setblockstate throws java.util.ConcurrentModificationException

[OldManMorris]

Any ideas? I'm stumped.

 

 Here's the code snippet:

 

 private static void buildSchematic() {

        // scan the structure and output blocks to world
        for (int ix = 0; ix < width; ++ix) {

            for (int iy = 0; iy < height; ++iy) {

                for (int iz = 0; iz < length; ++iz) {

                    // locate the block to be loaded at this position
                    int index = getIndex(ix, iy, iz);
                    // get the block using the id
                    Block blox = Block.getBlockById(blocks[index]);

                    // set the block position in the world
                    BlockPos pos = new BlockPos(player.posX + ix, player.posY + iy, player.posZ + iz);

                    // get blockstate
                    IBlockState iblockstate = world.getBlockState(pos);
                    // set the block
                    world.setBlockState(pos, blox.getDefaultState());
                    System.out.println("blox:" + blox + "/" + (player.posX + ix) + "/" + (player.posY + iy) + "/"
                            + (player.posZ + iz));

                }
            }
        }

 

The loop and its calling method complete then comes this:

Here's the error:

 

[14:37:40] [Server thread/INFO]: Stopping server
[14:37:40] [Server thread/INFO]: Saving players
[14:37:40] [Server thread/INFO]: Player755 lost connection: TextComponent{text='Server closed', siblings=[], style=Style{hasParent=false, color=null, bold=null, italic=null, underlined=null, obfuscated=null, clickEvent=null, hoverEvent=null, insertion=null}}
[14:37:40] [Server thread/INFO]: Player755 left the game
[14:37:40] [Server thread/INFO]: Stopping singleplayer server as player logged out
[14:37:40] [Server thread/INFO]: Saving worlds
[14:37:40] [Server thread/INFO]: Saving chunks for level 'New World'/Overworld
[14:37:41] [Server thread/INFO]: Saving chunks for level 'New World'/Nether
[14:37:41] [Server thread/INFO]: Saving chunks for level 'New World'/The End
[14:37:41] [Server thread/INFO] [FML]: Unloading dimension 0
[14:37:41] [Server thread/INFO] [FML]: Unloading dimension -1
[14:37:41] [Server thread/INFO] [FML]: Unloading dimension 1
[14:37:41] [Server thread/INFO] [FML]: Applying holder lookups
[14:37:41] [Server thread/INFO] [FML]: Holder lookups applied
[14:37:42] [Client thread/FATAL]: Unreported exception thrown!
java.util.ConcurrentModificationException
    at java.util.HashMap$HashIterator.nextNode(Unknown Source) ~[?:1.8.0_131]
    at java.util.HashMap$KeyIterator.next(Unknown Source) ~[?:1.8.0_131]
    at net.minecraft.client.renderer.RenderGlobal.updateClouds(RenderGlobal.java:1208) ~[RenderGlobal.class:?]
    at net.minecraft.client.Minecraft.runTick(Minecraft.java:1869) ~[Minecraft.class:?]
    at net.minecraft.client.Minecraft.runGameLoop(Minecraft.java:1119) ~[Minecraft.class:?]
    at net.minecraft.client.Minecraft.run(Minecraft.java:407) [Minecraft.class:?]
    at net.minecraft.client.main.Main.main(Main.java:118) [Main.class:?]
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_131]
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_131]
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_131]
    at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_131]
    at net.minecraft.launchwrapper.Launch.launch(Launch.java:135) [launchwrapper-1.12.jar:?]
    at net.minecraft.launchwrapper.Launch.main(Launch.java:28) [launchwrapper-1.12.jar:?]
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_131]
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_131]
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_131]
    at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_131]
    at net.minecraftforge.gradle.GradleStartCommon.launch(GradleStartCommon.java:97) [start/:?]
    at GradleStart.main(GradleStart.java:26) [start/:?]
[14:37:42] [Client thread/INFO] [STDOUT]: [net.minecraft.init.Bootstrap:printToSYSOUT:600]: ---- Minecraft Crash Report ----
// Quite honestly, I wouldn't worry myself about that.

Time: 6/24/17 2:37 PM
Description: Unexpected error

java.util.ConcurrentModificationException
    at java.util.HashMap$HashIterator.nextNode(Unknown Source)
    at java.util.HashMap$KeyIterator.next(Unknown Source)
    at net.minecraft.client.renderer.RenderGlobal.updateClouds(RenderGlobal.java:1208)
    at net.minecraft.client.Minecraft.runTick(Minecraft.java:1869)
    at net.minecraft.client.Minecraft.runGameLoop(Minecraft.java:1119)
    at net.minecraft.client.Minecraft.run(Minecraft.java:407)
    at net.minecraft.client.main.Main.main(Main.java:118)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at net.minecraft.launchwrapper.Launch.launch(Launch.java:135)
    at net.minecraft.launchwrapper.Launch.main(Launch.java:28)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at net.minecraftforge.gradle.GradleStartCommon.launch(GradleStartCommon.java:97)
    at GradleStart.main(GradleStart.java:26)

