Extend Filters, extract Ids

oshdb-filter/src/main/java/org/heigit/ohsome/oshdb/filter/ChangesetIdFilterEqualsAnyOf.java

@@ -14,11 +14,13 @@
  * A filter which selects OSM contributions by matching to a list of changeset ids.
  */
 public class ChangesetIdFilterEqualsAnyOf extends NegatableFilter {
-  private final Collection<Long> changesetIdList;
+  private final Collection<Long> changesetIds;
 
   ChangesetIdFilterEqualsAnyOf(@Nonnull Collection<Long> changesetIdList) {
+    this(new HashSet<>(changesetIdList));
+  }
+  ChangesetIdFilterEqualsAnyOf(@Nonnull Set<Long> changesetIds) {
     super(new FilterInternal() {
-      private final Set<Long> changesetIds = new HashSet<>(changesetIdList);
 
       @Override
       public boolean applyOSH(OSHEntity entity) {
@@ -37,15 +39,15 @@ public boolean applyOSMEntitySnapshot(OSMEntitySnapshot ignored) {
 
       @Override
       public String toString() {
-        return "changeset:in(" + changesetIdList.stream().map(String::valueOf)
+        return "changeset:in(" + changesetIds.stream().map(String::valueOf)
             .collect(Collectors.joining(",")) + ")";
       }
     });
-    this.changesetIdList = changesetIdList;
+    this.changesetIds = changesetIds;
   }
 
   @Contract(pure = true)
   public Collection<Long> getChangesetIdList() {
-    return this.changesetIdList;
+    return this.changesetIds;
   }
 }

oshdb-filter/src/main/java/org/heigit/ohsome/oshdb/filter/ChangesetIdFilterRange.java

@@ -8,6 +8,8 @@
  * A filter which selects OSM contributions by matching to a range of changeset ids.
  */
 public class ChangesetIdFilterRange extends NegatableFilter {
+  private final IdRange changesetIdRange;
+
   ChangesetIdFilterRange(IdRange changesetIdRange) {
     super(new FilterInternal() {
       @Override
@@ -30,5 +32,10 @@ public String toString() {
         return "changeset:in-range" + changesetIdRange;
       }
     });
+    this.changesetIdRange = changesetIdRange;
+  }
+
+  public IdRange getChangesetIdRange() {
+    return changesetIdRange;
   }
 }

oshdb-filter/src/main/java/org/heigit/ohsome/oshdb/filter/FilterExpression.java

@@ -81,7 +81,7 @@ default boolean applyOSMGeometry(OSMEntity entity, Geometry geometry) {
    * Apply a filter to a snapshot ({@link OSMEntitySnapshot}) of an OSM entity.
    *
    * @param snapshot a snapshot of the OSM entity to check
-   * @return true if the the OSM entity snapshot fulfills the specified filter, otherwise false.
+   * @return true if the OSM entity snapshot fulfills the specified filter, otherwise false.
    */
   @Contract(pure = true)
   default boolean applyOSMEntitySnapshot(OSMEntitySnapshot snapshot) {
@@ -95,7 +95,7 @@ default boolean applyOSMEntitySnapshot(OSMEntitySnapshot snapshot) {
    * modification or the state of it after the modification matches the filter.</p>
    *
    * @param contribution a modification of the OSM entity to check
-   * @return true if the the OSM contribution fulfills the specified filter, otherwise false.
+   * @return true if the OSM contribution fulfills the specified filter, otherwise false.
    */
   @Contract(pure = true)
   default boolean applyOSMContribution(OSMContribution contribution) {
@@ -133,11 +133,11 @@ default boolean applyOSMContribution(OSMContribution contribution) {
    */
   @Contract(pure = true)
   default List<List<Filter>> normalize() {
-    if (this instanceof Filter) {
-      return Collections.singletonList(Collections.singletonList((Filter) this));
-    } else if (this instanceof AndOperator) {
-      List<List<Filter>> exp1 = ((BinaryOperator) this).getLeftOperand().normalize();
-      List<List<Filter>> exp2 = ((BinaryOperator) this).getRightOperand().normalize();
+    if (this instanceof Filter filter) {
+      return Collections.singletonList(Collections.singletonList(filter));
+    } else if (this instanceof AndOperator operator) {
+      List<List<Filter>> exp1 = operator.getLeftOperand().normalize();
+      List<List<Filter>> exp2 = operator.getRightOperand().normalize();
       // return cross product of exp1 and exp2
       List<List<Filter>> combined = new LinkedList<>();
       for (List<Filter> e1 : exp1) {
@@ -149,9 +149,9 @@ default List<List<Filter>> normalize() {
         }
       }
       return combined;
-    } else if (this instanceof OrOperator) {
-      List<List<Filter>> exp1 = ((BinaryOperator) this).getLeftOperand().normalize();
-      List<List<Filter>> exp2 = ((BinaryOperator) this).getRightOperand().normalize();
+    } else if (this instanceof OrOperator operator) {
+      List<List<Filter>> exp1 = operator.getLeftOperand().normalize();
+      List<List<Filter>> exp2 = operator.getRightOperand().normalize();
       List<List<Filter>> combined = new ArrayList<>(exp1.size() + exp2.size());
       combined.addAll(exp1);
       combined.addAll(exp2);

