Putting a HashMap inside a HashMap then populating the two maps.

Question

I have to write a script for sql inserts. I have all the information that I need in order to write the inserts but there are three different pieces of information that I'm using and not just two. I know that I have to put a Map inside a Map but I am getting a compile error when I try to put anything into the maps.

HashMap<String,String> acctyp = new HashMap<String,String>();
HashMap<String, HashMap<String,String>> gens = new HashMap<String,HashMap<String,String>>();
gens.put("'GEN01'", acctyp.put("'Open'","ACCTYP 01"));
gens.put("'GEN02'", acctyp.put("'Sheltered'","ACCTYP 02"));
gens.put("'GEN03'", acctyp.put("'Spousal sheltered'","ACCTYP 03"));
gens.put("'GEN06'", acctyp.put("'Education'","ACCTYP 06"));
gens.put("'GEN12'", acctyp.put("'Non-ded. sheltered'","ACCTYP 12"));
gens.put("'GEN30'", acctyp.put("'Structured Product'","ACCTYP 30"));
gens.put("'GEN31'", acctyp.put("'Emergency Cash'","ACCTYP 31"));
gens.put("'GEN85'", acctyp.put("'Insurance Savings'","ACCTYP 85"));
gens.put("'GEN86'", acctyp.put("'Stock Option'","ACCTYP 86"));
gens.put("'GEN94'", acctyp.put("'Business Other'","ACCTYP 94"));
gens.put("'GEN95'", acctyp.put("'Personal use'","ACCTYP 95"));
gens.put("'GEN97'", acctyp.put("'Universal Life'","ACCTYP 97"));

If anyone has any insight of why I'm getting a compile error on the puts then it would be greatly appreciated.

Solution 1

Map.put returns a string. gens is mapping String to HashMap. You are calling gens.put(string, string) and should instead be calling gens.put(string, HashMap<string,string>)

Your code should read:

HashMap<String,String> acctyp = new HashMap<String,String>();
HashMap<String, HashMap<String,String>> gens = new HashMap<String,HashMap<String,String>>();
acctyp.put("'Open'","ACCTYP 01");
gens.put("'GEN01'", acctyp);

Solution 2

Because Map#put() returns a String value. When you do this : acctyp.put("'Open'","ACCTYP 01") , it actually returns a String hence gens.put("'GEN01'", acctyp.put("'Open'","ACCTYP 01")); is a compilation error.

What I suppose you want is :

HashMap<String,String> acctyp = new HashMap<String,String>();
HashMap<String, HashMap<String,String>> gens = new 
HashMap<String,HashMap<String,String>>();
acctyp.put("'Open'","ACCTYP 01");
acctyp.put("'Sheltered'","ACCTYP 02");
acctyp.put("'Spousal sheltered'","ACCTYP 03");
gens.put("'GEN01'", acctype);

Solution 3

Your code should like this

        HashMap<String, HashMap<String,String>> gens = new HashMap<String,HashMap<String,String>>();
        HashMap<String,String> acctyp =  new HashMap<String,String>();
        acctyp.put("'Open'","ACCTYP 01");
        gens.put("'GEN01'", acctyp);
        acctyp =  new HashMap<String,String>();
        acctyp.put("'Sheltered'","ACCTYP 02");
        gens.put("'GEN02'", acctyp);
        acctyp =  new HashMap<String,String>();
        acctyp.put("'Spousal sheltered'","ACCTYP 03");
        gens.put("'GEN03'",acctyp );
        acctyp =  new HashMap<String,String>();
        acctyp.put("'Education'","ACCTYP 06");
        gens.put("'GEN06'",acctyp );            
        acctyp =  new HashMap<String,String>();
        acctyp.put("'Non-ded. sheltered'","ACCTYP 12");
        gens.put("'GEN06'",acctyp );
        acctyp =  new HashMap<String,String>();
        acctyp.put("'Structured Product'","ACCTYP 30");
        gens.put("'GEN06'",acctyp );

        acctyp =  new HashMap<String,String>();
        acctyp.put("'Emergency Cash'","ACCTYP 31");
        gens.put("'GEN06'",acctyp );

Solution 4

You can also write this code if you want to fill the second hashmap later on:

acctype.put("'Open'",new Hashmap<String,String>()); 
acctype.put("''Sheltered'",new Hashmap<String,String>());
... So on
actttype.get("'Open'").put("'Sheltered'","ACCTYP 02")
acttype.get("'Sheltered'").put("'Spousal sheltered'","ACCTYP 03")
and so on ...

hope that helps too

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