diff --git a/demo/java-demo/src/test/java/com/alibaba/testable/demo/DemoMockTest.java b/demo/java-demo/src/test/java/com/alibaba/testable/demo/DemoMockTest.java
index 7a1667b..c4e6b78 100644
--- a/demo/java-demo/src/test/java/com/alibaba/testable/demo/DemoMockTest.java
+++ b/demo/java-demo/src/test/java/com/alibaba/testable/demo/DemoMockTest.java
@@ -1,10 +1,10 @@
 package com.alibaba.testable.demo;
 
 import com.alibaba.testable.core.annotation.TestableMock;
+import com.alibaba.testable.core.tool.TestableConst;
 import com.alibaba.testable.demo.model.BlackBox;
 import org.junit.jupiter.api.Test;
 
-import java.io.IOException;
 import java.util.concurrent.Executors;
 
 import static com.alibaba.testable.core.matcher.InvokeVerifier.verify;
@@ -19,7 +19,7 @@ class DemoMockTest {
 
     private DemoMock demoMock = new DemoMock();
 
-    @TestableMock(targetMethod = CONSTRUCTOR)
+    @TestableMock(targetMethod = TestableConst.CONSTRUCTOR)
     private BlackBox createBlackBox(String text) {
         return new BlackBox("mock_" + text);
     }
diff --git a/demo/java-demo/src/test/java/com/alibaba/testable/demo/DemoTemplateTest.java b/demo/java-demo/src/test/java/com/alibaba/testable/demo/DemoTemplateTest.java
index 27bb2fd..e185efd 100644
--- a/demo/java-demo/src/test/java/com/alibaba/testable/demo/DemoTemplateTest.java
+++ b/demo/java-demo/src/test/java/com/alibaba/testable/demo/DemoTemplateTest.java
@@ -1,7 +1,7 @@
 package com.alibaba.testable.demo;
 
 import com.alibaba.testable.core.annotation.TestableMock;
-import com.alibaba.testable.core.tool.TestableTool;
+import com.alibaba.testable.core.tool.TestableConst;
 import org.junit.jupiter.api.Test;
 
 import java.util.*;
@@ -29,7 +29,7 @@ class DemoTemplateTest {
         return new HashMap<K, V>() {{ put(key, (V)(value.toString() + "_mock_map")); }};
     }
 
-    @TestableMock(targetMethod = TestableTool.CONSTRUCTOR)
+    @TestableMock(targetMethod = TestableConst.CONSTRUCTOR)
     private <T> HashSet<T> newHashSet() {
         HashSet<T> set = new HashSet<>();
         set.add((T)"insert_mock");
@@ -55,7 +55,7 @@ class DemoTemplateTest {
     //    return new HashMap<Object, Object>() {{ put(key, value.toString() + "_mock_map"); }};
     //}
     //
-    //@TestableMock(targetMethod = TestableTool.CONSTRUCTOR)
+    //@TestableMock(targetMethod = TestableConst.CONSTRUCTOR)
     //private HashSet newHashSet() {
     //    HashSet<Object> set = new HashSet<>();
     //    set.add("insert_mock");
diff --git a/demo/kotlin-demo/src/test/kotlin/com/alibaba/testable/demo/DemoMockTest.kt b/demo/kotlin-demo/src/test/kotlin/com/alibaba/testable/demo/DemoMockTest.kt
index 8b92f04..dd495fb 100644
--- a/demo/kotlin-demo/src/test/kotlin/com/alibaba/testable/demo/DemoMockTest.kt
+++ b/demo/kotlin-demo/src/test/kotlin/com/alibaba/testable/demo/DemoMockTest.kt
@@ -2,6 +2,7 @@ package com.alibaba.testable.demo
 
 import com.alibaba.testable.core.annotation.TestableMock
 import com.alibaba.testable.core.matcher.InvokeVerifier.verify
+import com.alibaba.testable.core.tool.TestableConst
 import com.alibaba.testable.core.tool.TestableTool.*
 import com.alibaba.testable.demo.model.BlackBox
 import com.alibaba.testable.demo.model.ColorBox
@@ -15,7 +16,7 @@ import java.util.concurrent.Executors
  */
 internal class DemoMockTest {
 
-    @TestableMock(targetMethod = CONSTRUCTOR)
+    @TestableMock(targetMethod = TestableConst.CONSTRUCTOR)
     private fun createBlackBox(text: String) = BlackBox("mock_$text")
 
