I don't usually give code but anyway when I do I add comments.. It's your loss if you copy and paste without trying to understand so please don't if you're serious about modding.
@Override
public void breakBlock(World world, int x, int y, int z, Block block, int meta)
{
//Using random ints in the drops may cause a crash. Set amounts don't.
//Loops through all drops.
for(int i = 0; i < block.getDrops(world, x, y, z, meta, 0).size(); i++){
//Breaks the loop if i == size.
if(i == block.getDrops(world, x, y, z, meta, 0).size()){
break;
}
//Spawns the drops into the world.
world.spawnEntityInWorld(new EntityItem(world, x, y, z, block.getDrops(world, x, y, z, meta, 0).get(i)));
}
//Sets the block to the current block.
world.setBlock(x, y, z, this);
}