An interface (and an implementing abstract class) that represents the result of the connection

Author: guy120494

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

@@ -0,0 +1,45 @@
+/**
+ * Copyright 2016 Yurii Rashkovskii
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ */
+package graphql.annotations.connection;
+
+import java.util.Iterator;
+
+public abstract class AbstarctPaginatedData<T> implements PaginatedData<T> {
+
+    private boolean hasPreviousPage;
+    private boolean hasNextPage;
+    private Iterable<T> data;
+
+    public AbstarctPaginatedData(boolean hasPreviousPage, boolean hasNextPage, Iterable<T> data) {
+        this.hasNextPage = hasNextPage;
+        this.hasPreviousPage = hasPreviousPage;
+        this.data = data;
+    }
+
+    @Override
+    public boolean hasNextPage() {
+        return hasNextPage;
+    }
+
+    @Override
+    public boolean hasPreviousPage() {
+        return hasPreviousPage;
+    }
+
+    @Override
+    public Iterator<T> iterator() {
+        return data.iterator();
+    }
+}

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

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+/**
+ * Copyright 2016 Yurii Rashkovskii
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ */
+package graphql.annotations.connection;
+
+/**
+ * This class is the result of a connection. Every Graphql connection field must return this interface
+ * <p>
+ * NOTE: this interface extends Iterable. The data is retrieved from the "iterator" function.
+ * Please implement the iterator with data structure that has order
+ *
+ * @param <T> the data of which we paginated over
+ */
+public interface PaginatedData<T> extends Iterable<T> {
+
+    /**
+     * Whether or not this is the last page
+     *
+     * @return true if there is a next page, false otherwise
+     */
+    boolean hasNextPage();
+
+    /**
+     * Whether or not this is the first page
+     *
+     * @return true if there is a previous page, false otherwise
+     */
+    boolean hasPreviousPage();
+
+    /**
+     * get the encoded cursor of the entity
+     *
+     * @param entity the entity
+     * @return String representation of the cursor of the entity
+     */
+    String getCursor(T entity);
+}