I can't launch my world.

What I expected to happen was to launch my world.

What actually happened was a crush that said java has not have enough memory.

Steps to Reproduce:
1. I launch Minecraft.
2. I went to single player to create a world.
3. I create a superflat world with 1 block of grass on top then 5 dirt then 230 stone and last 1 bedrock.