oshdb-filter/src/main/java/org/heigit/ohsome/oshdb/filter/FilterUtil.java

@@ -0,0 +1,39 @@
+package org.heigit.ohsome.oshdb.filter;
+
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+
+import static java.util.Collections.emptySet;
+
+public class FilterUtil {
+
+    private FilterUtil() {
+        // utility class
+    }
+
+    public static Set<Long> ids(FilterExpression expression) {
+        return ids(expression.normalize());
+    }
+
+    public static Set<Long> ids(List<List<Filter>> normalized) {
+        var ids = new HashSet<Long>();
+        for (var orGroups : normalized) {
+            var groupIds = new HashSet<Long>();
+            for (var filter: orGroups) {
+                if (filter instanceof IdFilterEquals equals){
+                    groupIds.add(equals.getId());
+                } else if (filter instanceof IdFilterEqualsAnyOf equalsAnyOf) {
+                    groupIds.addAll(equalsAnyOf.getIds());
+                } else if (filter instanceof IdFilterRange range) {
+                    range.getRange().getIds().forEach(groupIds::add);
+                }
+            }
+            if (groupIds.isEmpty()) {
+                return emptySet();
+            }
+            ids.addAll(groupIds);
+        }
+        return ids;
+    }
+}

oshdb-filter/src/main/java/org/heigit/ohsome/oshdb/filter/IdFilterEqualsAnyOf.java

@@ -12,13 +12,19 @@
  * A tag filter which executes a "id [not] in (id1, id2, …)" check.
  */
 public class IdFilterEqualsAnyOf extends NegatableFilter {
+
+  private final Set<Long> ids;
+
   IdFilterEqualsAnyOf(@Nonnull Collection<Long> idList) {
+    this(new HashSet<>(idList));
+  }
+
+  IdFilterEqualsAnyOf(@Nonnull Set<Long> ids) {
     super(new FilterInternal() {
-      private final Set<Long> ids = new HashSet<>(idList);
 
       @Override
       public boolean applyOSH(OSHEntity entity) {
-        return this.ids.contains(entity.getId());
+        return ids.contains(entity.getId());
       }
 
       @Override
@@ -28,7 +34,7 @@ boolean applyOSHNegated(OSHEntity entity) {
 
       @Override
       public boolean applyOSM(OSMEntity entity) {
-        return this.ids.contains(entity.getId());
+        return ids.contains(entity.getId());
       }
 
       @Override
@@ -38,12 +44,18 @@ boolean applyOSMNegated(OSMEntity entity) {
 
       @Override
       public String toString() {
-        return "id:in" + this.ids.stream().map(String::valueOf).collect(Collectors.joining(","));
+        return "id:in" + ids.stream().map(String::valueOf).collect(Collectors.joining(","));
       }
     });
 
