From 286f82a5c5a5b1636ba9cc7ca9693eafa7d9f41f Mon Sep 17 00:00:00 2001
From: Dmitry Jemerov <yole@jetbrains.com>
Date: Wed, 31 May 2017 16:00:05 +0200
Subject: [PATCH] Don't set java.awt.headless if it was set externally

---
 compiler/cli/src/org/jetbrains/kotlin/cli/common/CLITool.kt | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/compiler/cli/src/org/jetbrains/kotlin/cli/common/CLITool.kt b/compiler/cli/src/org/jetbrains/kotlin/cli/common/CLITool.kt
index e717a99d989..d0e54b0b5b2 100644
--- a/compiler/cli/src/org/jetbrains/kotlin/cli/common/CLITool.kt
+++ b/compiler/cli/src/org/jetbrains/kotlin/cli/common/CLITool.kt
@@ -158,7 +158,9 @@ abstract class CLITool<A : CommonToolArguments> {
         fun doMain(compiler: CLITool<*>, args: Array<String>) {
             // We depend on swing (indirectly through PSI or something), so we want to declare headless mode,
             // to avoid accidentally starting the UI thread
-            System.setProperty("java.awt.headless", "true")
+            if (System.getProperty("java.awt.headless") == null) {
+                System.setProperty("java.awt.headless", "true")
+            }
             val exitCode = doMainNoExit(compiler, args)
             if (exitCode != ExitCode.OK) {
                 System.exit(exitCode.code)