If no HU matches, then do *not* show every HU

Also:
* CreateViewRequest: javadoc
* WEBUI_Picking_OpenHUsToPick: minor formatting

557: Picking Window: Open HU Selection window filtering 

Task-Url: #557

src/main/java/de/metas/ui/web/handlingunits/HUEditorViewFactory.java

@@ -6,6 +6,8 @@
 import java.util.Objects;
 import java.util.Set;
 
+import javax.annotation.Nullable;
+
 import org.adempiere.ad.dao.IQueryFilter;
 import org.adempiere.ad.dao.ISqlQueryFilter;
 import org.adempiere.model.PlainContextAware;
@@ -44,6 +46,7 @@
 import de.metas.ui.web.window.descriptor.factory.DocumentDescriptorFactory;
 import de.metas.ui.web.window.descriptor.factory.standard.LayoutFactory;
 import de.metas.ui.web.window.descriptor.sql.SqlDocumentEntityDataBindingDescriptor;
+import lombok.NonNull;
 
 /*
  * #%L
@@ -106,8 +109,7 @@ private SqlViewBinding createSqlViewBinding()
 				.setDisplayFieldNames(displayFieldNames)
 				.setSqlWhereClause(I_M_HU.COLUMNNAME_M_HU_Item_Parent_ID + " is null" // top level
 						+ " AND " + I_M_HU.COLUMNNAME_IsActive + "=" + DB.TO_BOOLEAN(Boolean.TRUE)) // active
-				.setRowIdsConverter(HUSqlViewRowIdsConverter.instance)
-		;
+				.setRowIdsConverter(HUSqlViewRowIdsConverter.instance);
 
 		//
 		// View Fields
@@ -133,7 +135,7 @@ private SqlViewBinding createSqlViewBinding()
 					.addViewFilterConverter(HUBarcodeSqlDocumentFilterConverter.FILTER_ID, HUBarcodeSqlDocumentFilterConverter.instance)
 					.addViewFilterConverter(HUIdsFilterHelper.FILTER_ID, HUIdsFilterHelper.SQL_DOCUMENT_FILTER_CONVERTER);
 		}
-		
+
 		//
 		return sqlViewBinding.build();
 	}
@@ -223,7 +225,9 @@ public HUEditorView createView(final CreateViewRequest request)
 			referencingTableName = null;
 		}
 
+		@SuppressWarnings("deprecation") // as long as the deprecated getFilterOnlyIds() is around we can't ignore it
 		final List<DocumentFilter> stickyFilters = extractStickyFilters(request.getStickyFilters(), request.getFilterOnlyIds());
+
 		final List<DocumentFilter> filters = request.getOrUnwrapFilters(getSqlViewBinding().getViewFilterDescriptors());
 
 		final HUEditorView.Builder huViewBuilder = HUEditorView.builder(getSqlViewBinding())
@@ -248,13 +252,22 @@ public HUEditorView createView(final CreateViewRequest request)
 		return huViewBuilder.build();
 	}
 
-	private static List<DocumentFilter> extractStickyFilters(final List<DocumentFilter> requestStickyFilters, final Set<Integer> huIds)
+	/**
+	 * 
+	 * @param requestStickyFilters
+	 * @param huIds {@code null} means "no restriction". Empty means "select none"
+	 * @return
+	 */
+	private static List<DocumentFilter> extractStickyFilters(
+			@NonNull final List<DocumentFilter> requestStickyFilters,
+			@Nullable final Set<Integer> huIds)
 	{
-		List<DocumentFilter> stickyFilters = new ArrayList<>(requestStickyFilters);
+		final List<DocumentFilter> stickyFilters = new ArrayList<>(requestStickyFilters);
 
 		final DocumentFilter stickyFilter_HUIds_Existing = HUIdsFilterHelper.findExistingOrNull(stickyFilters);
+
 		// Create the sticky filter by HUIds from builder's huIds (if any huIds)
-		if (stickyFilter_HUIds_Existing == null && !huIds.isEmpty())
+		if (stickyFilter_HUIds_Existing == null && huIds != null)
 		{
 			final DocumentFilter stickyFilter_HUIds_New = HUIdsFilterHelper.createFilter(huIds);
 			stickyFilters.add(0, stickyFilter_HUIds_New);

src/main/java/de/metas/ui/web/handlingunits/HUIdsFilterHelper.java

@@ -11,6 +11,7 @@
 import org.adempiere.model.PlainContextAware;
 import org.adempiere.util.Services;
 
