Implement SVG pre-processing

src/parser/SvgParser.java

@@ -1,8 +1,11 @@
 package parser;
 
+import static parser.XmlUtil.asList;
+
 import java.io.File;
 import java.io.IOException;
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.List;
 import javax.xml.parsers.DocumentBuilder;
 import javax.xml.parsers.DocumentBuilderFactory;
@@ -25,17 +28,57 @@ public class SvgParser extends FileParser {
     shapes = new ArrayList<>();
   }
 
-  @Override
-  protected void parseFile(String path)
-      throws ParserConfigurationException, IOException, SAXException, IllegalArgumentException {
+  private Document getSvgDocument(String path)
+      throws IOException, SAXException, ParserConfigurationException {
+    // opens XML reader for svg file.
     DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
     factory.setValidating(true);
     factory.setIgnoringElementContentWhitespace(true);
     DocumentBuilder builder = factory.newDocumentBuilder();
     File file = new File(path);
-    Document doc = builder.parse(file);
 
-    for (Node elem : doc.getElementsByTagName("path"))
+    return builder.parse(file);
+  }
+
+  private String[] preProcessPath(String path) throws IllegalArgumentException {
+    // Replace all commas with spaces and then remove unnecessary whitespace
+    path = path.replace(',', ' ');
+    path = path.replaceAll("\\s+", " ");
+    path = path.replaceAll("(^\\s|\\s$)", "");
+
+    // If there are any characters in the path that are illegal
+    if (path.matches("[^mlhvcsqtazMLHVCSQTAZ\\-.\\d\\s]")) {
+      throw new IllegalArgumentException("Illegal characters in SVG path.");
+    // If there are more than 1 letters or delimiters next to one another
+    } else if (path.matches("[a-zA-Z.\\-]{2,}")) {
+      throw new IllegalArgumentException("Multiple letters or delimiters found next to one another in SVG path.");
+    // First character in path must be a command
+    } else if (path.matches("^[a-zA-Z]")) {
+      throw new IllegalArgumentException("Start of SVG path is not a letter.");
+    }
+
+    // Split on SVG path characters to get a list of instructions, keeping the SVG commands
+    return path.split("(?=[mlhvcsqtazMLHVCSQTAZ])");
+  }
+
+  private List<String> getSvgPathAttributes(Document svg) {
+    List<String> paths = new ArrayList<>();
+
+    for (Node elem : asList(svg.getElementsByTagName("path"))) {
+      paths.add(elem.getAttributes().getNamedItem("d").getNodeValue());
+    }
+
+    return paths;
+  }
+
+  @Override
+  protected void parseFile(String filePath)
+      throws ParserConfigurationException, IOException, SAXException, IllegalArgumentException {
+    Document svg = getSvgDocument(filePath);
+
+    for (String path : getSvgPathAttributes(svg)) {
+      preProcessPath(path);
+    }
   }
 
   @Override

src/parser/XmlUtil.java

@@ -14,6 +14,7 @@ public final class XmlUtil {
     return n.getLength()==0?
         Collections.emptyList(): new NodeListWrapper(n);
   }
+
   static final class NodeListWrapper extends AbstractList<Node>
       implements RandomAccess {
     private final NodeList list;

test/LineTest.java

@@ -3,7 +3,7 @@ import shapes.Line;
 
 import static org.junit.Assert.*;
 
-public class TestSuite {
+public class LineTest {
   // TODO: Create tests for shapes.Shapes class.
 
   @Test