Overview

• This lab requires that you install or set up some infrastructure for using the course software. Follow the "setup" portion of this lab right by class on Thursday.
  If there is a problem, we can resolve it quickly and get you underway

Setup

• Follow the instructions for 131 students to install eclipse and the svn plugin.
• Look at what the 131 students do in their Lab 0 to get an idea of how to check out your repo.
• Check out your repo using hte following URL:

  https://shell.cec.wustl.edu:8443/cse531_fl11/svn/Lastname-StudentID
  

  Respond to the challenge with your WUSTL key and password.
• Try to run the Hello class in the hello package.

Background

1. Rob's description of the patterns used in this software can be found here
2. Documentation for the software can be found here.
   1. In the Package Explorer, look at the project present in your workspace after you have accessed it via svn.

      Eclipse, in its eagerness, has probably already tried to compile your project, but there are some things it won't find yet.

      Silly eclipse.

      So don't worry about problems just yet.
   2. In some of the files for this lab, there are references to classes that are in the jar file you downloaded. We must make eclipse aware of this:
      1. Click on the CSE531-lastname-id in the Package Explorer
      2. Click File→Properties
      3. Click Java Build Path
      4. Select the Libraries tab
      5. Click Add External JARs…
      6. Add the hw1.jar file to the list by browsing for the location at which you stored the file.
   3. At this point, or shortly thereafter, all the red flags should go away, as eclipse recompiles the code with the jar file now present.
   4. Open the demos/HydraDom.java file from the Package Explorer.
   5. Right-click the HydraDom.java entry in the Package Explorer, and go down to Run as → Java Application and let it go. You should see output in the Console window.
3. What you should see in the output:
   • For each of two examples, the application builds the DFST, runs my solution to the dominators problem, and then runs yours. Yours doesn't do anything yet, so the idom fields are null in the last graph listing.
   • The first example provided is the one from class, so you should be able to debug with it. The second example is a 3-node example where node 1 should dominate nodes 2 and 3. You are asked to make that example more interesting before turning in your solution.

Assignment

• You are to implement the Tarjan-Lengauer Dominators algorithm in the PCESGraph/CSE531DomTree.java file, and that is the only file you will submit. You are to complete the computeIdom method, but you will probably want to write some private helper methods.
• You are to fill in the PCESGraph.CSE531DomTree.genMyGraph method with a more interesting and unique graph -- at least 10 nodes, at least 15 edges, and verify that your solution works on that graph as well.
• Commit your solution to your repository so it can be graded.

Notes:

• Given a Vertex v, you can get the DirectedVertex corresponding to v by:

    DirectedVertex dirV = DirectedGraph.getDirectedVertex(v);
  

• Given a Vertex v, you can get its DomVertex by
  • The private method DomTree.getLocalDom(v)
  • Do not use the static method getDomVertex -- it does not seem to work and I'm looking into that.
  and you can put the DomVertex's fields to good use in your algorithm, as there are fields there to hold the semidominator, etc.