ArrayList Hashmap Null Pointer Exception

Question

I am getting NullPointerException in the last statement.Please help.

ArrayList<HashMap<String, String>> contactList;
for(int i=0; i < jsonArray.length(); i++){
    JSONObject jsonObject = jsonArray.getJSONObject(i);
    HashMap<String,String> contact = new HashMap<String,String>();
    contact.put(TAG_ID, jsonObject.optString("id").toString());
    contact.put(TAG_NAME,jsonObject.optString("name").toString());
    contact.put(TAG_EXT,jsonObject.optString("extension").toString());
    contactList.add(contact);
}

Possible duplicate of [What is a Null Pointer Exception, and how do I fix it?](http://stackoverflow.com/questions/218384/what-is-a-null-pointer-exception-and-how-do-i-fix-it) — Dhaval Patel, Jan 22 '16 at 06:39

score 1 · Answer 1 · answered Jan 22 '16 at 06:40

1

you have not initialize contactList.

 ArrayList<HashMap<String, String>> contactList = new ArrayList<HashMap<String, String>>();

answered Jan 22 '16 at 06:40

nikk

407
3
7

score 0 · Answer 2 · answered Jan 22 '16 at 06:38

0

you have not initialize contactList, it should be initialized before use

ArrayList<HashMap<String, String>> contactList=new ArrayList<HashMap<String, String>>();

answered Jan 22 '16 at 06:38

Ravi

34,851
21
122
183

score 0 · Answer 3 · answered Jan 22 '16 at 06:40

ArrayList should be iitialized first. Try this,

ArrayList<HashMap<String, String>> contactList;
 ArrayList<HashMap<String, String>> contactList=new ArrayList<HashMap<String, String>>();
 for(int i=0; i < jsonArray.length(); i++){
 JSONObject jsonObject = jsonArray.getJSONObject(i);
 HashMap<String,String> contact = new HashMap<String,String>();
 contact.put(TAG_ID, jsonObject.optString("id").toString());
 contact.put(TAG_NAME,jsonObject.optString("name").toString());
 contact.put(TAG_EXT,jsonObject.optString("extension").toString());
 contactList.add(contact);
}

score 0 · Accepted Answer · answered Jan 22 '16 at 06:45

You have to initialize contactList `

ArrayList<HashMap<String, String>> contactList=new ArrayList<HashMap<String, String>>();
 for(int i=0; i < jsonArray.length(); i++){
 JSONObject jsonObject = jsonArray.getJSONObject(i);
 HashMap<String,String> contact = new HashMap<String,String>();
 contact.put(TAG_ID, jsonObject.optString("id").toString());
 contact.put(TAG_NAME,jsonObject.optString("name").toString());
 contact.put(TAG_EXT,jsonObject.optString("extension").toString());
 contactList.add(contact);
}`

ArrayList Hashmap Null Pointer Exception

4 Answers4