Exception in thread "main" java.lang.NullPointerException (JDBC) -


exception in thread "main" java.lang.nullpointerexception @ gui.cataloguepanel.(cataloguepanel.java)

i'm trying initialize bookquery object in cataloguepanel , call getbooklist()

cataloguepanel.java

package gui;  import java.util.arraylist;  import backend.book; import backend.bookquery;  // catalog panel. shows library titles' information , allows users place orders. public class cataloguepanel extends jpanel implements gbpanel {      bookquery bquery;     arraylist<book> booklist = bquery.getbooklist(); // here's error occurred  }

edit: http://www.reactionface.info/sites/default/files/imagecache/node_page/images/1314029819767.png

bookquery bquery; arraylist<book> booklist = bquery.getbooklist();

bquery not initialized, similer null.getbooklist() must produce nullpointerexception. either initialize bquery. -

bookquery bquery= new bookquery();

or make getbooklist() method static , call method -

arraylist<book> booklist = bookquery.getbooklist();

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