content: package net.minecraft.block;
  
  import net.minecraft.block.material.Material;
  import net.minecraft.block.state.IBlockState;
  import net.minecraft.creativetab.CreativeTabs;
  import net.minecraft.entity.item.EntityFallingBlock;
  import net.minecraft.init.Blocks;
  import net.minecraft.util.BlockPos;
  import net.minecraft.world.World;
  
  import java.util.Random;
  
  public class BlockFalling extends Block {
      public static boolean fallInstantly;
  
      public BlockFalling() {
          super(Material.sand);
          this.setCreativeTab(CreativeTabs.tabBlock);
      }
  
      public BlockFalling(Material materialIn) {
          super(materialIn);
      }
  
      public void onBlockAdded(World worldIn, BlockPos pos, IBlockState state) {
          worldIn.scheduleUpdate(pos, this, this.tickRate(worldIn));
      }
  
      public void onNeighborBlockChange(World worldIn, BlockPos pos, IBlockState state, Block neighborBlock) {
          worldIn.scheduleUpdate(pos, this, this.tickRate(worldIn));
      }
  
      public void updateTick(World worldIn, BlockPos pos, IBlockState state, Random rand) {
          if (!worldIn.isRemote) {
              this.checkFallable(worldIn, pos);
          }
      }
  
      private void checkFallable(World worldIn, BlockPos pos) {
          if (canFallInto(worldIn, pos.down()) && pos.getY() >= 0) {
              int i = 32;
  
              if (!fallInstantly && worldIn.isAreaLoaded(pos.add(-i, -i, -i), pos.add(i, i, i))) {
                  if (!worldIn.isRemote) {
                      EntityFallingBlock entityfallingblock = new EntityFallingBlock(worldIn, (double) pos.getX() + 0.5D, pos.getY(), (double) pos.getZ() + 0.5D, worldIn.getBlockState(pos));
                      this.onStartFalling(entityfallingblock);
                      worldIn.spawnEntityInWorld(entityfallingblock);
                  }
              } else {
                  worldIn.setBlockToAir(pos);
                  BlockPos blockpos;
  
                  for (blockpos = pos.down(); canFallInto(worldIn, blockpos) && blockpos.getY() > 0; blockpos = blockpos.down()) {
                  }
  
                  if (blockpos.getY() > 0) {
                      worldIn.setBlockState(blockpos.up(), this.getDefaultState());
                  }
              }
          }
      }
  
      protected void onStartFalling(EntityFallingBlock fallingEntity) {
      }
  
      public int tickRate(World worldIn) {
          return 2;
      }
  
      public static boolean canFallInto(World worldIn, BlockPos pos) {
          Block block = worldIn.getBlockState(pos).getBlock();
          Material material = block.blockMaterial;
          return block == Blocks.fire || material == Material.air || material == Material.water || material == Material.lava;
      }
  
      public void onEndFalling(World worldIn, BlockPos pos) {
      }
  }
  