Question

I have a HashMap. The key will be a string and value can be anything ranging from a variable to a ArrayList.

The problem is I have an ArrayList. The values stored in the ArrayList are Region1,Region2,Region3,Region4.

So when I put this ArrayList in HashMap and print the HashMap I get the output as
[Region1,Region2,Region3,Region4].

Problem is I need to insert this whole comma separated String in Db and my procedure cannot recognize [] in this output.

How can I solve it..I cannot change anything at DB end.
Here’s the code snippet:-

ArrayList<String> Region=new ArrayList<String>();
        Region.add("Region1");
        Region.add("Region2");
        Region.add("Region3");
        System.out.println(Region);

Output is [Region1, Region2, Region3]

I put this ArrayList in HashMap

HashMap<String,Object> regionHashMap=new HashMap<String,Object>();
        regionHashMap.put("regionssss", Region);
        System.out.println(regionHashMap);

Output is {regionssss=[Region1, Region2, Region3]}.

How can i Remove [] from the ArrayList…

I already succedded by using StringBuffer and Iterator but I cannot use it everytime Since I have huge number of ArrayList which will go inside the HashMap..

Answer 1

The String representation of a List automatically encloses with “[ ]” characters.
You could either create your own ‘toString’ method:

private String listToString(List<?> l) {
    StringBuilder sb = new StringBuilder();
    for (int i = 0; i < l.size(); i++) {
        sb.append(l.get(i));
        if (i != l.size() -1) sb.append(", ");
    }
    return sb.toString();
}

Or, you could use the substring function to remove the braces:

String s = list.toString();
s = s.substring(1, s.length()-1);