Couchbase : 'java.io.File android.content.Context.getFilesDir()' on a null object reference -

i using couchbase store database locally on device. have saving database service class.

public void savetodatabase(string symbol, list<date> datelist, list<string> closelist){         cbdatabase db = new cbdatabase(db_name, this);          // create object contains data document         map<string, object> doccontent = new hashmap<>();         doccontent.put(symbol, symbol);         doccontent.put(date, datelist);         doccontent.put(close, closelist);         string docid = null;         try {             // 1. create             docid = db.create(doccontent);             assert(docid != null);             txt += ("created doc id " + docid + "\n");              txt += ("\n\nretrieve --> ");             // 2. retrieve             doccontent= db.retrieve(docid);             assert(doccontent != null);             txt += ("retrieved doc " + string.valueof(doccontent) + "\n");              txt += ("\n\ndelete --> ");             // 4. delete             boolean deleted = db.delete(docid);             assert(deleted == true);             txt += ("deleted document id: " + docid + "\n");              txt += ("\n\nsuccess.");         }         catch (exception e) {             // todo auto-generated catch block             e.printstacktrace();         } 

this cddatabase helper class using couchbase database don't understand might going new couchbase.

 public cbdatabase(string dbname, context context){          this.ctx = context;         /* manages access databases */         try {             manager = new manager( new androidcontext(ctx), manager.default_options );         }         catch (ioexception e) {             errorchecker.showexception(ctx, r.string.err_create_manager, e );             return;         }         // create name database , make sure name legal         // following characters valid:         // abcdefghijklmnopqrstuvwxyz0123456789_$()+-/         if ( ! manager.isvaliddatabasename(dbname)) {             errorchecker.showerror( ctx, r.string.err_db_name );             return;         }         // existing db name         // or create new 1 if doesn't exist         try {             database = manager.getdatabase(dbname);         }         catch (couchbaseliteexception e) {             errorchecker.showexception(ctx, r.string.err_no_db, e );             return;         }     } 

here logcat nullpointer

j

ava.lang.nullpointerexception: attempt invoke virtual method 'java.io.file android.content.context.getfilesdir()' on null object reference com.android.stockhawk w/system.err:     @ android.content.contextwrapper.getfilesdir(contextwrapper.java:203) com.android.stockhawk w/system.err:     @ com.couchbase.lite.android.androidcontext.getfilesdir(androidcontext.java:40) com.android.stockhawk w/system.err:     @ com.couchbase.lite.manager.<init>(manager.java:117) com.android.stockhawk w/system.err:     @ com.android.stockhawk.quotes.db.cbdatabase.<init>(cbdatabase.java:41) com.android.stockhawk w/system.err:     @ com.android.stockhawk.service.stocktaskservice.savetodatabase(stocktaskservice.java:191) com.android.stockhawk w/system.err:     @ com.android.stockhawk.service.stocktaskservice.getstockquotes(stocktaskservice.jcom.android.stockhawk w/system.err:     @ com.android.stockhawk.service.stocktaskservice.onruntask(stocktaskservice.java:141) com.android.stockhawk w/system.err:     @ com.android.stockhawk.service.stockintentservice.onhandleintent(stockintentservice.java:39)