Add Container.Indexed.getItemIds(int, int) for a range of items (#8028)

This permits optimization of data fetches from various containers
where getting single items by index in a loop might be costly.

Also add a helper method in ContainerHelpers to make it easier to
implement the new method where performance of fetching an id by index is
not an issue. SQLContainer still uses this helper instead of an
optimized implementation.

1 files changed, 121 insertions, 1 deletions

diff --git a/server/tests/src/com/vaadin/data/util/TestIndexedContainer.java b/server/tests/src/com/vaadin/data/util/TestIndexedContainer.java
index 156ff83883..da2e2feac7 100644
--- a/server/tests/src/com/vaadin/data/util/TestIndexedContainer.java
+++ b/server/tests/src/com/vaadin/data/util/TestIndexedContainer.java
@@ -1,7 +1,9 @@
 package com.vaadin.data.util;
 
+import java.util.List;
+
 import com.vaadin.data.Item;
-import com.vaadin.data.util.IndexedContainer;
+import com.vaadin.data.RangeOutOfContainerBoundsException;
 
 public class TestIndexedContainer extends AbstractInMemoryContainerTest {
 
@@ -268,4 +270,122 @@ public class TestIndexedContainer extends AbstractInMemoryContainerTest {
         counter.assertNone();
     }
 
+    // Ticket 8028
+    public void testGetItemIdsRangeIndexOutOfBounds() {
+        IndexedContainer ic = new IndexedContainer();
+        try {
+            ic.getItemIds(-1, 10);
+            fail("Container returned items starting from index -1, something very wrong here!");
+        } catch (IndexOutOfBoundsException e) {
+            // This is expected...
+        } catch (Exception e) {
+            // Should not happen!
+            fail("Container threw unspecified exception when fetching a range of items and the range started from -1");
+        }
+
+    }
+
+    // Ticket 8028
+    public void testGetItemIdsRangeIndexOutOfBounds2() {
+        IndexedContainer ic = new IndexedContainer();
+        ic.addItem(new Object());
+        try {
+            ic.getItemIds(2, 1);
+            fail("Container returned items starting from index -1, something very wrong here!");
+        } catch (IndexOutOfBoundsException e) {
+            // This is expected...
+        } catch (Exception e) {
+            // Should not happen!
+            fail("Container threw unspecified exception when fetching a out of bounds range of items");
+        }
+
+    }
+
+    // Ticket 8028
+    public void testGetItemIdsRangeZeroRange() {
+        IndexedContainer ic = new IndexedContainer();
+        ic.addItem(new Object());
+        try {
+            List<Object> itemIds = ic.getItemIds(1, 0);
+
+            assertTrue(
+                    "Container returned actual values when asking for 0 items...",
+                    itemIds.isEmpty());
+        } catch (Exception e) {
+            // Should not happen!
+            fail("Container threw unspecified exception when fetching 0 items...");
+        }
+
+    }
+
+    // Ticket 8028
+    public void testGetItemIdsRangeNegativeRange() {
+        IndexedContainer ic = new IndexedContainer();
+        ic.addItem(new Object());
+        try {
+            List<Object> itemIds = ic.getItemIds(1, -1);
+
+            assertTrue(
+                    "Container returned actual values when asking for -1 items...",
+                    itemIds.isEmpty());
+        } catch (IllegalArgumentException e) {
+            // this is expected
+
+        } catch (Exception e) {
+            // Should not happen!
+            fail("Container threw unspecified exception when fetching -1 items...");
+        }
+
+    }
+
+    // Ticket 8028
+    public void testGetItemIdsRangeIndexOutOfBoundsDueToSizeChange() {
+        IndexedContainer ic = new IndexedContainer();
+        ic.addItem(new Object());
+        try {
+            ic.getItemIds(0, 10);
+            fail("Container returned items when the range was >> container size");
+        } catch (RangeOutOfContainerBoundsException e) {
+            // This is expected...
+            assertTrue(e.isAdditionalParametersSet());
+            assertEquals(0, e.getStartIndex());
+            assertEquals(10, e.getNumberOfIds());
+            assertEquals(1, e.getContainerCurrentSize());
+
+        } catch (IndexOutOfBoundsException e) {
+            fail("Container threw wrong exception when the range exceeded container size... ");
+        } catch (Exception e) {
+            // Should not happen!
+            fail("Container threw unspecified exception when fetching a range of items and the range started from -1");
+        }
+    }
+
+    // Ticket 8028
+    public void testGetItemIdsRangeBaseCase() {
+        IndexedContainer ic = new IndexedContainer();
+        String object1 = new String("Obj1");
+        String object2 = new String("Obj2");
+        String object3 = new String("Obj3");
+        String object4 = new String("Obj4");
+        String object5 = new String("Obj5");
+
+        ic.addItem(object1);
+        ic.addItem(object2);
+        ic.addItem(object3);
+        ic.addItem(object4);
+        ic.addItem(object5);
+
+        try {
+            List<Object> itemIds = ic.getItemIds(1, 2);
+
+            assertTrue(itemIds.contains(object2));
+            assertTrue(itemIds.contains(object3));
+            assertEquals(2, itemIds.size());
+
+        } catch (Exception e) {
+            // Should not happen!
+            fail("Container threw  exception when fetching a range of items ");
+        }
+    }
+
 }