-    if (idList.isEmpty()) {
+    if (ids.isEmpty()) {
       throw new IllegalStateException("list of ids must not be empty in a id in (list) filter");
     }
+
+    this.ids = ids;
+  }
+
+  public Set<Long> getIds() {
+    return ids;
   }
 }

oshdb-filter/src/main/java/org/heigit/ohsome/oshdb/filter/IdFilterRange.java

@@ -8,6 +8,8 @@
  * A filter which executes a "id [not] in range" check.
  */
 public class IdFilterRange extends NegatableFilter {
+  private final IdRange range;
+
   IdFilterRange(@Nonnull IdRange range) {
     super(new FilterInternal() {
       @Override
@@ -35,5 +37,10 @@ public String toString() {
         return "id:in-range" + range;
       }
     });
+    this.range = range;
+  }
+
+  public IdRange getRange() {
+    return range;
   }
 }

oshdb-filter/src/main/java/org/heigit/ohsome/oshdb/filter/IdRange.java

@@ -1,6 +1,7 @@
 package org.heigit.ohsome.oshdb.filter;
 
 import java.io.Serializable;
+import java.util.stream.LongStream;
 
 /**
  * Helper class to handle ranges of ids (incl. user ids, changeset ids, etc.).
@@ -34,4 +35,8 @@ public String toString() {
         + ".."
         + (toId == Long.MAX_VALUE ? "" : toId);
   }
+
+  public LongStream getIds() {
+    return LongStream.range(fromId, toId+1);
+  }
 }

oshdb-filter/src/main/java/org/heigit/ohsome/oshdb/filter/TagFilterAnyOf.java

@@ -12,19 +12,26 @@
  */
 abstract class TagFilterAnyOf implements Filter {
   final int keyId;
-  final Set<OSHDBTag> tags;
+  final HashSet<OSHDBTag> tags;
 
   TagFilterAnyOf(@Nonnull Collection<OSHDBTag> tags) {
     Optional<OSHDBTag> firstTag = tags.stream().findFirst();
-    if (!firstTag.isPresent()) {
-      throw new IllegalStateException("list of tags must not be empty in a key in (values) filter");
-    } else {
-      this.keyId = firstTag.get().getKey();
-      this.tags = new HashSet<>(tags);
-    }
+    this.keyId = firstTag
+            .orElseThrow(() -> new IllegalStateException("list of tags must not be empty in a key in (values) filter"))
+            .getKey();
+    this.tags = new HashSet<>(tags);
+
     if (!tags.stream().allMatch(tag -> tag.getKey() == this.keyId)) {
       throw new IllegalStateException(
           "list of tags must all share the same tag key in a key in (values) filter");
     }
   }
+
+  public int getKeyId() {
+    return keyId;
+  }
+
+  public Set<OSHDBTag> getTags() {
+    return tags;
+  }
 }

oshdb-filter/src/test/java/org/heigit/ohsome/oshdb/filter/FilterUtilTest.java

@@ -0,0 +1,30 @@
+package org.heigit.ohsome.oshdb.filter;
+
+import org.junit.jupiter.api.Test;
+
+import java.util.Set;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+class FilterUtilTest extends FilterTest{
+
+    @Test
+    void extractIds() {
+        extractIds("id:123", Set.of(123L));
+        extractIds("id:123 or id:234", Set.of(123L, 234L));
+        extractIds("id:123 and not id:234", Set.of(123L));
+        extractIds("id:123 or name=heigit", Set.of());
+        extractIds("id:(123, 234)", Set.of(123L, 234L));
+        extractIds("id:(123 .. 125)", Set.of(123L, 124L, 125L));
+    }
+
+    private void extractIds(String filter, Set<Long> expected) {
+       var expression = parser.parse(filter);
+       var actual = FilterUtil.ids(expression);
+
+       assertEquals(expected.size(), actual.size());
+       assertTrue(expected.containsAll(actual));
+    }
+
+}