+import com.google.common.annotations.VisibleForTesting;
 import com.google.common.base.Preconditions;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
@@ -57,13 +58,18 @@ public final class HUIdsFilterHelper
 	@ToString
 	public static final class HUIdsFilterData
 	{
-		public static HUIdsFilterData ofHUIds(final Collection<Integer> huIds)
+		/**
+		 * 
+		 * @param huIds may be empty, but not null. Empty means that <b>no</b> HU will be matched.
+		 * @return
+		 */
+		public static HUIdsFilterData ofHUIds(@NonNull final Collection<Integer> huIds)
 		{
 			final IHUQueryBuilder initialFilter = null;
 			return new HUIdsFilterData(huIds, initialFilter);
 		}
 
-		public static HUIdsFilterData ofHUQuery(final IHUQueryBuilder initialHUQuery)
+		public static HUIdsFilterData ofHUQuery(@NonNull final IHUQueryBuilder initialHUQuery)
 		{
 			final Collection<Integer> huIds = null;
 			return new HUIdsFilterData(huIds, initialHUQuery);
@@ -76,17 +82,21 @@ public static HUIdsFilterData newEmpty()
 			return new HUIdsFilterData(huIds, initialHUQuery);
 		}
 
+		/**
+		 * Important: {@code null} means "no restriction" (i.e. we can select allHUs) whereas empty means that no HU matches the filter.
+		 */
 		private final ImmutableSet<Integer> initialHUIds;
+
 		private final IHUQueryBuilder initialHUQuery;
 
 		private final Set<Integer> mustHUIds;
 		private final Set<Integer> shallNotHUIds;
 
 		private HUIdsFilterData(
-				@Nullable final Collection<Integer> initialHUIds, 
+				@Nullable final Collection<Integer> initialHUIds,
 				@Nullable final IHUQueryBuilder initialHUQuery)
 		{
-			this.initialHUIds = initialHUIds != null ? ImmutableSet.copyOf(initialHUIds) : ImmutableSet.of();
+			this.initialHUIds = initialHUIds == null ? null : ImmutableSet.copyOf(initialHUIds);
 			this.initialHUQuery = initialHUQuery;
 			mustHUIds = new HashSet<>();
 			shallNotHUIds = new HashSet<>();
@@ -165,9 +175,8 @@ public static final class MutableHUIdsList
 
 	public static final String FILTER_ID = "huIds";
 	private static final String FILTER_PARAM_Data = "$data";
-
-	public static final transient HUIdsSqlDocumentFilterConverter SQL_DOCUMENT_FILTER_CONVERTER = new HUIdsSqlDocumentFilterConverter();
 
+	public static final transient HUIdsSqlDocumentFilterConverter SQL_DOCUMENT_FILTER_CONVERTER = new HUIdsSqlDocumentFilterConverter();
 
 	public static final DocumentFilter findExistingOrNull(final Collection<DocumentFilter> filters)
 	{
@@ -181,7 +190,12 @@ public static final DocumentFilter findExistingOrNull(final Collection<DocumentF
 				.findFirst().orElse(null);
 	}
 
-	public static final DocumentFilter createFilter(final Collection<Integer> huIds)
+	/**
+	 * @param huIds huIds may be empty, but not null. Empty means that <b>no</b> HU will be matched.
+	 * 
+	 * @return
+	 */
+	public static final DocumentFilter createFilter(@NonNull final Collection<Integer> huIds)
 	{
 		final HUIdsFilterData filterData = HUIdsFilterData.ofHUIds(huIds);
 		return DocumentFilter.singleParameterFilter(FILTER_ID, FILTER_PARAM_Data, Operator.EQUAL, filterData);
@@ -233,6 +247,9 @@ public static boolean isHighVolume(final List<DocumentFilter> stickyFilters)
 
 	public static final class HUIdsSqlDocumentFilterConverter implements SqlDocumentFilterConverter
 	{
+		@VisibleForTesting
+		static final String SQL_TRUE = "1=1";
+
 		private HUIdsSqlDocumentFilterConverter()
 		{
 		}
@@ -243,9 +260,9 @@ public String getSql(final SqlParamsCollector sqlParamsOut, final DocumentFilter
 			final HUIdsFilterData huIdsFilter = extractFilterData(filter);
 			final ImmutableList<Integer> onlyHUIds = ImmutableList.copyOf(Iterables.concat(huIdsFilter.getInitialHUIds(), huIdsFilter.getMustHUIds()));
 
