java - "Checkbox editor" for JTable -

what best way add "checkbox editor" jtable? far have jtable use custom abstracttablemodel , use 2 collections data: 1 hashmap add each row checkbox "false" value. second collection framework simple arraylist integers. abstracttablemodel has custom method delete selected rows arraylist , abstracttablemodel. problem if "check" chceckbox in table, checked value stays in same row. think problem in overriding setvalueat. piece of code:

package checkboxeditor;  import java.awt.borderlayout; import javax.swing.jframe; import javax.swing.jpanel; import javax.swing.jscrollpane; import javax.swing.jtable; import javax.swing.table.abstracttablemodel; import java.awt.event.actionevent; import java.awt.event.actionlistener; import java.util.arraylist; import java.util.hashmap; import javax.swing.jbutton;  public class checkboxeditor extends jpanel {      public checkboxeditor() {         super(new borderlayout());          mytablemodel mytablemodel = new mytablemodel();         jtable table = new jtable(mytablemodel);         table.setfillsviewportheight(true);          jbutton deletebtn = new jbutton("delete selected rows");         deletebtn.addactionlistener(new actionlistener() {             @override             public void actionperformed(actionevent ae) {                 int rowcount = table.getrowcount();                 (int = rowcount - 1; >= 0; i--) {                     boolean checked = (boolean) table.getvalueat(i, 0);                     if (checked) {                         mytablemodel.removerow((int) table.getvalueat(i, 1));                     }                 }             }         });         add(deletebtn, borderlayout.page_start);          //create scroll pane , add table it.         jscrollpane scrollpane = new jscrollpane(table);          //add scroll pane panel.         add(scrollpane, borderlayout.center);     }      class mytablemodel extends abstracttablemodel {          // column names         private string[] columnnames = {"#", "number"};         // check boxes         hashmap<integer, boolean> checkboxes = new hashmap();         // data         arraylist<integer> data = new arraylist();          public mytablemodel() {             (integer = 1; < 6; i++) {                 data.add(i);             }          }          public void removerow(integer numbertodelete) {             int index = data.indexof(numbertodelete);             data.remove(numbertodelete);             firetablerowsdeleted(index, index);         }          public int getcolumncount() {             return columnnames.length;         }          public int getrowcount() {             return data.size();         }          public string getcolumnname(int col) {             return columnnames[col];         }          public object getvalueat(int row, int col) {             switch (col) {                 case 0:                     object value = checkboxes.get(row);                     return (value == null) ? false : value;                 case 1:                     return data.get(row);                 default:                     return "";             }         }          /*          * jtable uses method determine default renderer/          * editor each cell.  if didn't implement method,          * last column contain text ("true"/"false"),          * rather check box.          */         public class getcolumnclass(int col) {             switch (col) {                 case 0:                     return boolean.class;                 default:                     return integer.class;             }         }          /*          * don't need implement method unless table's          * editable.          */         public boolean iscelleditable(int row, int col) {             //note data/cell address constant,             //no matter cell appears onscreen.             return (col == 0);         }          /*          * don't need implement method unless table's          * data can change.          */         public void setvalueat(object value, int row, int col) {             if (col == 0) {                 checkboxes.put(row, (boolean) value);             }         }      }      /**      * create gui , show it. thread safety, method should      * invoked event-dispatching thread.      */     private static void createandshowgui() {         //create , set window.         jframe frame = new jframe("tabledemo");         frame.setdefaultcloseoperation(jframe.exit_on_close);          //create , set content pane.         checkboxeditor newcontentpane = new checkboxeditor();         newcontentpane.setopaque(true); //content panes must opaque         frame.setcontentpane(newcontentpane);          //display window.         frame.pack();         frame.setvisible(true);     }      public static void main(string[] args) {         //schedule job event-dispatching thread:         //creating , showing application's gui.         javax.swing.swingutilities.invokelater(new runnable() {             public void run() {                 createandshowgui();             }         });     } } 

one hashmap add each row checkbox "false" value. second collection framework simple arraylist integers

there no need 2 data structure or create custom tablemodel.

you can use defaulttablemodel. defaulttablemodel allows store type of object in each row. need override getcolumnclass(...) method of model return proper class , table choose appropriate renderer/editor column. like:

string[] columnnames = {"#", "number"}; defaulttablemodel model = new defaulttablemodel(columnnames, 0) {     //  returning class of each column allow different     //  renderers , editors used based on class      public class getcolumnclass(int column)     {         return column == 0 ? boolean.class : integer.class;     } };  jtable table = new jtable(model); 

then can add data table doing like:

for (integer = 1; < 6; i++)  {     object[] row = {boolean.false, i};     model.addrow( row); }  

the defaulttablemodel supports methods removing rows model.