This Document restricts the size of the contained plain text to the given number of characters.
/*
* JCommon : a free general purpose class library for the Java(tm) platform
*
*
* (C) Copyright 2000-2005, by Object Refinery Limited and Contributors.
*
* Project Info: http://www.jfree.org/jcommon/index.html
*
* This library is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation; either version 2.1 of the License, or
* (at your option) any later version.
*
* This library is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
* License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
* USA.
*
* [Java is a trademark or registered trademark of Sun Microsystems, Inc.
* in the United States and other countries.]
*
* ---------------------------
* LengthLimitingDocument.java
* ---------------------------
* (C)opyright 2003, 2004, by Thomas Morgner and Contributors.
*
* Original Author: Thomas Morgner;
* Contributor(s): David Gilbert (for Object Refinery Limited);
*
* $Id: LengthLimitingDocument.java,v 1.3 2005/10/18 13:18:34 mungady Exp $
*
* Changes
* -------
* 22-Jan-2003 : Initial version
* 05-Feb-2003 : Documentation
*
*/
import javax.swing.text.AttributeSet;
import javax.swing.text.BadLocationException;
import javax.swing.text.PlainDocument;
/**
* This Document restricts the size of the contained plain text to the given number of
* characters.
*
* @author Thomas Morgner
*/
public class LengthLimitingDocument extends PlainDocument {
/** The maximum length. */
private int maxlen;
/**
* Creates a new LengthLimitingDocument, with no limitation.
*/
public LengthLimitingDocument() {
this(-1);
}
/**
* Creates a new LengthLimitingDocument with the given limitation. No more than
* maxlen characters can be added to the document. If maxlen is negative, then
* no length check is performed.
*
* @param maxlen the maximum number of elements in this document
*/
public LengthLimitingDocument(final int maxlen) {
super();
this.maxlen = maxlen;
}
/**
* Sets the maximum number of characters for this document. Existing characters
* are not removed.
*
* @param maxlen the maximum number of characters in this document.
*/
public void setMaxLength(final int maxlen) {
this.maxlen = maxlen;
}
/**
* Returns the defined maximum number characters for this document.
* @return the maximum number of characters
*/
public int getMaxLength() {
return this.maxlen;
}
/**
* Inserts the string into the document. If the length of the document would
* violate the maximum characters restriction, then the string is cut down so
* that
* @param offs the offset, where the string should be inserted into the document
* @param str the string that should be inserted
* @param a the attribute set assigned for the document
* @throws javax.swing.text.BadLocationException if the offset is not correct
*/
public void insertString(final int offs, final String str, final AttributeSet a)
throws BadLocationException {
if (str == null) {
return;
}
if (this.maxlen < 0) {
super.insertString(offs, str, a);
}
final char[] numeric = str.toCharArray();
final StringBuffer b = new StringBuffer();
b.append(numeric, 0, Math.min(this.maxlen, numeric.length));
super.insertString(offs, b.toString(), a);
}
}
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