fix: filter limit constant (#787)

* fix: filter limit constant

Should 20 KB not 20 MB

* fix test

Author: igorbernstein2

google-cloud-bigtable/src/main/java/com/google/cloud/bigtable/data/v2/models/Query.java

@@ -43,8 +43,8 @@
 public final class Query implements Serializable {
   private static final long serialVersionUID = -316972783499434755L;
 
-  // bigtable can server the largest filter size of 20MB.
-  private static final int MAX_FILTER_SIZE = 20 * 1024 * 1024;
+  // bigtable can server the largest filter size of 20KB.
+  private static final int MAX_FILTER_SIZE = 20 * 1024;
 
   private final String tableId;
   private transient ReadRowsRequest.Builder builder = ReadRowsRequest.newBuilder();
@@ -170,7 +170,7 @@ public Query filter(Filters.Filter filter) {
 
     RowFilter rowFilter = filter.toProto();
     Preconditions.checkArgument(
-        rowFilter.getSerializedSize() < MAX_FILTER_SIZE, "filter size can't be more than 20MB");
+        rowFilter.getSerializedSize() < MAX_FILTER_SIZE, "filter size can't be more than 20KB");
 
     builder.setFilter(rowFilter);
     return this;

google-cloud-bigtable/src/test/java/com/google/cloud/bigtable/data/v2/models/QueryTest.java

@@ -123,15 +123,15 @@ public void filterTestWithExceptions() {
     assertThat(actualException).isInstanceOf(NullPointerException.class);
 
     actualException = null;
-    int maxFilterSize = 20 * 1024 * 1024;
+    int maxFilterSize = 20 * 1024;
     ByteString largeValue = ByteString.copyFrom(new byte[maxFilterSize + 1]);
 
     try {
       Query.create(TABLE_ID).filter(FILTERS.value().exactMatch(largeValue));
     } catch (Exception ex) {
       actualException = ex;
     }
-    assertThat(actualException).hasMessageThat().contains("filter size can't be more than 20MB");
+    assertThat(actualException).hasMessageThat().contains("filter size can't be more than 20KB");
   }
 
   @Test