common attributes across HTTP client and server spans
@@ -479,6 +481,7 @@ private static boolean isOpenJ9Jvm() {
     return jvmName != null && jvmName.contains("OpenJ9");
   }
 
+  @SuppressWarnings("deprecation") // support deprecated configuration for backwards compatibility
   private static void overlayAadEnvVars(
       Configuration config, Function<String, String> envVarsFunction) {
     String aadAuthString = getEnvVar(APPLICATIONINSIGHTS_AUTHENTICATION_STRING, envVarsFunction);

agent/agent-tooling/src/main/java/com/microsoft/applicationinsights/agent/internal/httpclient/LazyHttpClient.java

@@ -150,6 +150,7 @@ public Mono<HttpResponse> send(HttpRequest request, Context context) {
     return getDelegate().send(request, context);
   }
 
+  @SuppressWarnings("deprecation") // support deprecated configuration for backwards compatibility
   private static HttpPipelinePolicy getAuthenticationPolicy(
       Configuration.AadAuthentication configuration, String aadAudienceWithScope) {
     switch (configuration.type) {
@@ -174,6 +175,7 @@ private static HttpPipelinePolicy getAuthenticationPolicyWithUami(
         managedIdentityCredential.build(), aadAudienceWithScope);
   }
 
+  @Deprecated
   private static HttpPipelinePolicy getAuthenticationPolicyWithClientSecret(
       Configuration.AadAuthentication configuration, String aadAudienceWithScope) {
     ClientSecretCredentialBuilder credential =

agent/agent-tooling/src/main/java/com/microsoft/applicationinsights/agent/internal/init/AiContextCustomizer.java

@@ -34,6 +34,7 @@ public AiContextCustomizer(
   }
 
   @Override
+  @SuppressWarnings("deprecation") // support deprecated semconv for backwards compatibility
   public Context onStart(Context context, R request, Attributes startAttributes) {
 
     // TODO (trask) ideally would also check parentSpanContext !isValid || isRemote

agent/agent-tooling/src/main/java/com/microsoft/applicationinsights/agent/internal/profiler/service/ServiceProfilerClient.java

@@ -4,6 +4,7 @@
 package com.microsoft.applicationinsights.agent.internal.profiler.service;
 
 import com.azure.core.exception.HttpResponseException;
+import com.azure.core.http.HttpHeaderName;
 import com.azure.core.http.HttpMethod;
 import com.azure.core.http.HttpPipeline;
 import com.azure.core.http.HttpRequest;
@@ -69,7 +70,7 @@ private static BlobAccessPass getUploadAccess(HttpResponse response) {
       if (response.getStatusCode() >= 300) {
         throw new HttpResponseException(response);
       }
-      String location = response.getHeaderValue("Location");
+      String location = response.getHeaderValue(HttpHeaderName.LOCATION);
       if (location == null || location.isEmpty()) {
         throw new AssertionError("response did not have a location");
       }
@@ -86,7 +87,7 @@ public Mono<HttpResponse> executePostWithRedirect(URL requestUrl) {
 
     HttpRequest request = new HttpRequest(HttpMethod.POST, requestUrl);
     if (userAgent != null) {
-      request.setHeader("User-Agent", userAgent);
+      request.setHeader(HttpHeaderName.USER_AGENT, userAgent);
     }
     return httpPipeline.send(request);
   }

agent/agent-tooling/src/main/java/com/microsoft/applicationinsights/agent/internal/sampling/SamplingOverrides.java

@@ -122,6 +122,7 @@ private StrictMatcher(String key, String value) {
     }
 
     @Override
+    @SuppressWarnings("deprecation") // support deprecated semconv for backwards compatibility
     public boolean test(
         Attributes attributes, LazyHttpUrl lazyHttpUrl, LazyHttpTarget lazyHttpTarget) {
       String val = MatcherGroup.getValueIncludingThreadName(attributes, key);
@@ -213,6 +214,7 @@ private KeyOnlyMatcher(String key) {
     }
 
     @Override
+    @SuppressWarnings("deprecation") // support deprecated semconv for backwards compatibility
     public boolean test(
         Attributes attributes,
         @Nullable LazyHttpUrl lazyHttpUrl,
@@ -247,6 +249,7 @@ private String get() {
     }
   }
 
+  @SuppressWarnings("deprecation") // support deprecated semconv for backwards compatibility
   private static boolean getHttpUrlKeyOldOrStableSemconv(AttributeKey<String> key) {
     String keyString = key.getKey();
     return keyString.equals(HttpIncubatingAttributes.HTTP_URL.getKey())