-			if (onlyHUIds.isEmpty() && !huIdsFilter.hasInitialHUQuery())
+			if (onlyHUIds == null && !huIdsFilter.hasInitialHUQuery())
 			{
-				return "1=1"; // pass through
+				return SQL_TRUE; // no restrictions were specified; pass through
 			}
 
 			//
@@ -258,7 +275,7 @@ public String getSql(final SqlParamsCollector sqlParamsOut, final DocumentFilter
 			huQuery.setContext(PlainContextAware.newOutOfTrx());
 
 			// Only HUs
-			if (!onlyHUIds.isEmpty())
+			if (onlyHUIds != null)
 			{
 				huQuery.addOnlyHUIds(onlyHUIds);
 			}

src/main/java/de/metas/ui/web/picking/process/WEBUI_Picking_OpenHUsToPick.java

@@ -92,7 +92,7 @@ protected String doIt()
 				.build();
 
 		final List<I_M_HU> availableHUsToPick = huPickingSlotBL.retrieveAvailableHUsToPick(request);
-		final List<Integer> availableHUsToPickIDs = availableHUsToPick.stream().map(hu->hu.getM_HU_ID()).collect(Collectors.toList());
+		final List<Integer> availableHUsToPickIDs = availableHUsToPick.stream().map(hu -> hu.getM_HU_ID()).collect(Collectors.toList());
 
 		final RelatedProcessDescriptor processToPickSelectedHU = RelatedProcessDescriptor.builder()
 				.processId(adProcessDAO.retriveProcessIdByClassIfUnique(Env.getCtx(), WEBUI_Picking_PickSelectedHU.class))

src/main/java/de/metas/ui/web/view/CreateViewRequest.java

@@ -130,7 +130,7 @@ public static final Builder deleteStickyFilterBuilder(
 	private final DocumentFiltersList filters;
 
 	/**
-	 * This one is becoming king of legacy.... it's a particular filter which filters by given IDs.
+	 * This one is becoming king of legacy.... it's a particular kind of sticky filter which filters by given IDs.
 	 * 
 	 * @deprecated please rather use {@link #getFilters()} {@link #getStickyFilters()}.
 	 */

src/test/java/de/metas/ui/web/handlingunits/HUIdsFilterHelperTest.java

@@ -0,0 +1,50 @@
+package de.metas.ui.web.handlingunits;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import org.junit.Test;
+
+import com.google.common.collect.ImmutableList;
+
+import de.metas.ui.web.document.filter.DocumentFilter;
+import de.metas.ui.web.document.filter.sql.SqlParamsCollector;
+import de.metas.ui.web.handlingunits.HUIdsFilterHelper.HUIdsSqlDocumentFilterConverter;
+
+/*
+ * #%L
+ * metasfresh-webui-api
+ * %%
+ * Copyright (C) 2017 metas GmbH
+ * %%
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation, either version 2 of the
+ * License, or (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public
+ * License along with this program. If not, see
+ * <http://www.gnu.org/licenses/gpl-2.0.html>.
+ * #L%
+ */
+
+public class HUIdsFilterHelperTest
+{
+	/**
+	 * Verifies that if {@link HUIdsFilterHelper#createFilter(java.util.Collection)} is called with an empty list, 
+	 * then the filter's SQL does <b>not</b> select every single f**king HU on this planet.
+	 */
+	@Test
+	public void testEmptyHUIdsCollection()
+	{
+		final DocumentFilter noHusFilter = HUIdsFilterHelper.createFilter(ImmutableList.of());
+		final String sql = HUIdsFilterHelper.SQL_DOCUMENT_FILTER_CONVERTER.getSql(SqlParamsCollector.newInstance(), noHusFilter);
+
+		assertThat(sql).doesNotContain(HUIdsSqlDocumentFilterConverter.SQL_TRUE);
+	}
+
+}