Added mmultiple commands including music, added Music Module as well as Pagination(s, needs cleaning) and more

src/test/java/Main.java

@@ -0,0 +1,53 @@
+import java.util.*;
+
+public class Main {
+
+    private static List<String> list = new ArrayList<>();
+    public static void main(String[] args) {
+        if (list.isEmpty()) {
+            for (int i = 0; i < 25; i++) {
+                list.add("Item No. " + (i + 1));
+            }
+        }
+        List<String> page = getPage(list, 3, 5);
+        System.out.println("Page: " + (3));
+        page.forEach(System.out::println);
+        List<List<String>> pages = getPages(list, 5);
+
+        page = pages.get(2);
+        System.out.println("Page: " + (3));
+        page.forEach(System.out::println);
+        /*for(int i = 0; i < pages.size(); i++) {
+            List<String> page = pages.get(i);
+            System.out.println("Page: " + (i + 1));
+            page.forEach(System.out::println);
+        }*/
+    }
+
+    public static List<String> getPage(List<String> sourceList, int page, int pageSize) {
+        if(pageSize <= 0 || page <= 0) {
+            throw new IllegalArgumentException("invalid page size: " + pageSize);
+        }
+
+        int fromIndex = (page - 1) * pageSize;
+        if(sourceList == null || sourceList.size() < fromIndex){
+            return Collections.emptyList();
+        }
+
+        // toIndex exclusive
+        return sourceList.subList(fromIndex, Math.min(fromIndex + pageSize, sourceList.size()));
+    }
+
+    public static List<List<String>> getPages(Collection<String> c, Integer pageSize) {
+        if (c == null)
+            return Collections.emptyList();
+        List<String> list = new ArrayList<>(c);
+        if (pageSize == null || pageSize <= 0 || pageSize > list.size())
+            pageSize = list.size();
+        int numPages = (int) Math.ceil((double)list.size() / (double)pageSize);
+        List<List<String>> pages = new ArrayList<>(numPages);
+        for (int pageNum = 0; pageNum < numPages;)
+            pages.add(list.subList(pageNum * pageSize, Math.min(++pageNum * pageSize, list.size())));
+        return pages;
+    }
+}