From 3c757f78297241abc9c9a4f98919048d1cf30b39 Mon Sep 17 00:00:00 2001
From: jiangyuanshu <317787106@qq.com>
Date: Tue, 21 Nov 2023 17:40:29 +0800
Subject: [PATCH] feat(net):fix bug of method toString in BlockCapsule

---
 .../org/tron/core/capsule/BlockCapsule.java    |  3 +--
 .../tron/core/capsule/BlockCapsuleTest.java    | 18 ++++++++++++++++++
 2 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/chainbase/src/main/java/org/tron/core/capsule/BlockCapsule.java b/chainbase/src/main/java/org/tron/core/capsule/BlockCapsule.java
index 8baafcb5dd5..01ff7fb5365 100755
--- a/chainbase/src/main/java/org/tron/core/capsule/BlockCapsule.java
+++ b/chainbase/src/main/java/org/tron/core/capsule/BlockCapsule.java
@@ -56,7 +56,6 @@ public class BlockCapsule implements ProtoCapsule<Block> {
 
   private Block block;
   private List<TransactionCapsule> transactions = new ArrayList<>();
-  private StringBuilder toStringBuff = new StringBuilder();
   private boolean isSwitch;
   @Getter
   @Setter
@@ -314,7 +313,7 @@ public boolean hasWitnessSignature() {
 
   @Override
   public String toString() {
-    toStringBuff.setLength(0);
+    StringBuilder toStringBuff = new StringBuilder();
 
     toStringBuff.append("BlockCapsule \n[ ");
     toStringBuff.append("hash=").append(getBlockId()).append("\n");
diff --git a/framework/src/test/java/org/tron/core/capsule/BlockCapsuleTest.java b/framework/src/test/java/org/tron/core/capsule/BlockCapsuleTest.java
index 0dd078dedb0..3c86d893895 100644
--- a/framework/src/test/java/org/tron/core/capsule/BlockCapsuleTest.java
+++ b/framework/src/test/java/org/tron/core/capsule/BlockCapsuleTest.java
@@ -2,7 +2,9 @@
 
 import com.google.protobuf.ByteString;
 import java.io.IOException;
+import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.List;
 import lombok.extern.slf4j.Slf4j;
 import org.junit.AfterClass;
 import org.junit.Assert;
@@ -146,4 +148,20 @@ public void testGetTimeStamp() {
     Assert.assertEquals(1234L, blockCapsule0.getTimeStamp());
   }
 
+  @Test
+  public void testConcurrentToString() throws InterruptedException {
+    List<Thread> threadList = new ArrayList<>();
+    int n = 10;
+    for (int i = 0; i < n; i++) {
+      threadList.add(new Thread(() -> blockCapsule0.toString()));
+    }
+    for (int i = 0; i < n; i++) {
+      threadList.get(i).start();
+    }
+    for (int i = 0; i < n; i++) {
+      threadList.get(i).join();
+    }
+    Assert.assertTrue(true);
+  }
+
 }