Question

I found this problem so interesting. I am using an awk 2D array that has a key,value,count of the same. and that is being printed to a file. This file is in the below format

A100|B100|3
A100|C100|2
A100|B100|5

Now I have a file like this .. My motive is to convert this file into a hash map so that the final output from the hash map is.

A100|B100|8
A100|C100|2

Just an aggregation

The challenge is, this one has 3 dimensions and not two. I did have an another file in the below format which is

D100|4
H100|5
D100|6

I easily aggregated the above as it is only 2D and I used the below code to do that

String[] fields= strLine.trim().split("\\|");
if(hashmap.containsKey(fields[0]))
{
//Update the value of the key here
hashmap.put(fields[0],hashmap.get(fields[0]) + Integer.parseInt(fields[1]));
}
else
{
//Inserting the key to the map
hashmap.put(fields[0],Integer.parseInt(fields[1]));
}

So this was quite simple for implementation.

But when it comes to 3D I have to have an another check inside.. My idea for this is to maintain a [B100,5(beanObject[5])]

  Map<String,beanClassObject> hashmap=new Map<String,beanClassObject>();

secongField hash map which has been used in the code that has a mapping relation between the created ben Object subscript and the key as the second field “For instance it is “

This bean class would have the getter and setter method for the 2nd and 3rd fields of the file. I hope I am clear with this point. So the implementation of this would be

if(hashmap.containsKey(fields[0]))
{
   **//Have to check whether the the particular key value pair already exists ... I dint find any method for this ... Just a normal iteration is there .. Could you ppl guide me regarding this**

    //Update the value of the key here
     secondFieldHashMap.get(fields[1]).COunt= secondFieldHashMap.get(fields[1]).getCOunt+ Integer.parseInt(fields[2]));
   }
   else
    {
     //Inserting the key to the map
     hashmap.put(fields[0],Integer.parseInt(fields[1]));
     secondFieldHashMap.get(fields[1]).COunt=  Integer.parseInt(fields[2]));
    }
else
{

 // This meands there is no key field
 // Hence insert the key field and also update the count of seconfFieldHashMap as done previously.
 }

COuld you ppl please throw some ideas regarding this. Thank you

Answer 1

Consider using a Table available in the Google Guava libraries.