# Using the Visualiser

## Overview

The Visualiser is an extensible plugin that can be used to visualize anything that can be represented by bars and stripes. It began as the Aspect Visualiser, which was a part of the popular AJDT plugin. It was originally created to visualize how aspects were affecting classes in a project, but has since been extracted to become its own component.

The Visualiser plugin has two views - the main Visualiser view, which displays the bar drawing, and the Visualiser Menu, which displays the 'kinds' of stripes that appear on the bars. The Menu is used to activate and deactivate kinds, and to change the colours used. Bars in the Visualiser are given a white background if contain any stripes, otherwise they are dark grey.

## Visualization Modes

The data that the bars represent is structured as groups and members, where each group contains one or more members. Groups cannot contain other groups. In the AspectJ plugin, groups represent packages and members represent classes within that package. The Visualiser provides "Member View" where each bar represents a member, and "Group View" where each bar represensts a group. The size of any group is the sum of the sizes of all its members, and it can be considered to be a composition of all its members stacked on top of each other. Member and Group View can therefore be considered to be two diferent views on the same set of data.

Member View:

Group View:

Providers can choose to give Member and Group view different names and different icons. For example, AJDT describes Member View as "Class View" and Group View as "Package View" and gives them class and package icons accordingly. Whichever provider you are using, the farthest right button will be the Member View button, and the button just left of that will be the Group View button.

## Drawing Options

As well as Member and Group views, the Visualiser provides a variety of means of manipulating the bar drawing it produces.

- Deselect kinds

- Change the colours of kinds. (Click one of the buttons with a coloured square on to bring up a colour selection dialog for that kind).

- Limit to affected bars only

- Zoom in

- Fit to view, where the image is resized to fit the window or be the smallest it can after obeying certain minimums.

The 'Drawing Options' tab of the Visualiser preference page allows the user to further customise the view with preferred column width and stripe height settings and a selection of rendering styles.

## Quick-Select Actions

Several actions have been provided to enable quick selection and de-selection of kinds being shown. This is particularly useful for large data sets.

- Select All / Select None

  Selects (or deselects) all of the kinds in the Visualiser Menu.

- Only show..

  Right click on a bar, then click "Only show colors affecting this bar". This will activate all the kinds in the menu that affect the selected bar, and de-activate all the others.

## Providers

The Visualiser has a plug-in architecture where 'providers' register using the extension point provided. The Visualiser preferences page allows users to switch between providers.

To open the preference page click "Window" > "Preferences", then select "Visualiser" from the left hand menu. Alternatively click "Preferences" from the drop-down menu in the Visualiser view.

The Visualiser comes with three built-in providers:

- a simple file provider that reads bar and stripe infromation from two files
- a resources and markers provider that responds to selections in the workbench and displays files as bars, with associated markers as stripes,
- a JDT search results provider that displays Java classes as bars and the results of the most recent Java search as stripes.

To find out about writing your own provider for the Visualiser, see the "Writing a plug-in for the Visualiser" section of the Visualiser help.