Added this simple (and naive) class that implements the AbstractPaginatedData

Author: guy120494

src/main/java/graphql/annotations/connection/SimplePaginatedData.java

@@ -0,0 +1,46 @@
+package graphql.annotations.connection;
+
+import java.nio.charset.StandardCharsets;
+import java.util.Iterator;
+
+import static java.util.Base64.getEncoder;
+
+public class SimplePaginatedData<T> extends AbstractPaginatedData<T> {
+    private static final String DUMMY_CURSOR_PREFIX = "simple-cursor";
+    private final String prefix;
+
+    public SimplePaginatedData(boolean hasPreviousPage, boolean hasNextPage, Iterable<T> data) {
+        this(hasPreviousPage, hasNextPage, data, DUMMY_CURSOR_PREFIX);
+    }
+
+    public SimplePaginatedData(boolean hasPreviousPage, boolean hasNextPage, Iterable<T> data, String prefix) {
+        super(hasPreviousPage, hasNextPage, data);
+        this.prefix = prefix;
+    }
+
+    /**
+     * creates the cursor by offset (i.e first entity has cursor 0, the second has 1 and so on)
+     * NOTE: to make it consistent, please make the data ordered
+     *
+     * @param entity the entity
+     * @return the cursor of the entity (i.e the offset)
+     */
+    @Override
+    public String getCursor(T entity) {
+        Iterator<T> iterator = data.iterator();
+        long offset = 0;
+        for (; iterator.hasNext(); ) {
+            T next = iterator.next();
+            if (entity.equals(next)) {
+                break;
+            }
+            offset++;
+        }
+        return createCursor(offset);
+    }
+
+    private String createCursor(long offset) {
+        byte[] bytes = (prefix + Long.toString(offset)).getBytes(StandardCharsets.UTF_8);
+        return getEncoder().encodeToString(bytes);
+    }
+}