     @TestableMock
diff --git a/demo/kotlin-demo/src/test/kotlin/com/alibaba/testable/demo/DemoTemplateTest.kt b/demo/kotlin-demo/src/test/kotlin/com/alibaba/testable/demo/DemoTemplateTest.kt
index 0f37974..26808fc 100644
--- a/demo/kotlin-demo/src/test/kotlin/com/alibaba/testable/demo/DemoTemplateTest.kt
+++ b/demo/kotlin-demo/src/test/kotlin/com/alibaba/testable/demo/DemoTemplateTest.kt
@@ -3,7 +3,7 @@ package com.alibaba.testable.demo
 import com.alibaba.testable.core.annotation.MockWith
 import com.alibaba.testable.core.annotation.TestableMock
 import com.alibaba.testable.core.model.MockDiagnose
-import com.alibaba.testable.core.tool.TestableTool
+import com.alibaba.testable.core.tool.TestableConst
 import org.junit.jupiter.api.Assertions
 import org.junit.jupiter.api.Test
 import java.util.*
@@ -27,7 +27,7 @@ internal class DemoTemplateTest {
         return mutableMapOf(key to (value.toString() + "_mock_map") as V)
     }
 
-    @TestableMock(targetMethod = TestableTool.CONSTRUCTOR)
+    @TestableMock(targetMethod = TestableConst.CONSTRUCTOR)
     private fun newHashSet(): HashSet<*> {
         val set = HashSet<Any>()
         set.add("insert_mock")
diff --git a/docs/zh-cn/doc/use-mock.md b/docs/zh-cn/doc/use-mock.md
index 2bbc564..26f8195 100644
--- a/docs/zh-cn/doc/use-mock.md
+++ b/docs/zh-cn/doc/use-mock.md
@@ -87,8 +87,8 @@ private BlackBox secretBox(BlackBox ignore) {
 ```java
 // 要覆写的构造函数签名为`BlackBox(String)`
 // 无需在Mock方法参数列表增加额外参数，由于使用了`targetMethod`参数，Mock方法的名称随意起
-// 此处的`CONSTRUCTOR`为`TestableTool`辅助类提供的常量，值为"<init>"
-@TestableMock(targetMethod = CONSTRUCTOR)
+// 此处的`TestableConst.CONSTRUCTOR`为`TestableMock`提供的辅助常量，值为"<init>"
+@TestableMock(targetMethod = TestableConst.CONSTRUCTOR)
 private BlackBox createBlackBox(String text) {
     return new BlackBox("mock_" + text);
 }
diff --git a/testable-agent/src/main/java/com/alibaba/testable/agent/constant/ConstPool.java b/testable-agent/src/main/java/com/alibaba/testable/agent/constant/ConstPool.java
index 150ee7c..8b0786a 100644
--- a/testable-agent/src/main/java/com/alibaba/testable/agent/constant/ConstPool.java
+++ b/testable-agent/src/main/java/com/alibaba/testable/agent/constant/ConstPool.java
@@ -8,7 +8,6 @@ public class ConstPool {
     public static final String DOT = ".";
     public static final String SLASH = "/";
 
-    public static final String CONSTRUCTOR = "<init>";
     public static final String TEST_POSTFIX = "Test";
     public static final String TESTABLE_INJECT_REF = "_testableInternalRef";
 
diff --git a/testable-agent/src/main/java/com/alibaba/testable/agent/handler/SourceClassHandler.java b/testable-agent/src/main/java/com/alibaba/testable/agent/handler/SourceClassHandler.java
index cd84836..d8a9656 100644
--- a/testable-agent/src/main/java/com/alibaba/testable/agent/handler/SourceClassHandler.java
+++ b/testable-agent/src/main/java/com/alibaba/testable/agent/handler/SourceClassHandler.java
@@ -4,6 +4,7 @@ import com.alibaba.testable.agent.constant.ConstPool;
 import com.alibaba.testable.agent.model.MethodInfo;
 import com.alibaba.testable.agent.util.BytecodeUtil;
 import com.alibaba.testable.agent.util.ClassUtil;
+import com.alibaba.testable.core.tool.TestableConst;
 import com.alibaba.testable.core.util.LogUtil;
 import org.objectweb.asm.Opcodes;
 import org.objectweb.asm.tree.*;
@@ -39,7 +40,7 @@ public class SourceClassHandler extends BaseClassHandler {
         Set<MethodInfo> memberInjectMethods = new HashSet<MethodInfo>();
         Set<MethodInfo> newOperatorInjectMethods = new HashSet<MethodInfo>();
         for (MethodInfo mi : injectMethods) {
-            if (mi.getName().equals(ConstPool.CONSTRUCTOR)) {
+            if (mi.getName().equals(TestableConst.CONSTRUCTOR)) {
                 newOperatorInjectMethods.add(mi);
             } else {
                 memberInjectMethods.add(mi);
@@ -68,7 +69,7 @@ public class SourceClassHandler extends BaseClassHandler {
                             node.owner, node.getOpcode(), rangeStart, i);
                         i = rangeStart;
                     }
-                } else if (ConstPool.CONSTRUCTOR.equals(node.name)) {
+                } else if (TestableConst.CONSTRUCTOR.equals(node.name)) {
                     // it's a new operation
                     String newOperatorInjectMethodName = getNewOperatorInjectMethodName(newOperatorInjectMethods, node);
                     if (newOperatorInjectMethodName != null) {
@@ -126,7 +127,7 @@ public class SourceClassHandler extends BaseClassHandler {
