Java JTextComponent Delete deleteLine(JTextComponent textComponent)

Description

delete Line

License

Open Source License

Declaration

public static void deleteLine(JTextComponent textComponent) 

Method Source Code

//package com.java2s;
/*/*from   w  w w  .j  a  v  a2  s  .  com*/
 * TextUtilities.java
 *
 * Copyright (C) 2002-2015 Takis Diakoumis
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 3
 * of the License, or any later version.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 *
 */

import javax.swing.text.JTextComponent;

public class Main {
    public static void deleteLine(JTextComponent textComponent) {
        char newLine = '\n';
        String _newLine = "\n";
        int caretIndex = textComponent.getCaretPosition();

        String text = textComponent.getText();
        StringBuilder sb = new StringBuilder(text);

        int endOfLineIndexBefore = -1;
        int endOfLineIndexAfter = sb.indexOf(_newLine, caretIndex);

        char[] textChars = text.toCharArray();

        for (int i = 0; i < textChars.length; i++) {

            if (i >= caretIndex) {
                break;
            } else {

                if (textChars[i] == newLine)
                    endOfLineIndexBefore = i;

            }

        }

        if (endOfLineIndexBefore == -1) {
            endOfLineIndexBefore = 0;
        }

        if (endOfLineIndexAfter == -1) {
            sb.delete(endOfLineIndexBefore, sb.length());
        } else if (endOfLineIndexBefore == -1) {
            sb.delete(0, endOfLineIndexAfter + 1);
        } else if (endOfLineIndexBefore == 0 && endOfLineIndexAfter == 0) {
            sb.deleteCharAt(0);
        } else {
            sb.delete(endOfLineIndexBefore, endOfLineIndexAfter);
        }

        textComponent.setText(sb.toString());

        if (endOfLineIndexBefore + 1 > sb.length()) {

            textComponent.setCaretPosition(endOfLineIndexBefore == -1 ? 0 : endOfLineIndexBefore);

        } else {

            textComponent.setCaretPosition(endOfLineIndexBefore + 1);
        }

    }
}

Related

1. appendText(JTextComponent fld, String s, String delimiter)
2. delete(JTextComponent textComponent)
3. deleteSelection(JTextComponent textComponent)
4. deleteWord(JTextComponent textComponent)
5. modelToView(final JTextComponent scrollableComponent, int pos)