From 93d6e6d422dbabadc56fa48c58441974f07a8ce9 Mon Sep 17 00:00:00 2001
From: md_5 <git@md-5.net>
Date: Fri, 14 Dec 2018 10:32:52 +1100
Subject: BUILDTOOLS-431: Detect and warn about low memory. Seems to occur on
 32 bit Java installs.

---
 src/main/java/org/spigotmc/builder/Bootstrap.java | 13 ++++++++++++-
 src/main/java/org/spigotmc/builder/Builder.java   | 13 ++++++++++++-
 2 files changed, 24 insertions(+), 2 deletions(-)

diff --git a/src/main/java/org/spigotmc/builder/Bootstrap.java b/src/main/java/org/spigotmc/builder/Bootstrap.java
index 57a2b78..2a1ceba 100644
--- a/src/main/java/org/spigotmc/builder/Bootstrap.java
+++ b/src/main/java/org/spigotmc/builder/Bootstrap.java
@@ -1,5 +1,7 @@
 package org.spigotmc.builder;
 
+import com.google.common.base.Joiner;
+
 public class Bootstrap
 {
 
@@ -11,7 +13,7 @@ public class Bootstrap
         {
             System.err.println( "Outdated Java detected (" + javaVersion + "). BuildTools requires at least Java 7. Please update Java and try again." );
             System.err.println( "You may use java -version to double check your Java version." );
-            return;
+            System.exit( 1 );
         }
 
         if ( javaVersion.getVersion() < JavaVersion.JAVA_8.getVersion() )
@@ -26,6 +28,15 @@ public class Bootstrap
             System.err.println( "*** WARNING *** You may use java -version to double check your Java version." );
         }
 
+        long memoryMb = Runtime.getRuntime().maxMemory() >> 20;
+        if ( memoryMb < 512 )
+        {
+            System.err.println( "BuildTools requires at least 512M of memory to run (1024M recommended), but has only detected " + memoryMb + "M." );
+            System.err.println( "This can often occur if you are running a 32-bit system, or one with low RAM." );
+            System.err.println( "Please re-run BuildTools with manually specified memory, e.g: java -Xmx1024M -jar BuildTools.jar " + Joiner.on( ' ' ).join( args ) );
+            System.exit( 1 );
+        }
+
         Builder.main( args );
     }
 }
diff --git a/src/main/java/org/spigotmc/builder/Builder.java b/src/main/java/org/spigotmc/builder/Builder.java
index 8a5953e..82bb069 100644
--- a/src/main/java/org/spigotmc/builder/Builder.java
+++ b/src/main/java/org/spigotmc/builder/Builder.java
@@ -30,6 +30,7 @@ import java.io.InputStream;
 import java.io.InputStreamReader;
 import java.io.OutputStream;
 import java.io.PrintStream;
+import java.lang.management.ManagementFactory;
 import java.net.URI;
 import java.net.URL;
 import java.net.URLConnection;
@@ -669,7 +670,17 @@ public class Builder
         }
         if ( !pb.environment().containsKey( "_JAVA_OPTIONS" ) )
         {
-            pb.environment().put( "_JAVA_OPTIONS", "-Djdk.net.URLClassPath.disableClassPathURLCheck=true" );
+            String javaOptions = "-Djdk.net.URLClassPath.disableClassPathURLCheck=true";
+
+            for ( String arg : ManagementFactory.getRuntimeMXBean().getInputArguments() )
+            {
+                if ( arg.startsWith( "-Xmx" ) )
+                {
+                    javaOptions += " " + arg;
+                }
+            }
+
+            pb.environment().put( "_JAVA_OPTIONS", javaOptions );
         }
         if ( msysDir != null )
         {
-- 
cgit v1.2.3