                 case Opcodes.INVOKEVIRTUAL:
                 case Opcodes.INVOKEINTERFACE:
                     stackLevel += stackEffectOfInvocation(instructions[i]) + 1;
-                    if (((MethodInsnNode)instructions[i]).name.equals(ConstPool.CONSTRUCTOR)) {
+                    if (((MethodInsnNode)instructions[i]).name.equals(TestableConst.CONSTRUCTOR)) {
                         // constructor must be INVOKESPECIAL and implicitly pop 1 more stack
                         stackLevel++;
                     }
diff --git a/testable-agent/src/main/java/com/alibaba/testable/agent/handler/TestClassHandler.java b/testable-agent/src/main/java/com/alibaba/testable/agent/handler/TestClassHandler.java
index 4c8f21d..ebcffe0 100644
--- a/testable-agent/src/main/java/com/alibaba/testable/agent/handler/TestClassHandler.java
+++ b/testable-agent/src/main/java/com/alibaba/testable/agent/handler/TestClassHandler.java
@@ -4,6 +4,7 @@ import com.alibaba.testable.agent.constant.ConstPool;
 import com.alibaba.testable.agent.tool.ImmutablePair;
 import com.alibaba.testable.agent.util.AnnotationUtil;
 import com.alibaba.testable.agent.util.ClassUtil;
+import com.alibaba.testable.core.tool.TestableConst;
 import org.objectweb.asm.tree.*;
 
 import java.util.ArrayList;
@@ -133,7 +134,7 @@ public class TestClassHandler extends BaseClassHandler {
         for (AnnotationNode an : mn.visibleAnnotations) {
             String method = AnnotationUtil.getAnnotationParameter
                 (an, ConstPool.FIELD_TARGET_METHOD, null, String.class);
-            if (ConstPool.CONSTRUCTOR.equals(method)) {
+            if (TestableConst.CONSTRUCTOR.equals(method)) {
                 return true;
             }
         }
diff --git a/testable-agent/src/main/java/com/alibaba/testable/agent/transformer/TestableClassTransformer.java b/testable-agent/src/main/java/com/alibaba/testable/agent/transformer/TestableClassTransformer.java
index 7a7eb1e..dfab51d 100644
--- a/testable-agent/src/main/java/com/alibaba/testable/agent/transformer/TestableClassTransformer.java
+++ b/testable-agent/src/main/java/com/alibaba/testable/agent/transformer/TestableClassTransformer.java
@@ -9,6 +9,7 @@ import com.alibaba.testable.agent.model.MethodInfo;
 import com.alibaba.testable.agent.tool.ComparableWeakRef;
 import com.alibaba.testable.agent.util.AnnotationUtil;
 import com.alibaba.testable.agent.util.ClassUtil;
+import com.alibaba.testable.core.tool.TestableConst;
 import com.alibaba.testable.core.util.LogUtil;
 import com.alibaba.testable.core.model.MockDiagnose;
 import org.objectweb.asm.ClassReader;
@@ -98,7 +99,7 @@ public class TestableClassTransformer implements ClassFileTransformer {
                 String targetClass = ClassUtil.toSlashSeparateFullClassName(methodDescPair.left);
                 String targetMethod = AnnotationUtil.getAnnotationParameter(
                     an, ConstPool.FIELD_TARGET_METHOD, mn.name, String.class);
-                if (targetMethod.equals(ConstPool.CONSTRUCTOR)) {
+                if (targetMethod.equals(TestableConst.CONSTRUCTOR)) {
                     String sourceClassName = ClassUtil.getSourceClassName(cn.name);
                     methodInfos.add(new MethodInfo(sourceClassName, targetMethod, mn.name, mn.desc));
                 } else {
diff --git a/testable-core/src/main/java/com/alibaba/testable/core/tool/TestableConst.java b/testable-core/src/main/java/com/alibaba/testable/core/tool/TestableConst.java
new file mode 100644
index 0000000..567d713
--- /dev/null
+++ b/testable-core/src/main/java/com/alibaba/testable/core/tool/TestableConst.java
@@ -0,0 +1,13 @@
+package com.alibaba.testable.core.tool;
+
+/**
+ * @author flin
+ */
+public class TestableConst {
+
+    /**
+     * Name of the constructor method
+     */
+    public static final String CONSTRUCTOR = "<init>";
+
+}
diff --git a/testable-core/src/main/java/com/alibaba/testable/core/tool/TestableTool.java b/testable-core/src/main/java/com/alibaba/testable/core/tool/TestableTool.java
index 47c5d38..126bae6 100644
--- a/testable-core/src/main/java/com/alibaba/testable/core/tool/TestableTool.java
+++ b/testable-core/src/main/java/com/alibaba/testable/core/tool/TestableTool.java
@@ -5,11 +5,6 @@ package com.alibaba.testable.core.tool;
  */
 public class TestableTool {
 
-    /**
-     * Name of the constructor method
-     */
-    public static final String CONSTRUCTOR = "<init>";
-
     /**
      * Name of current test case method
      */