A detailed walkthrough of the error, its code path and all known details is as follows:
---------------------------------------------------------------------------------------

-- Head --
Thread: Client thread
Stacktrace:
    at java.util.HashMap$HashIterator.nextNode(Unknown Source)
    at java.util.HashMap$KeyIterator.next(Unknown Source)
    at net.minecraft.client.renderer.RenderGlobal.updateClouds(RenderGlobal.java:1208)

-- Affected level --
Details:
    Level name: MpServer
    All players: 1 total; [EntityPlayerSP['Player755'/122, l='MpServer', x=-355.50, y=4.00, z=-1744.50]]
    Chunk stats: MultiplayerChunkCache: 552, 552
    Level seed: 0
    Level generator: ID 01 - flat, ver 0. Features enabled: false
    Level generator options: 
    Level spawn location: World: (-349,4,-1735), Chunk: (at 3,0,9 in -22,-109; contains blocks -352,0,-1744 to -337,255,-1729), Region: (-1,-4; contains chunks -32,-128 to -1,-97, blocks -512,0,-2048 to -1,255,-1537)
    Level time: 3159 game time, 3159 day time
    Level dimension: 0
    Level storage version: 0x00000 - Unknown?
    Level weather: Rain time: 0 (now: false), thunder time: 0 (now: false)
    Level game mode: Game mode: creative (ID 1). Hardcore: false. Cheats: false
    Forced entities: 40 total; [EntitySlime['Slime'/69, l='MpServer', x=-334.01, y=5.02, z=-1675.64], EntityPig['Pig'/83, l='MpServer', x=-309.50, y=4.00, z=-1784.50], EntityChicken['Chicken'/84, l='MpServer', x=-304.50, y=4.00, z=-1782.50], EntityChicken['Chicken'/85, l='MpServer', x=-306.12, y=4.00, z=-1779.88], EntitySlime['Slime'/87, l='MpServer', x=-306.89, y=4.00, z=-1667.13], EntitySlime['Slime'/24, l='MpServer', x=-426.28, y=4.00, z=-1782.61], EntitySlime['Slime'/89, l='MpServer', x=-309.71, y=5.17, z=-1666.27], EntityChicken['Chicken'/90, l='MpServer', x=-283.79, y=4.00, z=-1779.58], EntitySlime['Slime'/91, l='MpServer', x=-314.12, y=4.00, z=-1760.47], EntitySlime['Slime'/92, l='MpServer', x=-288.85, y=4.00, z=-1666.35], EntityChicken['Chicken'/29, l='MpServer', x=-433.50, y=4.00, z=-1668.50], EntitySlime['Slime'/93, l='MpServer', x=-304.78, y=4.00, z=-1665.81], EntitySlime['Slime'/94, l='MpServer', x=-304.38, y=4.00, z=-1683.90], EntitySlime['Slime'/21087, l='MpServer', x=-425.93, y=4.00, z=-1783.59], EntitySlime['Slime'/96, l='MpServer', x=-287.56, y=4.00, z=-1819.72], EntitySlime['Slime'/32, l='MpServer', x=-423.14, y=4.42, z=-1722.02], EntitySlime['Slime'/33, l='MpServer', x=-414.96, y=4.42, z=-1696.55], EntitySlime['Slime'/34, l='MpServer', x=-418.81, y=4.50, z=-1691.26], EntitySlime['Slime'/35, l='MpServer', x=-427.28, y=5.02, z=-1669.36], EntityChicken['Chicken'/36, l='MpServer', x=-436.07, y=4.00, z=-1672.07], EntitySlime['Slime'/100, l='MpServer', x=-276.76, y=5.25, z=-1787.53], EntitySlime['Slime'/38, l='MpServer', x=-418.15, y=4.00, z=-1677.09], EntitySlime['Slime'/102, l='MpServer', x=-280.27, y=4.42, z=-1749.22], EntitySlime['Slime'/39, l='MpServer', x=-409.50, y=4.00, z=-1687.00], EntitySlime['Slime'/8935, l='MpServer', x=-416.71, y=5.00, z=-1679.13], EntitySlime['Slime'/40, l='MpServer', x=-396.66, y=4.00, z=-1701.54], EntityPlayerSP['Player755'/122, l='MpServer', x=-355.50, y=4.00, z=-1744.50], EntitySlime['Slime'/41, l='MpServer', x=-386.88, y=4.00, z=-1704.53], EntitySlime['Slime'/42, l='MpServer', x=-379.03, y=5.18, z=-1702.83], EntitySlime['Slime'/58410, l='MpServer', x=-390.63, y=4.12, z=-1694.21], EntitySlime['Slime'/43, l='MpServer', x=-384.13, y=4.00, z=-1692.61], EntitySlime['Slime'/44, l='MpServer', x=-407.77, y=5.25, z=-1686.81], EntitySlime['Slime'/53548, l='MpServer', x=-301.66, y=4.00, z=-1670.17], EntitySlime['Slime'/45, l='MpServer', x=-383.15, y=4.00, z=-1695.91], EntitySlime['Slime'/23213, l='MpServer', x=-335.89, y=4.80, z=-1668.41], EntitySlime['Slime'/46, l='MpServer', x=-402.71, y=5.18, z=-1687.95], EntitySlime['Slime'/51, l='MpServer', x=-394.51, y=4.00, z=-1705.59], EntitySlime['Slime'/60, l='MpServer', x=-335.32, y=4.00, z=-1683.37], EntitySlime['Slime'/61, l='MpServer', x=-346.79, y=4.00, z=-1687.60], EntitySlime['Slime'/58430, l='MpServer', x=-279.85, y=4.00, z=-1814.84]]
    Retry entities: 0 total; []
    Server brand: fml,forge
    Server type: Integrated singleplayer server
Stacktrace:
    at net.minecraft.client.multiplayer.WorldClient.addWorldInfoToCrashReport(WorldClient.java:456)
    at net.minecraft.client.Minecraft.addGraphicsAndWorldToCrashReport(Minecraft.java:2774)
    at net.minecraft.client.Minecraft.run(Minecraft.java:436)
    at net.minecraft.client.main.Main.main(Main.java:118)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at net.minecraft.launchwrapper.Launch.launch(Launch.java:135)
    at net.minecraft.launchwrapper.Launch.main(Launch.java:28)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at net.minecraftforge.gradle.GradleStartCommon.launch(GradleStartCommon.java:97)
    at GradleStart.main(GradleStart.java:26)

