i have question from programming pearls

problem is following

show how  to use  lomuto's partitioning scheme to sort varying length bit strings in time proportional to the sum oof their length 

and algorithm is following

each record in x[0..n-1] has an integer length and pointer to the array bit[0..length-1] code

 void bsort(l,u,depth){

    if (l>=u)
  return;
 for (int i=l;i<u;i++)
   if (x[i].length<depth)
  swap(i,l++);
m=l;
 if (x[i].bit[depth] ==0)
 swap(i,m++);
 bsort(l,m-1,depth+1);
bsort(m,u,depth+1);

please help me i need following things 1. how this algorith works 2.how implement in java?