diff --git a/build.gradle b/build.gradle
index 02b76ba..6f3ca3d 100644
--- a/build.gradle
+++ b/build.gradle
@@ -82,7 +82,7 @@ tasks.withType(Javadoc) {
 patchPluginXml {
     // The performance of 2019.3 has been greatly improved.
     // change plugins without restarting the IDE in 2020.1.
-    // 2020.2 JCEF, 2022.3 JDK17, 2023.3 AI
+    // 2020.2 JCEF, 2022.2 JDK17 java2d perf improved, 2023.3 AI
     sinceBuild = '201.1'
     untilBuild = ''
     changeNotes = """
diff --git a/src/main/idea/io/github/linwancen/plugin/show/java/doc/AnnoDoc.java b/src/main/idea/io/github/linwancen/plugin/show/java/doc/AnnoDoc.java
index 50250e0..6f6a107 100644
--- a/src/main/idea/io/github/linwancen/plugin/show/java/doc/AnnoDoc.java
+++ b/src/main/idea/io/github/linwancen/plugin/show/java/doc/AnnoDoc.java
@@ -98,7 +98,7 @@ public class AnnoDoc {
     }
 
     @Nullable
-    private static String annoDocValue(PsiAnnotationMemberValue value) {
+    private static String annoDocValue(@Nullable PsiAnnotationMemberValue value) {
         if (value == null) {
             return null;
         }
diff --git a/src/main/java/io/github/linwancen/plugin/show/LineEnd.java b/src/main/java/io/github/linwancen/plugin/show/LineEnd.java
index 374906c..b8a91ca 100644
--- a/src/main/java/io/github/linwancen/plugin/show/LineEnd.java
+++ b/src/main/java/io/github/linwancen/plugin/show/LineEnd.java
@@ -91,7 +91,7 @@ public class LineEnd extends EditorLinePainter {
     }
 
     @NotNull
-    public static LineExtensionInfo lineExtText(@NotNull LineInfo info, String text) {
+    public static LineExtensionInfo lineExtText(@NotNull LineInfo info, @NotNull String text) {
         @NotNull TextAttributes textAttr = info.file.getFileType().equals(JsonFileType.INSTANCE)
                 || info.file.getFileType().equals(Json5FileType.INSTANCE)
                 ? info.appSettings.lineEndJsonTextAttr
diff --git a/src/main/java/io/github/linwancen/plugin/show/cache/LineEndCacheUtils.java b/src/main/java/io/github/linwancen/plugin/show/cache/LineEndCacheUtils.java
index d030160..10b45fe 100644
--- a/src/main/java/io/github/linwancen/plugin/show/cache/LineEndCacheUtils.java
+++ b/src/main/java/io/github/linwancen/plugin/show/cache/LineEndCacheUtils.java
@@ -65,7 +65,7 @@ public class LineEndCacheUtils {
 
     private static volatile boolean isRun = false;
 
-    private static void checkScheduleAndInit(Project project) {
+    private static void checkScheduleAndInit(@NotNull Project project) {
         if (!isRun) {
             if (DumbService.isDumb(project)) {
                 return;
@@ -119,7 +119,7 @@ public class LineEndCacheUtils {
                                 if (list != null) {
                                     list.add(lineExt);
                                 } else {
-                                    ArrayList<LineExtensionInfo> lineExtList = new ArrayList<>(1);
+                                    @NotNull ArrayList<LineExtensionInfo> lineExtList = new ArrayList<>(1);
                                     lineExtList.add(lineExt);
                                     lineCache.map.put(info.text, lineExtList);
                                 }
diff --git a/src/main/java/io/github/linwancen/plugin/show/cache/TreeCacheUtils.java b/src/main/java/io/github/linwancen/plugin/show/cache/TreeCacheUtils.java
index 7ccc5cf..4079cd1 100644
--- a/src/main/java/io/github/linwancen/plugin/show/cache/TreeCacheUtils.java
+++ b/src/main/java/io/github/linwancen/plugin/show/cache/TreeCacheUtils.java
@@ -40,7 +40,7 @@ public class TreeCacheUtils {
 
     private static volatile boolean isRun = false;
 
-    private static void checkScheduleAndInit(Project project) {
+    private static void checkScheduleAndInit(@NotNull Project project) {
         if (!isRun) {
             if (DumbService.isDumb(project)) {
                 return;
diff --git a/src/main/java/io/github/linwancen/plugin/show/settings/ProjectSettingsComponent.java b/src/main/java/io/github/linwancen/plugin/show/settings/ProjectSettingsComponent.java
index 76482c9..dc13de9 100644
--- a/src/main/java/io/github/linwancen/plugin/show/settings/ProjectSettingsComponent.java
+++ b/src/main/java/io/github/linwancen/plugin/show/settings/ProjectSettingsComponent.java
@@ -10,6 +10,7 @@ import javax.swing.*;
 
 public class ProjectSettingsComponent extends AbstractSettingsComponent {
 
+    @NotNull
     private final JBScrollPane myMainPanel;
     private final JBCheckBox globalFilterEffective = new JBCheckBox(ShowBundle.message("global.settings.effective"));
     private final JBCheckBox projectFilterEffective = new JBCheckBox(ShowBundle.message("project.settings.effective"));
@@ -25,11 +26,12 @@ public class ProjectSettingsComponent extends AbstractSettingsComponent {
                 .addComponent(commonPanel(), 1)
                 .addComponentFillVertically(new JPanel(), 0)
                 .getPanel();
-        JBScrollPane scrollPane = new JBScrollPane(panel);
+        @NotNull JBScrollPane scrollPane = new JBScrollPane(panel);
         scrollPane.setBorder(null);
         myMainPanel = scrollPane;
     }
 
+    @NotNull
     public JBScrollPane getPanel() {
         return myMainPanel;
     }