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| − | ==[http://www.cs.umd.edu/%7Emeesh/cmsc420/spr07/part1/p11/node20.html Using the provided XML processing code to get a working parser]==
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| − | === Node -> Element ===
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| − | <blockquote>
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| − | In the DOM, every XML object implements the org.w3c.dom.Node interface. Nodes have a lot of useful methods, but the ones you care most about are getNodeName(), getNodeValue(), and getAttribute(). Suppose you had a Node object representing one of our command elements. You could determine which command it was with the following code:
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| − | <code><pre>
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| − | Node command = ...;
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| − | if (command.getNodeName().equals("createCity"))
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| − | // createCity command
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| − | </pre></code>
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| − | To get the value of an attribute, you could use this code:
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| − | <code><pre>
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| − | String name = command.getAttribute("name");
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| − | </pre></code>
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| − | </blockquote>
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| − | If you read the Java API, you'll see both Document and Element are subtypes of Node. A Node does not have the method getAttribute(). But Element does have a getAttribute() method.
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| − | === Node Child List ===
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| − | <blockquote>
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| − | To ignore comment nodes, you can even do an instanceof check of the command node to make sure it is of type Element.
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| − | </blockquote>
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| − | instanceof checks can be costly. If there's an alternative, you should use it. That said, Node has a method called [http://java.sun.com/j2se/1.5.0/docs/api/org/w3c/dom/Node.html#getNodeType() getNodeType()].
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| − | == [http://www.cs.umd.edu/%7Emeesh/cmsc420/spr07/part1/p11/node22.html Outputting XML Conventions] ==
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| − | === Printing to System.out ===
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| − | <blockquote>
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| − | It is sufficient to merely spit these out to System.out (the standard output stream) as they are discovered when processing the commands. However, remember that the result must be a well-formed XML document and a well-formed XML document must have a single root element.
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| − | </blockquote>
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| − | Do not call System.out.println() to print out your output. Instead, create a new Document and append Elements to it as you process commands. You can print a Document to System.out using XmlUtility.print().
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| − | == [http://www.cs.umd.edu/%7Emeesh/cmsc420/spr07/part1/p11/node24.html Drawing a spatial map using CanvasPlus] ==
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| − | === Color class ===
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| − | It should be noted that all colors used in CanvasPlus refer to their java.awt.Color counterparts.
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| − | == [http://www.cs.umd.edu/%7Emeesh/cmsc420/spr07/part1/p11/node26.html Input] ==
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| − | === spatialWidth and spatialHeight ===
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| − | <blockquote>
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| − | The attributes are spatialWidth and spatialHeight, both Unrestricted Integers...
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| − | </blockquote>
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| − | spatialWidth and spatialHeight will always be 2<sup>k</sup> by 2<sup>k</sup>. That way you can take advantage of bit operators.
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| − |
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| − | === List cities ===
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| − | <blockquote>
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| − | listCities
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| − | Prints all cities (vertices) currently present in the graph.
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| − | </blockquote>
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| − | Graph here means data dictionary.
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| − | === Nearest City tie ===
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| − | <blockquote>
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| − | nearestCity
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| − | Will return the name and location of the closest city to the specified point in space. To do this correctly, you may want to use the PriorityQueue-otherwise, you might not be fast enough.
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| − | </blockquote>
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| − | If there is a distance tie, check the city names using java.lang.String.compareTo() (for a distance tie, the nearestCity name is less than the other city name).
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