558321 design general purpose interfaces to empower reporting

tests/org.eclipse.passage.loc.yars.api.tests/src/org/eclipse/passage/loc/yars/internal/api/pagination/Fetch.java

@@ -0,0 +1,45 @@
+/*******************************************************************************
+ * Copyright (c) 2019 ArSysOp
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-2.0.
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *
+ * Contributors:
+ *     ArSysOp - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.passage.loc.yars.internal.api.pagination;
+
+import java.util.List;
+import java.util.stream.Collectors;
+import java.util.stream.IntStream;
+
+import org.eclipse.passage.loc.yars.internal.api.FetchedData;
+import org.eclipse.passage.loc.yars.internal.api.model.InMemoryStorage;
+import org.eclipse.passage.loc.yars.internal.api.model.StoredEntry;
+
+@SuppressWarnings("restriction")
+
+class Fetch implements FetchedData<InMemoryStorage, StoredEntry> {
+
+	private final PaginationSettings settings;
+	private final InMemoryStorage storage;
+
+	Fetch(PaginationSettings settings, InMemoryStorage storage) {
+		this.settings = settings;
+		this.storage = storage;
+	}
+
+	@Override
+	public List<StoredEntry> get() {
+		List<StoredEntry> all = storage.entries();
+		return IntStream.range(settings.from(), settings.to()) //
+				.filter(i -> i >= 0) //
+				.filter(i -> i < all.size()) //
+				.mapToObj(all::get) //
+				.collect(Collectors.toList());
+	}
+
+}

tests/org.eclipse.passage.loc.yars.api.tests/src/org/eclipse/passage/loc/yars/internal/api/pagination/Page.java

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+/*******************************************************************************
+ * Copyright (c) 2019 ArSysOp
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-2.0.
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *
+ * Contributors:
+ *     ArSysOp - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.passage.loc.yars.internal.api.pagination;
+
+import org.eclipse.passage.loc.yars.internal.api.FetchedData;
+import org.eclipse.passage.loc.yars.internal.api.Query;
+import org.eclipse.passage.loc.yars.internal.api.model.InMemoryStorage;
+import org.eclipse.passage.loc.yars.internal.api.model.StoredEntry;
+
+@SuppressWarnings("restriction")
+public class Page implements Query<InMemoryStorage, StoredEntry, PaginationSettings> {
+
+	@Override
+	public String id() {
+		return "PAGE"; //$NON-NLS-1$
+	}
+
+	@Override
+	public String description() {
+		return "Fetch paginated original entries from in-memory storage"; //$NON-NLS-1$
+	}
+
+	@Override
+	public FetchedData<InMemoryStorage, StoredEntry> data(InMemoryStorage storage, PaginationSettings params) {
+		return new Fetch(params, storage);
+	}
+
+}

tests/org.eclipse.passage.loc.yars.api.tests/src/org/eclipse/passage/loc/yars/internal/api/pagination/PaginationSettings.java

@@ -0,0 +1,36 @@
+/*******************************************************************************
+ * Copyright (c) 2019 ArSysOp
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-2.0.
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *
+ * Contributors:
+ *     ArSysOp - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.passage.loc.yars.internal.api.pagination;
+
+import org.eclipse.passage.loc.yars.internal.api.FetchParams;
+
+@SuppressWarnings("restriction")
+class PaginationSettings implements FetchParams {
+
+	private final int no;
+	private final int length;
+
+	PaginationSettings(int no, int length) {
+		this.no = no;
+		this.length = length;
+	}
+
+	int from() {
+		return no * length;
+	}
+
+	int to() {
+		return (no + 1) * length;
+	}
+
+}

tests/org.eclipse.passage.loc.yars.api.tests/src/org/eclipse/passage/loc/yars/internal/api/pagination/PaginationTest.java

@@ -0,0 +1,64 @@
+/*******************************************************************************
+ * Copyright (c) 2019 ArSysOp
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-2.0.
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *
+ * Contributors:
+ *     ArSysOp - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.passage.loc.yars.internal.api.pagination;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
+import java.util.List;
+
+import org.eclipse.passage.loc.yars.internal.api.model.InMemoryStorage;
+import org.eclipse.passage.loc.yars.internal.api.model.StoredEntry;
+import org.junit.Test;
+
+public class PaginationTest {
+
+	@Test
+	public void testFirstPage() {
+		List<StoredEntry> result = pageContent(0);
+		assertEquals(3, result.size());
+		assertTrue(result.stream().allMatch(e -> e.origin().equals("page 1"))); //$NON-NLS-1$
+	}
+
+	@Test
+	public void testMidPage() {
+		List<StoredEntry> result = pageContent(1);
+		assertEquals(3, result.size());
+		assertTrue(result.stream().allMatch(e -> e.origin().equals("page 2"))); //$NON-NLS-1$
+	}
+
+	@Test
+	public void testNotFullPage() {
+		List<StoredEntry> result = pageContent(2);
+		assertEquals(1, result.size());
+		assertEquals("page 3", result.get(0).origin()); //$NON-NLS-1$
+	}
+
+	@SuppressWarnings("restriction")
+	private List<StoredEntry> pageContent(int no) {
+		return new Page().data(base(), new PaginationSettings(no, 3)).get();
+	}
+
+	private InMemoryStorage base() {
+		return new InMemoryStorage( //
+				new StoredEntry("1.0", "page 1"), //$NON-NLS-1$ //$NON-NLS-2$
+				new StoredEntry("1.1", "page 1"), //$NON-NLS-1$ //$NON-NLS-2$
+				new StoredEntry("1.2", "page 1"), //$NON-NLS-1$ //$NON-NLS-2$
+				new StoredEntry("2.0", "page 2"), //$NON-NLS-1$ //$NON-NLS-2$
+				new StoredEntry("2.1", "page 2"), //$NON-NLS-1$ //$NON-NLS-2$
+				new StoredEntry("2.2", "page 2"), //$NON-NLS-1$ //$NON-NLS-2$
+				new StoredEntry("3.1", "page 3")//$NON-NLS-1$ //$NON-NLS-2$
+		);
+	}
+
+}