content: package net.minecraft.block;
  
  import net.minecraft.block.material.Material;
  import net.minecraft.block.state.IBlockState;
  import net.minecraft.util.AxisAlignedBB;
  import net.minecraft.util.BlockPos;
  import net.minecraft.world.World;
  
  import java.util.IdentityHashMap;
  import java.util.Map;
  
  public class BlockAir extends Block {
      private static final Map mapOriginalOpacity = new IdentityHashMap();
  
      protected BlockAir() {
          super(Material.air);
      }
  
      public int getRenderType() {
          return -1;
      }
  
      public AxisAlignedBB getCollisionBoundingBox(World worldIn, BlockPos pos, IBlockState state) {
          return null;
      }
  
      public boolean isOpaqueCube() {
          return false;
      }
  
      public boolean canCollideCheck(IBlockState state, boolean hitIfLiquid) {
          return false;
      }
  
      public void dropBlockAsItemWithChance(World worldIn, BlockPos pos, IBlockState state, float chance, int fortune) {
      }
  
      public boolean isReplaceable(World worldIn, BlockPos pos) {
          return true;
      }
  
      public static void setLightOpacity(Block p_setLightOpacity_0_, int p_setLightOpacity_1_) {
          if (!mapOriginalOpacity.containsKey(p_setLightOpacity_0_)) {
              mapOriginalOpacity.put(p_setLightOpacity_0_, Integer.valueOf(p_setLightOpacity_0_.lightOpacity));
          }
  
          p_setLightOpacity_0_.lightOpacity = p_setLightOpacity_1_;
      }
  
      public static void restoreLightOpacity(Block p_restoreLightOpacity_0_) {
          if (mapOriginalOpacity.containsKey(p_restoreLightOpacity_0_)) {
              int i = ((Integer) mapOriginalOpacity.get(p_restoreLightOpacity_0_)).intValue();
              setLightOpacity(p_restoreLightOpacity_0_, i);
          }
      }
  }
  