diff --git a/src/main/kotlin/com/waicool20/kaga/util/LockPreventer.kt b/src/main/kotlin/com/waicool20/kaga/util/LockPreventer.kt
index 3e19d45..818c30a 100644
--- a/src/main/kotlin/com/waicool20/kaga/util/LockPreventer.kt
+++ b/src/main/kotlin/com/waicool20/kaga/util/LockPreventer.kt
@@ -23,22 +23,19 @@ package com.waicool20.kaga.util
 import java.awt.Robot
 import java.awt.event.KeyEvent
 import java.util.*
+import kotlin.concurrent.timerTask
 
 class LockPreventer {
-    private var timer: Timer? = null
-    private val robot = Robot()
-    private val timerTask = object : TimerTask() {
-        override fun run() {
+    private val timer by lazy { Timer() }
+    private val robot by lazy { Robot() }
+    private val task by lazy {
+        timerTask {
             robot.keyPress(KeyEvent.VK_SHIFT)
             Thread.sleep(10)
             robot.keyRelease(KeyEvent.VK_SHIFT)
         }
     }
 
-    fun start() {
-        timer = Timer()
-        timer?.schedule(timerTask, 0L, 60 * 1000L)
-    }
-
-    fun stop() = timer?.cancel()
+    fun start() = timer.schedule(task, 0L, 60 * 1000L)
+    fun stop() = task.cancel()
 }