MultiLineLabel.java Source code

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Here is the source code for MultiLineLabel.java

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/*
 This file is part of the BlueJ program. 
 Copyright (C) 1999-2009  Michael Klling and John Rosenberg 
     
 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 2 
 of the License, or (at your option) 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, write to the Free Software 
 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA. 
     
 This file is subject to the Classpath exception as provided in the  
 LICENSE.txt file that accompanied this code.
 */

import java.awt.Color;
import java.awt.Component;
import java.awt.Font;
import java.util.ArrayList;
import java.util.List;

import javax.swing.Box;
import javax.swing.BoxLayout;
import javax.swing.JLabel;
import javax.swing.JPanel;

/**
 ** @version $Id: MultiLineLabel.java 6164 2009-02-19 18:11:32Z polle $
 ** @author Justin Tan
 ** A multi-line Label-like AWT component.
 **/
public class MultiLineLabel extends JPanel {
    protected int fontAttributes = Font.PLAIN;
    protected float alignment;
    protected Color col = null;
    protected int spacing = 0;

    /**
     ** Constructor - make a multiline label
     **/
    public MultiLineLabel(String text, float alignment) {
        this.alignment = alignment;
        setLayout(new BoxLayout(this, BoxLayout.Y_AXIS));
        if (text != null)
            setText(text);
    }

    /**
     ** Constructor, defaults to centered text
     **/
    public MultiLineLabel(String text) {
        this(text, LEFT_ALIGNMENT);
    }

    /**
     * Constructor, empty with the given alignment
     */
    public MultiLineLabel(float alignment) {
        this(null, alignment);
    }

    /**
     * Constructor, empty with the given alignment and line spacing
     */
    public MultiLineLabel(float alignment, int spacing) {
        this(null, alignment);
        this.spacing = spacing;
    }

    /**
     ** Constructor - make an empty multiline label
     **/
    public MultiLineLabel() {
        this(null, LEFT_ALIGNMENT);
    }

    public void setText(String text) {
        // clear the existing lines from the panel
        removeAll();
        addText(text);
    }

    public void addText(String text) {
        addText(text, 12);
    }

    public void addText(String text, int size) {
        if (spacing > 0)
            add(Box.createVerticalStrut(spacing));

        String strs[] = splitLines(text);
        JLabel l;
        Font font = new Font("SansSerif", fontAttributes, size);

        for (int i = 0; strs != null && i < strs.length; i++) {
            l = new JLabel(strs[i]);
            l.setFont(font);
            l.setAlignmentX(alignment);

            if (col != null)
                l.setForeground(col);

            add(l);
        }
    }

    /**
     * Splits "string" by "Delimiter"
     * 
     * @param str - the string to be split
     * @param delimiter - the field delimiter within str
     * @returns an array of Strings
     */
    public static String[] split(String str, String delimiter) {
        List<String> strings = new ArrayList<String>();
        int start = 0;
        int len = str.length();
        int dlen = delimiter.length();
        int offset = str.lastIndexOf(delimiter); // First of all, find the
        // Last occurance of the Delimiter
        // Stop empty delimiters
        if (dlen < 1)
            return null;
        else if (offset < 0) // one element
        {
            String[] result = { str };
            return result;
        }

        //
        // Append the delimiter onto the end if it doesn't already exit
        //
        if (len > offset + dlen) {
            str += delimiter;
            len += dlen;
        }

        do {
            // Get the new Offset
            offset = str.indexOf(delimiter, start);
            strings.add(str.substring(start, offset));

            // Get the new Start position
            start = offset + dlen;
        } while ((start < len) && (offset != -1));

        // Convert the list into an Array of Strings
        String result[] = new String[strings.size()];
        strings.toArray(result);
        return result;
    }

    /**
     * Splits "string" into lines (stripping end-of-line characters)
     * 
     * @param str - the string to be split
     * @returns an array of Strings
     */
    public static String[] splitLines(String str) {
        return (str == null ? null : split(str, "\n"));
    }

    public void addText(String text, boolean bold, boolean italic) {
        int oldAttributes = fontAttributes;
        setBold(bold);
        setItalic(italic);
        addText(text);
        fontAttributes = oldAttributes;
    }

    public void setForeground(Color col) {
        this.col = col;
        Component[] components = this.getComponents();
        for (int i = 0; i < components.length; i++) {
            Component component = components[i];
            component.setForeground(col);
        }
    }

    public void setItalic(boolean italic) {
        if (italic)
            fontAttributes |= Font.ITALIC;
        else
            fontAttributes &= ~Font.ITALIC;
    }

    public void setBold(boolean bold) {
        if (bold)
            fontAttributes |= Font.BOLD;
        else
            fontAttributes &= ~Font.BOLD;
    }
}