fix(java-agent): resolve checkstyle violations in rollbar-java-agent

Author: buongarzoni

rollbar-java-agent/src/main/java/com/rollbar/agent/NetworkEventBridge.java

@@ -37,6 +37,11 @@ public static boolean markAsRecorded(Object key) {
     return RECORDED.add(key);
   }
 
+  /**
+   * Records a network telemetry event for the given key if not already recorded.
+   *
+   * <p>Uses the key as a deduplication token — subsequent calls with the same key are ignored.
+   */
   public static void recordNetworkEvent(Object key, String method, String url, String statusCode) {
     if (!markAsRecorded(key)) {
       return; // deduplicate re-entrant calls for the same connection
@@ -50,6 +55,11 @@ public static void recordNetworkEvent(Object key, String method, String url, Str
     );
   }
 
+  /**
+   * Records a manual error telemetry event with the given message.
+   *
+   * <p>Called when an HTTP request fails with an I/O exception rather than a status code.
+   */
   public static void recordError(String message) {
     AgentTelemetryStore.getInstance().recordManualEventFor(
         Level.CRITICAL,

rollbar-java-agent/src/main/java/com/rollbar/agent/RollbarAgent.java

@@ -5,11 +5,10 @@
 import com.rollbar.agent.instrumentation.HttpURLConnectionInstrumentation;
 import com.rollbar.agent.instrumentation.JavaHttpClientInstrumentation;
 import com.rollbar.notifier.telemetry.TelemetryEventTracker;
+import java.lang.instrument.Instrumentation;
 import net.bytebuddy.agent.builder.AgentBuilder;
 import net.bytebuddy.matcher.ElementMatchers;
 
-import java.lang.instrument.Instrumentation;
-
 /**
  * Java agent entry point. Attach with {@code -javaagent:/path/to/rollbar-java-agent.jar}.
  *

rollbar-java-agent/src/main/java/com/rollbar/agent/instrumentation/ApacheHttpClient4Instrumentation.java

@@ -4,18 +4,25 @@
 import com.rollbar.agent.UrlSanitizer;
 import com.rollbar.api.payload.data.Level;
 import com.rollbar.api.payload.data.Source;
+import java.lang.instrument.Instrumentation;
 import net.bytebuddy.agent.builder.AgentBuilder;
 import net.bytebuddy.asm.Advice;
 import net.bytebuddy.matcher.ElementMatchers;
 import org.apache.http.HttpResponse;
 import org.apache.http.client.methods.HttpUriRequest;
 
-import java.lang.instrument.Instrumentation;
-
+/**
+ * Installs ByteBuddy advice on Apache HttpClient 4.x to capture network errors.
+ */
 public final class ApacheHttpClient4Instrumentation {
 
   private ApacheHttpClient4Instrumentation() {}
 
+  /**
+   * Instruments Apache HttpClient 4.x if present on the classpath.
+   *
+   * <p>Does nothing if {@code org.apache.http.impl.client.CloseableHttpClient} is not available.
+   */
   public static void installIfAvailable(AgentBuilder builder, Instrumentation inst) {
     try {
       Class.forName("org.apache.http.impl.client.CloseableHttpClient");
@@ -41,6 +48,12 @@ public static void installIfAvailable(AgentBuilder builder, Instrumentation inst
    */
   public static class ExecuteAdvice {
 
+    /**
+     * Fires after {@code execute()} returns or throws, recording 4xx/5xx responses as telemetry.
+     *
+     * <p>Apache HC 4.x runs in the application classloader, so Rollbar classes are referenced
+     * directly without the TCCL reflection bridge needed for JDK instrumentation.
+     */
     @Advice.OnMethodExit(onThrowable = Throwable.class)
     public static void onExit(
         @Advice.Argument(0) HttpUriRequest request,
@@ -49,10 +62,12 @@ public static void onExit(
     ) {
       try {
         if (thrown != null) {
+          String message = thrown.getMessage() != null
+              ? thrown.getMessage() : thrown.getClass().getName();
           AgentTelemetryStore.getInstance().recordManualEventFor(
               Level.CRITICAL,
               Source.SERVER,
-              "Network error: " + (thrown.getMessage() != null ? thrown.getMessage() : thrown.getClass().getName())
+              "Network error: " + message
           );
           return;
         }

rollbar-java-agent/src/main/java/com/rollbar/agent/instrumentation/ApacheHttpClient5Instrumentation.java

