refactor(http): replace reflection with @VisibleForTesting accessor and fix comment attribution

Add getMaxRequestSize()/setMaxRequestSize() to HttpService so tests
use compile-safe accessors instead of Field.setAccessible(true).
Correct comments attributing exception swallowing to RateLimiterServlet
when it is actually jsonrpc4j that silently absorbs the BadMessageException.

Author: bladehan1

framework/src/main/java/org/tron/common/application/HttpService.java

@@ -15,6 +15,7 @@
 
 package org.tron.common.application;
 
+import com.google.common.annotations.VisibleForTesting;
 import java.util.concurrent.CompletableFuture;
 import lombok.extern.slf4j.Slf4j;
 import org.eclipse.jetty.server.ConnectionLimit;
@@ -32,6 +33,16 @@ public abstract class HttpService extends AbstractService {
 
   protected long maxRequestSize = 4 * 1024 * 1024; // 4MB
 
+  @VisibleForTesting
+  public long getMaxRequestSize() {
+    return this.maxRequestSize;
+  }
+
+  @VisibleForTesting
+  public void setMaxRequestSize(long maxRequestSize) {
+    this.maxRequestSize = maxRequestSize;
+  }
+
   @Override
   public void innerStart() throws Exception {
     if (this.apiServer != null) {

framework/src/test/java/org/tron/core/jsonrpc/JsonrpcServiceTest.java

@@ -9,7 +9,7 @@
 import com.google.protobuf.ByteString;
 import io.prometheus.client.CollectorRegistry;
 import java.io.ByteArrayInputStream;
-import java.lang.reflect.Field;
+
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
@@ -1109,16 +1109,14 @@ public void testWeb3ClientVersion() {
    *
    * Covers: normal request no regression, Content-Length oversized 413,
    * and chunked oversized handled gracefully (body truncated, 200 + empty body
-   * because RateLimiterServlet absorbs the BadMessageException).
+   * because jsonrpc4j absorbs the BadMessageException).
    */
   @Test
   public void testJsonRpcSizeLimitIntegration() {
     long testLimit = 1024;
     try {
-      Field field = HttpService.class.getDeclaredField("maxRequestSize");
-      field.setAccessible(true);
-      long originalLimit = field.getLong(fullNodeJsonRpcHttpService);
-      field.setLong(fullNodeJsonRpcHttpService, testLimit);
+      long originalLimit = fullNodeJsonRpcHttpService.getMaxRequestSize();
+      fullNodeJsonRpcHttpService.setMaxRequestSize(testLimit);
 
       fullNodeJsonRpcHttpService.start();
       String url = "http://127.0.0.1:"
@@ -1151,7 +1149,7 @@ public void testJsonRpcSizeLimitIntegration() {
         resp.close();
 
         // Chunked oversized → BadMessageException thrown during body read,
-        // absorbed by RateLimiterServlet catch(Exception) → 200 with empty body.
+        // absorbed by jsonrpc4j catch(Exception) → 200 with empty body.
         // Body read IS truncated at the limit — OOM protection effective.
         byte[] chunkedData = new String(new char[(int) testLimit * 2])
             .replace('\0', 'x').getBytes("UTF-8");
@@ -1162,10 +1160,10 @@ public void testJsonRpcSizeLimitIntegration() {
         Assert.assertEquals(200, resp.getStatusLine().getStatusCode());
         body = EntityUtils.toString(resp.getEntity());
         Assert.assertTrue("Chunked oversized should return empty body"
-            + " (RateLimiterServlet absorbs BadMessageException)", body.isEmpty());
+            + " (jsonrpc4j absorbs BadMessageException)", body.isEmpty());
         resp.close();
       } finally {
-        field.setLong(fullNodeJsonRpcHttpService, originalLimit);
+        fullNodeJsonRpcHttpService.setMaxRequestSize(originalLimit);
       }
     } catch (Exception e) {
       Assert.fail(e.getMessage());