Cleaned up structure.

src/main/java/nl/andrewlalis/human_task_distributor/HumanTaskDistributor.java

@@ -1,13 +1,10 @@
 package nl.andrewlalis.human_task_distributor;
 
+import nl.andrewlalis.human_task_distributor.commands.DistributeTasks;
 import nl.andrewlalis.human_task_distributor.commands.PrepareTasksList;
 import org.apache.commons.cli.*;
 import org.apache.commons.csv.CSVFormat;
 
-import java.util.List;
-import java.util.Map;
-import java.util.Set;
-
 public class HumanTaskDistributor {
 	public static final CSVFormat CSV_FORMAT = CSVFormat.RFC4180;
 
@@ -15,44 +12,15 @@ public class HumanTaskDistributor {
 		final Options options = getOptions();
 		CommandLineParser cmdParser = new DefaultParser();
 		try {
-
-			FileParser fileParser = new FileParser();
-			FileWriter fileWriter = new FileWriter();
 			CommandLine cmd = cmdParser.parse(options, args);
 			if (cmd.hasOption("ptl")) {
-				String[] values = cmd.getOptionValues("ptl");
+				new PrepareTasksList().execute(cmd);
-				new PrepareTasksList().execute(values);
+			} else if (cmd.hasOption("hl") && cmd.hasOption("tl")) {
-				return;
+				new DistributeTasks().execute(cmd);
 			}
-
+			throw new IllegalArgumentException("Invalid command.");
-			if (!cmd.hasOption("hl") || !cmd.hasOption("tl")) {
-				throw new IllegalArgumentException("When not preparing a tasks-list, hl and tl are required.");
-			}
-
-			Map<Human, Float> nameWeightMap = fileParser.parseHumanList(cmd.getOptionValue("hl"));
-			Set<Task> tasks = fileParser.parseTaskList(cmd.getOptionValue("tl"));
-			String[] previousDistributionPaths = cmd.getOptionValues("prev");
-			if (previousDistributionPaths == null) previousDistributionPaths = new String[0];
-			List<Map<Human, Set<Task>>> previousDistributions = fileParser.parsePreviousTaskDistributions(previousDistributionPaths);
-
-			long start = System.currentTimeMillis();
-			Map<Human, Set<Task>> taskDistributions = new Distributor().generateDistribution(nameWeightMap, tasks, previousDistributions);
-			long durationMillis = System.currentTimeMillis() - start;
-			System.out.printf(
-					"Completed distribution of %d tasks to %d people in %d ms.%n",
-					tasks.size(),
-					taskDistributions.keySet().size(),
-					durationMillis
-			);
-
-			// Write to a file.
-			final String filePath = cmd.hasOption("o") ? cmd.getOptionValue("o") : "distribution.csv";
-			fileWriter.write(taskDistributions, filePath);
-			System.out.println("Wrote task distribution data to " + filePath);
-
 		} catch (Exception e) {
 			System.err.println("Error: " + e.getMessage());
-			e.printStackTrace();
 			HelpFormatter hf = new HelpFormatter();
 			hf.printHelp("HumanTaskDistributor", options);
 			System.exit(1);

src/main/java/nl/andrewlalis/human_task_distributor/commands/Command.java

@@ -1,6 +1,8 @@
 package nl.andrewlalis.human_task_distributor.commands;
 
+import org.apache.commons.cli.CommandLine;
+
 public interface Command {
 
-	void execute(String[] args);
+	void execute(CommandLine cmd);
 }

src/main/java/nl/andrewlalis/human_task_distributor/commands/DistributeTasks.java

@@ -0,0 +1,41 @@
+package nl.andrewlalis.human_task_distributor.commands;
+
+import nl.andrewlalis.human_task_distributor.*;
+import org.apache.commons.cli.CommandLine;
+
+import java.io.IOException;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+public class DistributeTasks implements Command {
+	@Override
+	public void execute(CommandLine cmd) {
+		final FileParser fileParser = new FileParser();
+		final FileWriter fileWriter = new FileWriter();
+		Map<Human, Float> nameWeightMap = fileParser.parseHumanList(cmd.getOptionValue("hl"));
+		Set<Task> tasks = fileParser.parseTaskList(cmd.getOptionValue("tl"));
+		String[] previousDistributionPaths = cmd.getOptionValues("prev");
+		if (previousDistributionPaths == null) previousDistributionPaths = new String[0];
+		List<Map<Human, Set<Task>>> previousDistributions = fileParser.parsePreviousTaskDistributions(previousDistributionPaths);
+
+		long start = System.currentTimeMillis();
+		Map<Human, Set<Task>> taskDistributions = new Distributor().generateDistribution(nameWeightMap, tasks, previousDistributions);
+		long durationMillis = System.currentTimeMillis() - start;
+		System.out.printf(
+				"Created distribution of %d tasks to %d people in %d ms.%n",
+				tasks.size(),
+				taskDistributions.keySet().size(),
+				durationMillis
+		);
+
+		// Write to a file.
+		final String filePath = cmd.hasOption("o") ? cmd.getOptionValue("o") : "distribution.csv";
+		try {
+			fileWriter.write(taskDistributions, filePath);
+			System.out.println("Wrote task distribution data to " + filePath);
+		} catch (IOException e) {
+			System.err.println("Couldn't write to file: " + e.getMessage());
+		}
+	}
+}

src/main/java/nl/andrewlalis/human_task_distributor/commands/PrepareTasksList.java

@@ -3,18 +3,20 @@ package nl.andrewlalis.human_task_distributor.commands;
 import nl.andrewlalis.human_task_distributor.FileParser;
 import nl.andrewlalis.human_task_distributor.FileWriter;
 import nl.andrewlalis.human_task_distributor.Task;
+import org.apache.commons.cli.CommandLine;
 
 import java.io.IOException;
 import java.util.Set;
 
 public class PrepareTasksList implements Command {
 	@Override
-	public void execute(String[] args) {
+	public void execute(CommandLine cmd) {
-		if (args.length != 2) {
+		String[] values = cmd.getOptionValues("ptl");
+		if (values.length != 2) {
 			throw new IllegalArgumentException("Expected exactly 2 parameters for ptl arg.");
 		}
-		String filePath = args[0].trim();
+		String filePath = values[0].trim();
-		String regex = args[1].trim();
+		String regex = values[1].trim();
 		Set<Task> tasks = new FileParser().parseTaskList(filePath, regex);
 		System.out.println("Read " + tasks.size() + " tasks from file.");
 		String outFilePath = filePath.replaceFirst("\\..*", ".csv");