@@ -4,18 +4,26 @@
 import com.rollbar.agent.UrlSanitizer;
 import com.rollbar.api.payload.data.Level;
 import com.rollbar.api.payload.data.Source;
+import java.lang.instrument.Instrumentation;
 import net.bytebuddy.agent.builder.AgentBuilder;
 import net.bytebuddy.asm.Advice;
 import net.bytebuddy.matcher.ElementMatchers;
 import org.apache.hc.core5.http.ClassicHttpRequest;
 import org.apache.hc.core5.http.ClassicHttpResponse;
 
-import java.lang.instrument.Instrumentation;
-
+/**
+ * Installs ByteBuddy advice on Apache HttpClient 5.x to capture network errors.
+ */
 public final class ApacheHttpClient5Instrumentation {
 
   private ApacheHttpClient5Instrumentation() {}
 
+  /**
+   * Instruments Apache HttpClient 5.x if present on the classpath.
+   *
+   * <p>Does nothing if {@code org.apache.hc.client5.http.impl.classic.CloseableHttpClient}
+   * is not available.
+   */
   public static void installIfAvailable(AgentBuilder builder, Instrumentation inst) {
     try {
       Class.forName("org.apache.hc.client5.http.impl.classic.CloseableHttpClient");
@@ -41,6 +49,12 @@ public static void installIfAvailable(AgentBuilder builder, Instrumentation inst
    */
   public static class ExecuteAdvice {
 
+    /**
+     * Fires after {@code execute()} returns or throws, recording 4xx/5xx responses as telemetry.
+     *
+     * <p>Apache HC 5.x runs in the application classloader, so Rollbar classes are referenced
+     * directly without the TCCL reflection bridge needed for JDK instrumentation.
+     */
     @Advice.OnMethodExit(onThrowable = Throwable.class)
     public static void onExit(
         @Advice.Argument(0) ClassicHttpRequest request,
@@ -49,10 +63,12 @@ public static void onExit(
     ) {
       try {
         if (thrown != null) {
+          String message = thrown.getMessage() != null
+              ? thrown.getMessage() : thrown.getClass().getName();
           AgentTelemetryStore.getInstance().recordManualEventFor(
               Level.CRITICAL,
               Source.SERVER,
-              "Network error: " + (thrown.getMessage() != null ? thrown.getMessage() : thrown.getClass().getName())
+              "Network error: " + message
           );
           return;
         }

rollbar-java-agent/src/main/java/com/rollbar/agent/instrumentation/HttpURLConnectionInstrumentation.java

@@ -1,15 +1,22 @@
 package com.rollbar.agent.instrumentation;
 
+import java.lang.instrument.Instrumentation;
 import net.bytebuddy.agent.builder.AgentBuilder;
 import net.bytebuddy.asm.Advice;
 import net.bytebuddy.matcher.ElementMatchers;
 
-import java.lang.instrument.Instrumentation;
-
+/**
+ * Installs ByteBuddy advice on {@code java.net.HttpURLConnection} to capture network errors.
+ */
 public final class HttpURLConnectionInstrumentation {
 
   private HttpURLConnectionInstrumentation() {}
 
+  /**
+   * Instruments {@code java.net.HttpURLConnection.getResponseCode()} to record 4xx/5xx responses.
+   *
+   * <p>Targets the declaring class directly to capture the method regardless of concrete subtype.
+   */
   public static void install(AgentBuilder builder, Instrumentation inst) {
     builder
         .type(ElementMatchers.named("java.net.HttpURLConnection"))
@@ -29,6 +36,12 @@ public static void install(AgentBuilder builder, Instrumentation inst) {
    */
   public static class GetResponseCodeAdvice {
 
