Module java.desktop
Package javax.swing

Class RowFilter<M,I>

java.lang.Object
javax.swing.RowFilter<M,I>
Type Parameters:
M - the type of the model; for example PersonModel
I - the type of the identifier; when using TableRowSorter this will be Integer

public abstract class RowFilter<M,I> extends Object
RowFilter is used to filter out entries from the model so that they are not shown in the view. For example, a RowFilter associated with a JTable might only allow rows that contain a column with a specific string. The meaning of entry depends on the component type. For example, when a filter is associated with a JTable, an entry corresponds to a row; when associated with a JTree, an entry corresponds to a node.

Subclasses must override the include method to indicate whether the entry should be shown in the view. The Entry argument can be used to obtain the values in each of the columns in that entry. The following example shows an include method that allows only entries containing one or more values starting with the string "a":

 RowFilter<Object,Object> startsWithAFilter = new RowFilter<Object,Object>() {
   public boolean include(Entry<? extends Object, ? extends Object> entry) {
     for (int i = entry.getValueCount() - 1; i >= 0; i--) {
       if (entry.getStringValue(i).startsWith("a")) {
         // The value starts with "a", include it
         return true;
       }
     }
     // None of the columns start with "a"; return false so that this
     // entry is not shown
     return false;
   }
 };
 
RowFilter has two formal type parameters that allow you to create a RowFilter for a specific model. For example, the following assumes a specific model that is wrapping objects of type Person. Only Persons with an age over 20 will be shown:
 RowFilter<PersonModel,Integer> ageFilter = new RowFilter<PersonModel,Integer>() {
   public boolean include(Entry<? extends PersonModel, ? extends Integer> entry) {
     PersonModel personModel = entry.getModel();
     Person person = personModel.getPerson(entry.getIdentifier());
     if (person.getAge() > 20) {
       // Returning true indicates this row should be shown.
       return true;
     }
     // Age is <= 20, don't show it.
     return false;
   }
 };
 PersonModel model = createPersonModel();
 TableRowSorter<PersonModel> sorter = new TableRowSorter<PersonModel>(model);
 sorter.setRowFilter(ageFilter);
 
Since:
1.6
See Also: