I m trying to make that if palyer enters my dimension he will start to take damageunless he is on creative mode or wearing spacesuit but it damages me even if im wearing on and i dot know why

My if statement in entityplayer:

if (this.dimension == 20 && this.capabilities.isCreativeMode && !ModMechanics.isPlayerWearingSpaceSuit(this))
    {
       	this.attackEntityFrom(DamageSource.generic, 2);	
    }

ModMechanics:

package skyinf;

import java.util.Random;

import net.minecraft.client.Minecraft;
import net.minecraft.entity.player.EntityPlayer;
import net.minecraft.item.ItemStack;

public class ModMechanics {
/**Checks if player if wearing a Space Suit**/
public static boolean isPlayerWearingSpaceSuit(EntityPlayer thePlayer)
{
	ItemStack helmet = thePlayer.getCurrentArmor(3);
	ItemStack torso = thePlayer.getCurrentArmor(2);
	ItemStack legs = thePlayer.getCurrentArmor(1);
	ItemStack boots = thePlayer.getCurrentArmor(0);
	ItemStack sSH = (new ItemStack(ModBase.sSH));
	ItemStack sST = (new ItemStack(ModBase.sST));
	ItemStack sSL = (new ItemStack(ModBase.sSL));
	ItemStack sSB = (new ItemStack(ModBase.sSB));   
	if (helmet == sSH && torso == sST && legs == sSL && boots == sSB)
	{
		return true;
	}
	else
	{
		return false;
	}

}
}

My if is good, i tested it by removing that isPlayerWearingSpaceSuit condition

You if code says creative mode AND !isPlayerWearingSpaceSuit

You most likely need it to be an or (|| instead of &&)