+    /**
+     * Fires after {@code getResponseCode()} returns or throws, recording 4xx/5xx as telemetry.
+     *
+     * <p>Uses the connection instance as a deduplication key since {@code getResponseCode()} is
+     * called re-entrantly up to 3 times per request internally.
+     */
     @Advice.OnMethodExit(onThrowable = Throwable.class)
     public static void onExit(
         @Advice.This Object connection,
@@ -46,7 +59,8 @@ public static void onExit(
           Boolean recorded = (Boolean) bridge
               .getMethod("markAsRecorded", Object.class).invoke(null, thrown);
           if (recorded) {
-            String msg = thrown.getMessage() != null ? thrown.getMessage() : thrown.getClass().getName();
+            String msg = thrown.getMessage() != null
+                ? thrown.getMessage() : thrown.getClass().getName();
             bridge.getMethod("recordError", String.class).invoke(null, msg);
           }
           return;
@@ -55,8 +69,8 @@ public static void onExit(
         if (statusCode >= 400) {
           Object url = connection.getClass().getMethod("getURL").invoke(connection);
           String urlStr = url != null ? url.toString() : "";
-          String method = (String) connection.getClass().getMethod("getRequestMethod").invoke(connection);
-          // connection instance as dedup key — same object across all re-entrant getResponseCode() calls
+          String method = (String) connection.getClass()
+              .getMethod("getRequestMethod").invoke(connection);
           bridge.getMethod("recordNetworkEvent",
                   Object.class, String.class, String.class, String.class)
               .invoke(null, connection, method, urlStr, String.valueOf(statusCode));

rollbar-java-agent/src/main/java/com/rollbar/agent/instrumentation/JavaHttpClientInstrumentation.java

@@ -1,16 +1,23 @@
 package com.rollbar.agent.instrumentation;
 
+import java.lang.instrument.Instrumentation;
+import java.net.http.HttpClient;
 import net.bytebuddy.agent.builder.AgentBuilder;
 import net.bytebuddy.asm.Advice;
 import net.bytebuddy.matcher.ElementMatchers;
 
-import java.lang.instrument.Instrumentation;
-import java.net.http.HttpClient;
-
+/**
+ * Installs ByteBuddy advice on {@code java.net.http.HttpClient} subtypes to capture network errors.
+ */
 public final class JavaHttpClientInstrumentation {
 
   private JavaHttpClientInstrumentation() {}
 
+  /**
+   * Instruments {@code java.net.http.HttpClient} subtypes if available on the current JVM.
+   *
+   * <p>Does nothing if {@code java.net.http.HttpClient} is not present (i.e. below Java 11).
+   */
   public static void installIfAvailable(AgentBuilder builder, Instrumentation inst) {
     try {
       Class.forName("java.net.http.HttpClient");
@@ -37,6 +44,12 @@ public static void installIfAvailable(AgentBuilder builder, Instrumentation inst
    */
   public static class SendAdvice {
 
+    /**
+     * Fires after {@code send()} returns or throws, recording 4xx/5xx responses as telemetry.
+     *
+     * <p>Uses the response object as a deduplication key to avoid duplicate events when both
+     * {@code HttpClientFacade} and {@code HttpClientImpl} invoke this advice.
+     */
     @Advice.OnMethodExit(onThrowable = Throwable.class)
     public static void onExit(
         @Advice.Argument(0) Object request,
@@ -54,8 +67,9 @@ public static void onExit(
           Boolean recorded = (Boolean) bridge
               .getMethod("markAsRecorded", Object.class).invoke(null, thrown);
           if (recorded) {
-            String msg = thrown.getMessage() != null ? thrown.getMessage() : thrown.getClass().getName();
-            bridge.getMethod("recordError", String.class).invoke(null, msg);
+            String message = thrown.getMessage() != null
+                ? thrown.getMessage() : thrown.getClass().getName();
+            bridge.getMethod("recordError", String.class).invoke(null, message);
           }
           return;
         }