Example from Eclipse ^

• public class ToolBarManager extends ContributionManager implements IToolBarManager {

	public void update(boolean force) {

		//	long startTime= 0;
		//	if (DEBUG) {
		//		dumpStatistics();
		//		startTime= (new Date()).getTime();
		//	}

		if (isDirty() || force) {

			if (toolBarExist()) {

				int oldCount = toolBar.getItemCount();

				// clean contains all active items without double separators
				IContributionItem[] items = getItems();
				ArrayList clean = new ArrayList(items.length);
				IContributionItem separator = null;
				//			long cleanStartTime= 0;
				//			if (DEBUG) {
				//				cleanStartTime= (new Date()).getTime();
				//			}
				for (int i = 0; i < items.length; ++i) {
					IContributionItem ci = items[i];
					if (!ci.isVisible()) {
						continue;
					}
					if (ci.isSeparator()) {
						// delay creation until necessary
						// (handles both adjacent separators, and separator at
						// end)
						separator = ci;
					} else {
						if (separator != null) {
							if (clean.size() > 0) {
								clean.add(separator);
							}
							separator = null;
						}
						clean.add(ci);
					}
				}
				//			if (DEBUG) {
				//				System.out.println(" Time needed to build clean vector: " +
				// ((new Date()).getTime() - cleanStartTime));
				//			}

				// determine obsolete items (removed or non active)
				ToolItem[] mi = toolBar.getItems();
				ArrayList toRemove = new ArrayList(mi.length);
				for (int i = 0; i < mi.length; i++) {
					Object data = mi[i].getData();
					if (data == null
							|| !clean.contains(data)
							|| (data instanceof IContributionItem && ((IContributionItem) data)
									.isDynamic())) {
						toRemove.add(mi[i]);
					}
				}

				// Turn redraw off if the number of items to be added
				// is above a certain threshold, to minimize flicker,
				// otherwise the toolbar can be seen to redraw after each item.
				// Do this before any modifications are made.
				// We assume each contribution item will contribute at least one
				// toolbar item.
				boolean useRedraw = (clean.size() - (mi.length - toRemove
						.size())) >= 3;
                try {
                    if (useRedraw) {
                        toolBar.setRedraw(false);
                    }

                    // remove obsolete items
                    for (int i = toRemove.size(); --i >= 0;) {
                        ToolItem item = (ToolItem) toRemove.get(i);
                        if (!item.isDisposed()) {
                            Control ctrl = item.getControl();
                            if (ctrl != null) {
                                item.setControl(null);
                                ctrl.dispose();
                            }
                            item.dispose();
                        }
                    }

                    // add new items
                    IContributionItem src, dest;
                    mi = toolBar.getItems();
                    int srcIx = 0;
                    int destIx = 0;
                    for (Iterator e = clean.iterator(); e.hasNext();) {
                        src = (IContributionItem) e.next();

                        // get corresponding item in SWT widget
                        if (srcIx < mi.length) {
							dest = (IContributionItem) mi[srcIx].getData();
						} else {
							dest = null;
						}

                        if (dest != null && src.equals(dest)) {
                            srcIx++;
                            destIx++;
                            continue;
                        }

                        if (dest != null && dest.isSeparator()
                                && src.isSeparator()) {
                            mi[srcIx].setData(src);
                            srcIx++;
                            destIx++;
                            continue;
                        }

                        int start = toolBar.getItemCount();
                        src.fill(toolBar, destIx);
                        int newItems = toolBar.getItemCount() - start;
                        for (int i = 0; i < newItems; i++) {
                            ToolItem item = toolBar.getItem(destIx++);
                            item.setData(src);
                        }
                    }

                    // remove any old tool items not accounted for
                    for (int i = mi.length; --i >= srcIx;) {
                        ToolItem item = mi[i];
                        if (!item.isDisposed()) {
                            Control ctrl = item.getControl();
                            if (ctrl != null) {
                                item.setControl(null);
                                ctrl.dispose();
                            }
                            item.dispose();
                        }
                    }

                    setDirty(false);

                    // turn redraw back on if we turned it off above
                } finally {
                    if (useRedraw) {
                        toolBar.setRedraw(true);
                    }
                }

				int newCount = toolBar.getItemCount();
				relayout(toolBar, oldCount, newCount);
			}

		}

		//	if (DEBUG) {
		//		System.out.println(" Time needed for update: " + ((new
		// Date()).getTime() - startTime));
		//		System.out.println();
		//	}
	}

Redundant boolean logic:

if (!check_part(baz)) then
  # do something
end

def check_part(foo)
  if (foo) then
    return true
  else
    return false
  end
end


# why not just write this:
unless baz
  # do something
end

nicely split code...

def is_valid_time_format(str)
  if(!is_day_valid(str))
    return false
  end

  if(!is_month_valid(str))
    return false
  end

  if(!is_date_valid(str))
    return false
  end

  if(!is_year_valid(str))
    return false
  end

  if(!is_time_valid(str))
    return false
  end

  return true
end