Created course parser as a subclass of file parser

- refactored file parser as an abstract class
- created course parser to parse course xml file

#implement #fix #refactor #story[9] #story[10]

src/main/java/seng302/models/parsers/CourseParser.java

@@ -0,0 +1,126 @@
+package seng302.models.parsers;
+
+import org.w3c.dom.*;
+import seng302.models.GateMark;
+import seng302.models.Mark;
+
+import java.util.ArrayList;
+import java.util.NoSuchElementException;
+
+/**
+ * parse a course xml file
+ * Created by Haoming Yin (hyi25) on 16/3/2017
+ */
+public class CourseParser extends FileParser {
+
+	private Document doc;
+
+	public CourseParser(String path) {
+		super(path);
+		this.doc = this.parseFile();
+	}
+
+	/**
+	 * create a mark by given node
+	 *
+	 * @param node
+	 * @return a mark, or null if fails to create a mark
+	 */
+	private Mark generateMark(Node node) {
+		try {
+			if (node.getNodeType() == Node.ELEMENT_NODE) {
+				Element element = (Element) node;
+				String name = element.getElementsByTagName("name").item(0).getTextContent();
+				double lat = Double.valueOf(element.getElementsByTagName("latitude").item(0).getTextContent());
+				double lon = Double.valueOf(element.getElementsByTagName("longitude").item(0).getTextContent());
+				Mark mark = new Mark(name, lat, lon);
+				return mark;
+			} else {
+				throw new NoSuchElementException("Cannot generate a mark by given node.");
+			}
+		} catch (Exception e) {
+			e.printStackTrace();
+			return null;
+		}
+	}
+
+	/**
+	 * generate an arrayList of gates
+	 *
+	 * @return an arrayList of gates, or null if no gate has been found.
+	 */
+	public ArrayList<GateMark> getGates() {
+		ArrayList<GateMark> gateMarks = new ArrayList<>();
+
+		try {
+			NodeList nodes = doc.getElementsByTagName("gate");
+
+			for (int i = 0; i < nodes.getLength(); i++) {
+				Node node = nodes.item(i);
+
+				if (node.getNodeType() == Node.ELEMENT_NODE) {
+					Element element = (Element) node;
+					String name = element.getElementsByTagName("name").item(0).getTextContent();
+					Mark mark1 = generateMark(element.getElementsByTagName("mark").item(0));
+					Mark mark2 = generateMark(element.getElementsByTagName("mark").item(1));
+					GateMark gateMark = new GateMark(name, mark1, mark2);
+					gateMarks.add(gateMark);
+				}
+			}
+		} catch (Exception e) {
+			e.printStackTrace();
+		}
+		return gateMarks;
+	}
+
+	/**
+	 * generate an arrayList of marks
+	 *
+	 * @return an arrayList of marks, or null if no gate has been found.
+	 */
+	public ArrayList<Mark> getMarks() {
+		ArrayList<Mark> marks = new ArrayList<>();
+
+		try {
+			// find the "marks" tag
+			Node node = doc.getElementsByTagName("marks").item(0);
+			// iterate all "marks"'s children
+			for (Node n = node.getFirstChild(); n != null; n = n.getNextSibling()) {
+				// if node's tag name is "mark"
+				if (n.getNodeType() == Node.ELEMENT_NODE) {
+					Element element = (Element) n;
+					if (element.getNodeName() == "mark") {
+						marks.add(generateMark(n));
+					}
+				}
+			}
+			return marks;
+		} catch (Exception e) {
+			e.printStackTrace();
+			return null;
+		}
+	}
+
+	/**
+	 * return the order of all the marks along a course
+	 *
+	 * @return an arrayList of the names of ordered course marks
+	 */
+	public ArrayList<String> getOrder() {
+		ArrayList<String> markOrder = new ArrayList<>();
+
+		try {
+			Node orderNode = doc.getElementsByTagName("order").item(0);
+			for (Node node = orderNode.getFirstChild(); node != null; node = node.getNextSibling()) {
+				if (node.getNodeType() == Node.ELEMENT_NODE) {
+					Element element = (Element) node;
+					String name = element.getTextContent();
+					markOrder.add(name);
+				}
+			}
+		} catch (Exception e) {
+			e.printStackTrace();
+		}
+		return markOrder;
+	}
+}

src/main/java/seng302/models/parsers/FileParser.java

@@ -0,0 +1,35 @@
+package seng302.models.parsers;
+
+import org.w3c.dom.*;
+import javax.xml.parsers.*;
+import java.io.*;
+
+/**
+ *
+ *
+ * Created by Haoming Yin (hyi25) on 16/3/2017
+ */
+public abstract class FileParser {
+
+	private String filePath;
+
+	public FileParser(String path) {
+		this.filePath = path;
+	}
+
+	protected Document parseFile () {
+		try {
+			File file = new File(this.filePath);
+			DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
+			DocumentBuilder builder = factory.newDocumentBuilder();
+			Document doc = builder.parse(file);
+			// optional, in order to recover info from broken line.
+			doc.getDocumentElement().normalize();
+			return doc;
+		} catch (Exception e) {
+			e.printStackTrace();
+			return null;
+		}
+
+	}
+}