javax.swing.text: public class: DocumentFilter

javax.swing.text
public class: DocumentFilter [javadoc | source]

java.lang.Object
   javax.swing.text.DocumentFilter

Direct Known Subclasses:
Filter, DefaultDocumentFilter

DocumentFilter, as the name implies, is a filter for the Document mutation methods. When a Document containing a DocumentFilter is modified (either through insert or remove), it forwards the appropriate method invocation to the DocumentFilter. The default implementation allows the modification to occur. Subclasses can filter the modifications by conditionally invoking methods on the superclass, or invoking the necessary methods on the passed in FilterBypass. Subclasses should NOT call back into the Document for the modification instead call into the superclass or the FilterBypass.

When remove or insertString is invoked on the DocumentFilter, the DocumentFilter may callback into the FilterBypass multiple times, or for different regions, but it should not callback into the FilterBypass after returning from the remove or insertString method.

By default, text related document mutation methods such as insertString, replace and remove in AbstractDocument use DocumentFilter when available, and Element related mutation methods such as create, insert and removeElement in DefaultStyledDocument do not use DocumentFilter. If a method doesn't follow these defaults, this must be explicitly stated in the method documentation.

Also see:

javax.swing.text.Document

javax.swing.text.AbstractDocument

javax.swing.text.DefaultStyledDocument

since: 1.4 -

Nested Class Summary:
abstract public static class	DocumentFilter.FilterBypass	Used as a way to circumvent calling back into the Document to change it. Document implementations that wish to support a DocumentFilter must provide an implementation that will not callback into the DocumentFilter when the following methods are invoked from the DocumentFilter.

Method from javax.swing.text.DocumentFilter Summary:
insertString, remove, replace

Methods from java.lang.Object:
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method from javax.swing.text.DocumentFilter Detail:
public void insertString(FilterBypass fb, int offset, String string, AttributeSet attr) throws BadLocationException { fb.insertString(offset, string, attr); } Invoked prior to insertion of text into the specified Document. Subclasses that want to conditionally allow insertion should override this and only call supers implementation as necessary, or call directly into the FilterBypass.
public void remove(FilterBypass fb, int offset, int length) throws BadLocationException { fb.remove(offset, length); } Invoked prior to removal of the specified region in the specified Document. Subclasses that want to conditionally allow removal should override this and only call supers implementation as necessary, or call directly into the `FilterBypass` as necessary.
public void replace(FilterBypass fb, int offset, int length, String text, AttributeSet attrs) throws BadLocationException { fb.replace(offset, length, text, attrs); } Invoked prior to replacing a region of text in the specified Document. Subclasses that want to conditionally allow replace should override this and only call supers implementation as necessary, or call directly into the FilterBypass.

Method from javax.swing.text.DocumentFilter Detail:

 public  void insertString(FilterBypass fb,
    int offset,
    String string,
    AttributeSet attr) throws BadLocationException {
        fb.insertString(offset, string, attr);
}

Invoked prior to insertion of text into the specified Document. Subclasses that want to conditionally allow insertion should override this and only call supers implementation as necessary, or call directly into the FilterBypass.

 public  void remove(FilterBypass fb,
    int offset,
    int length) throws BadLocationException {
        fb.remove(offset, length);
}

FilterBypass

 public  void replace(FilterBypass fb,
    int offset,
    int length,
    String text,
    AttributeSet attrs) throws BadLocationException {
        fb.replace(offset, length, text, attrs);
}

Invoked prior to replacing a region of text in the specified Document. Subclasses that want to conditionally allow replace should override this and only call supers implementation as necessary, or call directly into the FilterBypass.