Compiler Daemon: Use clearHandlersCache() method instead of Reflection API

(old code may fail in IDEA Ultimate due to field obfuscation)

compiler/daemon/src/org/jetbrains/kotlin/daemon/CompileServiceImpl.kt

@@ -17,6 +17,7 @@
 package org.jetbrains.kotlin.daemon
 
 import com.intellij.openapi.vfs.impl.ZipHandler
+import com.intellij.openapi.vfs.impl.jar.CoreJarFileSystem
 import org.jetbrains.kotlin.cli.common.CLICompiler
 import org.jetbrains.kotlin.cli.common.ExitCode
 import org.jetbrains.kotlin.cli.common.KOTLIN_COMPILER_ENVIRONMENT_KEEPALIVE_PROPERTY
@@ -39,7 +40,8 @@ import java.util.concurrent.atomic.AtomicInteger
 import java.util.concurrent.locks.ReentrantReadWriteLock
 import java.util.logging.Level
 import java.util.logging.Logger
-import kotlin.comparisons.*
+import kotlin.comparisons.compareBy
+import kotlin.comparisons.reversed
 import kotlin.concurrent.read
 import kotlin.concurrent.schedule
 import kotlin.concurrent.write
@@ -486,28 +488,7 @@ class CompileServiceImpl(
 
     private fun clearJarCache() {
         ZipHandler.clearFileAccessorCache()
-        val classloader = javaClass.classLoader
-        // TODO: replace the following code with direct call to CoreJarFileSystem.<clearCache> as soon as it will be available (hopefully in 15.02)
-        try {
-            KotlinCoreEnvironment.applicationEnvironment?.jarFileSystem.let { jarfs ->
-                val jarfsClass = classloader.loadClass("com.intellij.openapi.vfs.impl.jar.CoreJarFileSystem")
-                val privateHandlersField = jarfsClass.getDeclaredField("myHandlers")
-                privateHandlersField.isAccessible = true
-                privateHandlersField.get(jarfs)?.let {
-                    val clearMethod = privateHandlersField.type.getMethod("clear")
-                    if (clearMethod != null) {
-                        clearMethod.invoke(it)
-                        log.info("successfully cleared com.intellij.openapi.vfs.impl.jar.CoreJarFileSystem.myHandlers")
-                    }
-                    else {
-                        log.info("unable to access com.intellij.openapi.vfs.impl.jar.CoreJarFileSystem.myHandlers.clear")
-                    }
-                } ?: log.info("unable to access CoreJarFileSystem.myHandlers (${privateHandlersField.get(jarfs)})")
-            }
-        }
-        catch (e: Exception) {
-            log.log(Level.SEVERE, "error clearing CoreJarFileSystem", e)
-        }
+        (KotlinCoreEnvironment.applicationEnvironment?.jarFileSystem as? CoreJarFileSystem)?.clearHandlersCache()
     }
 
     // copied (with edit) from gradle plugin