From dd997c267a0cdd8b9ee2a4b9613e0ef06b23c062 Mon Sep 17 00:00:00 2001
From: hengyunabc <hengyunabc@gmail.com>
Date: Thu, 7 Jan 2021 22:46:36 +0800
Subject: [PATCH] retransform command print transformCount. #1651

---
 .../core/command/klass100/RetransformCommand.java    | 12 ++++++++----
 .../arthas/core/command/view/RetransformView.java    |  6 +++---
 site/src/site/sphinx/en/retransform.md               |  5 +++--
 site/src/site/sphinx/retransform.md                  |  6 ++++--
 4 files changed, 18 insertions(+), 11 deletions(-)

diff --git a/core/src/main/java/com/taobao/arthas/core/command/klass100/RetransformCommand.java b/core/src/main/java/com/taobao/arthas/core/command/klass100/RetransformCommand.java
index e2756ea04..fc4272587 100644
--- a/core/src/main/java/com/taobao/arthas/core/command/klass100/RetransformCommand.java
+++ b/core/src/main/java/com/taobao/arthas/core/command/klass100/RetransformCommand.java
@@ -280,8 +280,6 @@ public class RetransformCommand extends AnnotatedCommand {
                 classList.add(clazz);
                 retransformModel.addRetransformClass(clazz.getName());
 
-                addRetransformEntry(retransformEntry);
-
                 logger.info("Try retransform class name: {}, ClassLoader: {}", clazz.getName(), clazz.getClassLoader());
             }
         }
@@ -291,6 +289,7 @@ public class RetransformCommand extends AnnotatedCommand {
                 process.end(-1, "These classes are not found in the JVM and may not be loaded: " + bytesMap.keySet());
                 return;
             }
+            addRetransformEntry(retransformEntryList);
 
             inst.retransformClasses(classList.toArray(new Class[0]));
 
@@ -352,6 +351,10 @@ public class RetransformCommand extends AnnotatedCommand {
             this.classLoaderClass = classLoaderClass;
         }
 
+        public void incTransformCount() {
+            transformCount++;
+        }
+
         public int getId() {
             return id;
         }
@@ -401,10 +404,10 @@ public class RetransformCommand extends AnnotatedCommand {
         }
     }
 
-    public static synchronized void addRetransformEntry(RetransformEntry retransformEntry) {
+    public static synchronized void addRetransformEntry(List<RetransformEntry> retransformEntryList) {
         List<RetransformEntry> tmp = new ArrayList<RetransformEntry>();
         tmp.addAll(retransformEntries);
-        tmp.add(retransformEntry);
+        tmp.addAll(retransformEntryList);
         Collections.sort(tmp, new Comparator<RetransformEntry>() {
             @Override
             public int compare(RetransformEntry entry1, RetransformEntry entry2) {
@@ -468,6 +471,7 @@ public class RetransformCommand extends AnnotatedCommand {
                 if (updateFlag) {
                     logger.info("RetransformCommand match class: {}, id: {}, classLoaderClass: {}, hashCode: {}",
                             className, id, retransformEntry.getClassLoaderClass(), retransformEntry.getHashCode());
+                    retransformEntry.incTransformCount();
                     return retransformEntry.getBytes();
                 }
 
diff --git a/core/src/main/java/com/taobao/arthas/core/command/view/RetransformView.java b/core/src/main/java/com/taobao/arthas/core/command/view/RetransformView.java
index 9da84a8e0..5f64f1679 100644
--- a/core/src/main/java/com/taobao/arthas/core/command/view/RetransformView.java
+++ b/core/src/main/java/com/taobao/arthas/core/command/view/RetransformView.java
@@ -35,12 +35,12 @@ public class RetransformView extends ResultView<RetransformModel> {
         // retransform -l
         if (result.getRetransformEntries() != null) {
             // header
-            TableElement table = new TableElement(1, 1, 1, 1).rightCellPadding(1);
-            table.add(new RowElement().style(Decoration.bold.bold()).add("Id", "ClassName", "LoaderHash",
+            TableElement table = new TableElement(1, 1, 1, 1, 1).rightCellPadding(1);
+            table.add(new RowElement().style(Decoration.bold.bold()).add("Id", "ClassName", "TransformCount", "LoaderHash",
                     "LoaderClassName"));
 
             for (RetransformEntry entry : result.getRetransformEntries()) {
-                table.row("" + entry.getId(), "" + entry.getClassName(), "" + entry.getHashCode(),
+                table.row("" + entry.getId(), "" + entry.getClassName(), "" + entry.getTransformCount(), "" + entry.getHashCode(),
                         "" + entry.getClassLoaderClass());
             }
 
diff --git a/site/src/site/sphinx/en/retransform.md b/site/src/site/sphinx/en/retransform.md
index 80b289ac7..89ccf73d9 100644
--- a/site/src/site/sphinx/en/retransform.md
+++ b/site/src/site/sphinx/en/retransform.md
@@ -33,10 +33,11 @@ Load the specified .class file, then parse out the class name, and then retransf
 
 ```bash
 $ retransform -l
-Id ClassName LoaderHash LoaderClassName
-1 demo.MathGame null null
+Id              ClassName       TransformCount  LoaderHash      LoaderClassName
+1               demo.MathGame   1               null            null
 ```
 
+* TransformCount counts the times of attempts to return the .class file corresponding to the entry in the ClassFileTransformer#transform method, but it does not mean that the transform must be successful.
 ### Delete the specified retransform entry
 
 Need to specify id:
diff --git a/site/src/site/sphinx/retransform.md b/site/src/site/sphinx/retransform.md
index 6bc3d8b58..4964d29f5 100644
--- a/site/src/site/sphinx/retransform.md
+++ b/site/src/site/sphinx/retransform.md
@@ -34,10 +34,12 @@ demo.MathGame
 
 ```bash
 $ retransform -l
-Id                  ClassName           LoaderHash          LoaderClassName
-1                   demo.MathGame       null                null
+Id              ClassName       TransformCount  LoaderHash      LoaderClassName
+1               demo.MathGame   1               null            null
 ```
 
+* TransformCount 统计在 ClassFileTransformer#transform 函数里尝试返回 entry对应的 .class文件的次数，但并不表明transform一定成功。
+
 ### 删除指定 retransform entry
 
 需要指定 id：