fix(p2p): address review findings for dependency and API compatibility

- Replace BasicThreadFactory.builder() with new BasicThreadFactory.Builder()
  to use commons-lang3 3.4-compatible API, preventing implicit global
  version upgrade from 3.4 to 3.18.0
- Remove unused grpc-core dependency (p2p protos define only messages,
  no gRPC services); retain grpc-netty as Netty transport provider
- Add p2p/.gitignore to exclude proto-generated code for all developers
- Update verification-metadata.xml for changed dependency tree

Author: Barbatos

gradle/verification-metadata.xml

@@ -372,6 +372,9 @@
          </artifact>
       </component>
       <component group="com.google.errorprone" name="error_prone_annotations" version="2.18.0">
+         <artifact name="error_prone_annotations-2.18.0.jar">
+            <sha256 value="9e6814cb71816988a4fd1b07a993a8f21bb7058d522c162b1de849e19bea54ae" origin="Generated by Gradle"/>
+         </artifact>
          <artifact name="error_prone_annotations-2.18.0.pom">
             <sha256 value="920135797dcca5917b5a5c017642a58d340a4cd1bcd12f56f892a5663bd7bddc" origin="Generated by Gradle"/>
          </artifact>

p2p/.gitignore

@@ -0,0 +1,2 @@
+# protobuf generated code (rebuilt by ./gradlew :p2p:generateProto)
+src/main/java/org/tron/p2p/protos/

p2p/build.gradle

@@ -13,7 +13,6 @@ checkstyleMain {
 }
 
 def protobufVersion = '3.25.8'
-def grpcVersion = '1.75.0'
 
 sourceSets {
     main {
@@ -30,8 +29,9 @@ dependencies {
     // protobuf & grpc (implementation scope: not leaked to consumers)
     implementation "com.google.protobuf:protobuf-java:${protobufVersion}"
     implementation "com.google.protobuf:protobuf-java-util:${protobufVersion}"
-    implementation "io.grpc:grpc-netty:${grpcVersion}"
-    implementation "io.grpc:grpc-core:${grpcVersion}"
+    // grpc-netty provides Netty transitively, which p2p uses for TCP/UDP transport.
+    // grpc itself is not used (p2p protos define only messages, no services).
+    implementation "io.grpc:grpc-netty:1.75.0"
 
     // p2p-specific dependencies
     implementation 'org.xerial.snappy:snappy-java:1.1.10.5'
@@ -58,10 +58,9 @@ dependencies {
         exclude group: 'xpp3', module: 'xpp3'
     }
 
-    // commons-lang3: libp2p uses BasicThreadFactory.builder() which requires 3.12+.
-    // Root build.gradle provides 3.4 globally but as 'implementation' (not on compile classpath).
-    // Declare 3.18.0 (matching original libp2p) to ensure API compatibility.
-    implementation 'org.apache.commons:commons-lang3:3.18.0'
+    // commons-lang3: root provides 3.4 as 'implementation' (not on compile classpath).
+    // Re-declare here so p2p can compile. Uses 3.4-compatible API (new Builder() not builder()).
+    implementation 'org.apache.commons:commons-lang3:3.4'
 
     // provided by root build.gradle for all subprojects:
     // slf4j-api, logback, bcprov-jdk18on, lombok, junit, mockito
@@ -72,22 +71,12 @@ protobuf {
     protoc {
         artifact = "com.google.protobuf:protoc:${protobufVersion}"
     }
-    plugins {
-        grpc {
-            artifact = "io.grpc:protoc-gen-grpc-java:${rootProject.archInfo.requires.ProtocGenVersion}"
-        }
-    }
     generateProtoTasks {
         all().each { task ->
             task.builtins {
                 java { outputSubDir = "java" }
             }
         }
-        all()*.plugins {
-            grpc {
-                outputSubDir = "java"
-            }
-        }
     }
 }
 

p2p/src/main/java/org/tron/p2p/connection/business/detect/NodeDetectService.java

@@ -37,7 +37,7 @@ public class NodeDetectService implements MessageProcess {
 
   private final ScheduledExecutorService executor =
       Executors.newSingleThreadScheduledExecutor(
-          BasicThreadFactory.builder().namingPattern("nodeDetectService").build());
+          new BasicThreadFactory.Builder().namingPattern("nodeDetectService").build());
 
   private final long NODE_DETECT_THRESHOLD = 5 * 60 * 1000;
 

p2p/src/main/java/org/tron/p2p/connection/business/keepalive/KeepAliveService.java

