diff --git a/auto-pipeline-examples/src/test/java/com/foldright/examples/config/pipeline/ConfigSourceTest.kt b/auto-pipeline-examples/src/test/java/com/foldright/examples/config/pipeline/ConfigSourceTest.kt
index 0a0989e..4cb3d62 100644
--- a/auto-pipeline-examples/src/test/java/com/foldright/examples/config/pipeline/ConfigSourceTest.kt
+++ b/auto-pipeline-examples/src/test/java/com/foldright/examples/config/pipeline/ConfigSourceTest.kt
@@ -11,7 +11,7 @@ import io.kotest.matchers.shouldBe
 private const val NOT_EXISTED = "not_existed_key"
 
 class ConfigSourceTest : AnnotationSpec() {
-    lateinit var pipeline: ConfigSource
+    private lateinit var pipeline: ConfigSource
 
     @AfterEach
     fun afterEach() {
diff --git a/auto-pipeline-examples/src/test/java/com/foldright/examples/duplexing/pipeline/RPCTest.kt b/auto-pipeline-examples/src/test/java/com/foldright/examples/duplexing/pipeline/RPCTest.kt
index 724000a..a39d056 100644
--- a/auto-pipeline-examples/src/test/java/com/foldright/examples/duplexing/pipeline/RPCTest.kt
+++ b/auto-pipeline-examples/src/test/java/com/foldright/examples/duplexing/pipeline/RPCTest.kt
@@ -8,7 +8,7 @@ import io.kotest.core.spec.style.AnnotationSpec
 import io.kotest.matchers.shouldBe
 
 class RPCTest : AnnotationSpec() {
-    lateinit var pipeline: RPC
+    private lateinit var pipeline: RPC
 
 
     @Test
diff --git a/auto-pipeline-examples/src/test/java/com/foldright/examples/grpc/pipeline/ChannelTest.kt b/auto-pipeline-examples/src/test/java/com/foldright/examples/grpc/pipeline/ChannelTest.kt
index 51709c6..58ded2c 100644
--- a/auto-pipeline-examples/src/test/java/com/foldright/examples/grpc/pipeline/ChannelTest.kt
+++ b/auto-pipeline-examples/src/test/java/com/foldright/examples/grpc/pipeline/ChannelTest.kt
@@ -14,7 +14,7 @@ import io.kotest.matchers.types.shouldBeTypeOf
 
 class ChannelTest : AnnotationSpec() {
 
-    lateinit var pipeline: ChannelPipeline
+    private lateinit var pipeline: ChannelPipeline
 
     @Test
     fun testNoneHandler() {
diff --git a/auto-pipeline-examples/src/test/java/com/foldright/examples/lb/pipeline/LoadBalancerTest.kt b/auto-pipeline-examples/src/test/java/com/foldright/examples/lb/pipeline/LoadBalancerTest.kt
index ea0cd22..e6c66b3 100644
--- a/auto-pipeline-examples/src/test/java/com/foldright/examples/lb/pipeline/LoadBalancerTest.kt
+++ b/auto-pipeline-examples/src/test/java/com/foldright/examples/lb/pipeline/LoadBalancerTest.kt
@@ -15,7 +15,7 @@ class LoadBalancerTest : AnnotationSpec() {
         override fun available(): Boolean = available
     }
 
-    lateinit var pipeline: LoadBalancer
+    private lateinit var pipeline: LoadBalancer
 
     @Test
     fun testDefaultHandler() {