-- System Details --
Details:
    Minecraft Version: 1.11.2
    Operating System: Windows 10 (amd64) version 10.0
    Java Version: 1.8.0_131, Oracle Corporation
    Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
    Memory: 561722968 bytes (535 MB) / 1038876672 bytes (990 MB) up to 1038876672 bytes (990 MB)
    JVM Flags: 3 total; -Xincgc -Xmx1024M -Xms1024M
    IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0
    FML: MCP 9.38 Powered by Forge 13.20.0.2228 5 mods loaded, 5 mods active
    States: 'U' = Unloaded 'L' = Loaded 'C' = Constructed 'H' = Pre-initialized 'I' = Initialized 'J' = Post-initialized 'A' = Available 'D' = Disabled 'E' = Errored
    UCHIJAAAA    minecraft{1.11.2} [Minecraft] (minecraft.jar) 
    UCHIJAAAA    mcp{9.19} [Minecraft Coder Pack] (minecraft.jar) 
    UCHIJAAAA    FML{8.0.99.99} [Forge Mod Loader] (forgeSrc-1.11.2-13.20.0.2228.jar) 
    UCHIJAAAA    forge{13.20.0.2228} [Minecraft Forge] (forgeSrc-1.11.2-13.20.0.2228.jar) 
    UCHIJAAAA    merlinsbuildings{1.0} [merlinsbuildings] (bin) 
    Loaded coremods (and transformers): 
    GL info: ' Vendor: 'Intel' Version: '4.4.0 - Build 21.20.16.4534' Renderer: 'Intel(R) HD Graphics 620'
    Launched Version: 1.11.2
    LWJGL: 2.9.4
    OpenGL: Intel(R) HD Graphics 620 GL version 4.4.0 - Build 21.20.16.4534, Intel
    GL Caps: Using GL 1.3 multitexturing.
Using GL 1.3 texture combiners.
Using framebuffer objects because OpenGL 3.0 is supported and separate blending is supported.
Shaders are available because OpenGL 2.1 is supported.
VBOs are available because OpenGL 1.5 is supported.

    Using VBOs: Yes
    Is Modded: Definitely; Client brand changed to 'fml,forge'
    Type: Client (map_client.txt)
    Resource Packs: 
    Current Language: English (US)
    Profiler Position: N/A (disabled)
    CPU: 4x Intel(R) Core(TM) i7-7500U CPU @ 2.70GHz
[14:37:42] [Client thread/INFO] [STDOUT]: [net.minecraft.init.Bootstrap:printToSYSOUT:600]: #@!@# Game crashed! Crash report saved to: #@!@# C:\Users\ericl\Desktop\Minecraft\Development-1.11.2\MerlinsBuildings\forge-1.11.2-13.20.0.2228-mdk\run\.\crash-reports\crash-2017-06-24_14.37.42-client.txt
AL lib: (EE) alc_cleanup: 1 device not closed
Java HotSpot(TM) 64-Bit Server VM warning: Using incremental CMS is deprecated and will likely be removed in a future release
 

[Draco18s]

And wrap that log in a spoiler tag. 

[OldManMorris]

You asked the perfect question. I was getting the client-side world: 

player = ClientProxy.getClientPlayer();
world = player.world;

 

When I shifted to client/server world, things worked just fine. I didn't realize there was a difference until now.

 

Thanks for the quick reply and assistance.