fix minor exceptions

src/main/java/io/zhile/research/intellij/ier/common/LicenseFileRecord.java

@@ -9,15 +9,16 @@ import java.util.Date;
 public class LicenseFileRecord implements EvalRecord {
     private final String type = "LICENSE";
     private final File file;
-    private final Date expireDate;
+
+    private String expireDate;
 
     public LicenseFileRecord(File file) {
         this.file = file;
 
         try (DataInputStream dis = new DataInputStream(new FileInputStream(file))) {
-            expireDate = new Date(~dis.readLong() + 2592000000L);
+            expireDate = DateTime.DF_DATETIME.format(new Date(~dis.readLong() + 2592000000L));
         } catch (Exception e) {
-            throw new RuntimeException(e);
+            expireDate = "ERROR";
         }
     }
 
@@ -34,6 +35,6 @@ public class LicenseFileRecord implements EvalRecord {
 
     @Override
     public String toString() {
-        return type + ": " + file.getName() + ", UNTIL: " + DateTime.DF_DATETIME.format(expireDate);
+        return type + ": " + file.getName() + ", UNTIL: " + expireDate;
     }
 }

src/main/java/io/zhile/research/intellij/ier/listener/AppActivationListener.java

@@ -15,14 +15,18 @@ import io.zhile.research.intellij.ier.helper.ResetTimeHelper;
 import org.jetbrains.annotations.NotNull;
 
 public class AppActivationListener implements ApplicationActivationListener, Disposable {
-    private static AppActivationListener instance = new AppActivationListener();
+    private static AppActivationListener instance;
     private static MessageBusConnection connection;
 
     protected AppActivationListener() {
 
     }
 
-    public static AppActivationListener getInstance() {
+    public synchronized static AppActivationListener getInstance() {
+        if (instance == null) {
+            instance = new AppActivationListener();
+        }
+
         return instance;
     }
 

src/main/java/io/zhile/research/intellij/ier/listener/AppEventListener.java

@@ -13,14 +13,18 @@ import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
 public class AppEventListener implements AppLifecycleListener, Disposable {
-    private static AppEventListener instance = new AppEventListener();
+    private static AppEventListener instance;
     private static MessageBusConnection connection;
 
     protected AppEventListener() {
 
     }
 
-    public static AppEventListener getInstance() {
+    public synchronized static AppEventListener getInstance() {
+        if (instance == null) {
+            instance = new AppEventListener();
+        }
+
         return instance;
     }
 

src/main/java/io/zhile/research/intellij/ier/listener/BrokenPluginsListener.java

@@ -9,14 +9,18 @@ import io.zhile.research.intellij.ier.helper.BrokenPlugins;
 import org.jetbrains.annotations.NotNull;
 
 public class BrokenPluginsListener implements ApplicationActivationListener, Disposable {
-    private static BrokenPluginsListener instance = new BrokenPluginsListener();
+    private static BrokenPluginsListener instance;
     private static MessageBusConnection connection;
 
     protected BrokenPluginsListener() {
 
     }
 
-    public static BrokenPluginsListener getInstance() {
+    public synchronized static BrokenPluginsListener getInstance() {
+        if (instance == null) {
+            instance = new BrokenPluginsListener();
+        }
+
         return instance;
     }
 

src/main/java/io/zhile/research/intellij/ier/listener/PluginListener.java

@@ -20,7 +20,7 @@ public class PluginListener implements DynamicPluginListener {
         }
 
         ActionManager.getInstance().getAction(Constants.RESET_ACTION_ID);
-        NotificationHelper.showInfo(null, "Plugin installed successfully! Now enjoy it~<br>For more information, visit <a href='https://zhile.io/2020/11/18/jetbrains-eval-reset.html'>here</a>.");
+        NotificationHelper.showInfo(null, "Plugin installed successfully! Now enjoy it~<br>For more information, visit <a href='https://zhile.io/2020/11/18/jetbrains-eval-reset-da33a93d.html'>here</a>.");
     }
 
     @Override

src/main/resources/META-INF/plugin.xml

@@ -7,7 +7,7 @@
     I can reset your IDE eval information.<br>
     <em>Click "Help" menu and select "Eval Reset"</em><br><br>
     <p>
-        <a href="https://zhile.io/2020/11/18/jetbrains-eval-reset.html" target="_blank">Need Help?</a>
+        <a href="https://zhile.io/2020/11/18/jetbrains-eval-reset-da33a93d.html" target="_blank">Need Help?</a>
     </p>
     ]]></description>