add CLI interface and impl for category

0-Plugin/src/main/java/cli/Subcommand.java

@@ -0,0 +1,11 @@
+package cli;
+
+public interface Subcommand {
+
+	public String getSubcommand();
+
+	public String executeSubcommand(String[] args);
+
+
+
+}

0-Plugin/src/main/java/cli/category/CategoryCommands.java

@@ -0,0 +1,39 @@
+package cli.category;
+
+import cli.Subcommand;
+
+import java.util.HashMap;
+import java.util.function.Function;
+
+public class CategoryCommands implements Subcommand {
+
+	final private CategoryCliAdapter categoryCliAdapter;
+	final private HashMap<String, Function<String[], String>> commands = new HashMap<>();
+
+	public CategoryCommands(CategoryCliAdapter categoryCliAdapter) {
+		this.categoryCliAdapter = categoryCliAdapter;
+		commands.put("add", this::addCategory);
+		commands.put("get", this::getCategories);
+	}
+
+	@Override
+	public String getSubcommand() {
+		return "category";
+	}
+
+	@Override
+	public String executeSubcommand(String[] args) {
+		return commands.get(args[0]).apply(args);
+	}
+
+	private String addCategory(String[] args) {
+		categoryCliAdapter.addCategory(args[1]);
+		return "Added the new category";
+	}
+
+	private String getCategories(String[] _ignored) {
+		return "Available Categories:" + System.lineSeparator() + String.join(System.lineSeparator(),
+		                                                                      categoryCliAdapter.getCategories());
+	}
+
+}

0-Plugin/src/test/java/cli/category/CategoryCommandsTest.java

@@ -0,0 +1,41 @@
+package cli.category;
+
+import org.junit.jupiter.api.Test;
+import org.mockito.ArgumentCaptor;
+
+import java.util.Set;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.mockito.Mockito.doNothing;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+
+class CategoryCommandsTest {
+
+	CategoryCliAdapter mockAdapter = mock(CategoryCliAdapter.class);
+
+	@Test
+	void addCommandWorks() {
+		var categoryName = "funStuff";
+		ArgumentCaptor<String> valueCapture = ArgumentCaptor.forClass(String.class);
+		doNothing().when(mockAdapter).addCategory(valueCapture.capture());
+		var sut = new CategoryCommands(mockAdapter);
+
+		var returnValue = sut.executeSubcommand(new String[]{"add", categoryName});
+
+		assertEquals(categoryName, valueCapture.getValue());
+		assertEquals("Added the new category", returnValue);
+	}
+
+	@Test
+	void getCommandWorks() {
+		var sut = new CategoryCommands(mockAdapter);
+		when(mockAdapter.getCategories()).thenReturn(Set.of("funStuff", "workStuff"));
+		var returnValue = sut.executeSubcommand(new String[]{"get"});
+
+		var expected =
+				"Available Categories:" + System.lineSeparator() + "funStuff" + System.lineSeparator() + "workStuff";
+
+		assertEquals(expected, returnValue);
+	}
+}