@@ -22,7 +22,7 @@ public class KeepAliveService implements MessageProcess {
 
   private final ScheduledExecutorService executor =
       Executors.newSingleThreadScheduledExecutor(
-          BasicThreadFactory.builder().namingPattern("keepAlive").build());
+          new BasicThreadFactory.Builder().namingPattern("keepAlive").build());
 
   public void init() {
     executor.scheduleWithFixedDelay(

p2p/src/main/java/org/tron/p2p/connection/business/pool/ConnPoolService.java

@@ -54,10 +54,10 @@ public class ConnPoolService extends P2pEventHandler {
   @Getter private final AtomicInteger connectingPeersCount = new AtomicInteger(0);
   private final ScheduledThreadPoolExecutor poolLoopExecutor =
       new ScheduledThreadPoolExecutor(
-          1, BasicThreadFactory.builder().namingPattern("connPool").build());
+          1, new BasicThreadFactory.Builder().namingPattern("connPool").build());
   private final ScheduledExecutorService disconnectExecutor =
       Executors.newSingleThreadScheduledExecutor(
-          BasicThreadFactory.builder().namingPattern("randomDisconnect").build());
+          new BasicThreadFactory.Builder().namingPattern("randomDisconnect").build());
 
   public P2pConfig p2pConfig = Parameter.p2pConfig;
   private PeerClient peerClient;

p2p/src/main/java/org/tron/p2p/connection/socket/PeerClient.java

@@ -24,7 +24,7 @@ public class PeerClient {
   public void init() {
     workerGroup =
         new NioEventLoopGroup(
-            0, BasicThreadFactory.builder().namingPattern("peerClient-%d").build());
+            0, new BasicThreadFactory.Builder().namingPattern("peerClient-%d").build());
   }
 
   public void close() {

p2p/src/main/java/org/tron/p2p/connection/socket/PeerServer.java

@@ -38,12 +38,13 @@ public void close() {
 
   public void start(int port) {
     EventLoopGroup bossGroup =
-        new NioEventLoopGroup(1, BasicThreadFactory.builder().namingPattern("peerBoss").build());
+        new NioEventLoopGroup(
+            1, new BasicThreadFactory.Builder().namingPattern("peerBoss").build());
     // if threads = 0, it is number of core * 2
     EventLoopGroup workerGroup =
         new NioEventLoopGroup(
             Parameter.TCP_NETTY_WORK_THREAD_NUM,
-            BasicThreadFactory.builder().namingPattern("peerWorker-%d").build());
+            new BasicThreadFactory.Builder().namingPattern("peerWorker-%d").build());
     P2pChannelInitializer p2pChannelInitializer = new P2pChannelInitializer("", false, true);
     try {
       ServerBootstrap b = new ServerBootstrap();

p2p/src/main/java/org/tron/p2p/discover/protocol/kad/DiscoverTask.java

@@ -16,7 +16,7 @@ public class DiscoverTask {
 
   private ScheduledExecutorService discoverer =
       Executors.newSingleThreadScheduledExecutor(
-          BasicThreadFactory.builder().namingPattern("discoverTask").build());
+          new BasicThreadFactory.Builder().namingPattern("discoverTask").build());
 
   private KadService kadService;
 

p2p/src/main/java/org/tron/p2p/discover/protocol/kad/KadService.java

@@ -56,7 +56,7 @@ public void init() {
     }
     this.pongTimer =
         Executors.newSingleThreadScheduledExecutor(
-            BasicThreadFactory.builder().namingPattern("pongTimer").build());
+            new BasicThreadFactory.Builder().namingPattern("pongTimer").build());
     this.homeNode =
         new Node(
             Parameter.p2pConfig.getNodeID(),