BgcLabelProvider.java

package edu.ualberta.med.biobank.gui.common.widgets;

import java.util.Enumeration;
import java.util.Vector;

import org.eclipse.jface.viewers.ITableLabelProvider;
import org.eclipse.jface.viewers.LabelProvider;
import org.eclipse.swt.graphics.Image;

public abstract class BgcLabelProvider extends LabelProvider implements
    ITableLabelProvider {

    @Override
    public abstract String getColumnText(Object element, int columnIndex);

    @Override
    public Image getColumnImage(Object element, int columnIndex) {
        return null;
    }

    /**
     * This function takes a string value and a line length, and returns an
     * array of lines. Lines are cut on word boundaries, where the word boundary
     * is a space character. Spaces are included as the last character of a
     * word, so most lines will actually end with a space. This isn't too
     * problematic, but will cause a word to wrap if that space pushes it past
     * the max line length.
     * 
     * @param text
     * @param len
     * @return
     */
    public static String[] wrapText(String text, int len) {
        // return empty array for null text
        if (text == null)
            return new String[] {};

        // return text if len is zero or less
        if (len <= 0)
            return new String[] { text };

        // return text if less than length
        if (text.length() <= len)
            return new String[] { text };

        char[] chars = text.toCharArray();
        Vector<String> lines = new Vector<String>();
        StringBuffer line = new StringBuffer();
        StringBuffer word = new StringBuffer();

        for (int i = 0; i < chars.length; i++) {
            word.append(chars[i]);

            if (chars[i] == ' ') {
                if ((line.length() + word.length()) > len) {
                    lines.add(line.toString());
                    line.delete(0, line.length());
                }

                line.append(word);
                word.delete(0, word.length());
            }
        }

        // handle any extra chars in current word
        if (word.length() > 0) {
            if ((line.length() + word.length()) > len) {
                lines.add(line.toString());
                line.delete(0, line.length());
            }
            line.append(word);
        }

        // handle extra line
        if (line.length() > 0) {
            lines.add(line.toString());
        }

        String[] ret = new String[lines.size()];
        int c = 0; // counter
        for (Enumeration<String> e = lines.elements(); e.hasMoreElements(); c++) {
            ret[c] = e.nextElement();
        }

        return ret;
    }

}