Improve Query/Scan inference. Fix lint errors

Author: gusbro

gxdynamodb/src/main/java/com/genexus/db/dynamodb/DynamoDBErrors.java

@@ -3,5 +3,5 @@
 public class DynamoDBErrors
 {
 	public static final String ValidationException = "ValidationException";
-	public static CharSequence ValidationExceptionMessageKey = "The AttributeValue for a key attribute cannot contain an empty string value.";
+	public static final CharSequence ValidationExceptionMessageKey = "The AttributeValue for a key attribute cannot contain an empty string value.";
 }

gxdynamodb/src/main/java/com/genexus/db/dynamodb/DynamoDBPreparedStatement.java

@@ -16,12 +16,10 @@
 import java.sql.Connection;
 import java.sql.ResultSet;
 import java.sql.SQLException;
-import java.util.Arrays;
-import java.util.HashMap;
-import java.util.Iterator;
-import java.util.Map;
+import java.util.*;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
+import java.util.stream.Collectors;
 
 public class DynamoDBPreparedStatement extends ServicePreparedStatement
 {
@@ -50,6 +48,7 @@ public int executeUpdate() throws SQLException
 	}
 
 	private static final Pattern FILTER_PATTERN = Pattern.compile("\\((.*) = :(.*)\\)");
+	private static final Pattern VAR_PATTERN = Pattern.compile(".*(:.*)\\).*");
 	private int _executeQuery(DynamoDBResultSet resultSet) throws SQLException
 	{
 		query.initializeParms(parms);
@@ -59,9 +58,8 @@ private int _executeQuery(DynamoDBResultSet resultSet) throws SQLException
 
 		if(query.getQueryType() == QueryType.QUERY)
 		{
-			for (Iterator<VarValue> it = query.getVars().values().iterator(); it.hasNext(); )
+			for (VarValue var : query.getVars().values())
 			{
-				VarValue var = it.next();
 				values.put(var.name, DynamoDBHelper.toAttributeValue(var));
 			}
 		}
@@ -97,7 +95,7 @@ private int _executeQuery(DynamoDBResultSet resultSet) throws SQLException
 
 		if(query.getQueryType() != QueryType.QUERY)
 		{
-			for (String keyFilter : query.filters)
+			for (String keyFilter : query.getAllFilters().collect(Collectors.toList()))
 			{
 				Matcher match = FILTER_PATTERN.matcher(keyFilter);
 				if (match.matches() && match.groupCount() > 1)
@@ -115,17 +113,34 @@ private int _executeQuery(DynamoDBResultSet resultSet) throws SQLException
 		{
 			case QUERY:
 			{
+				boolean issueScan = query instanceof DynamoScan;
+				if (!issueScan)
+				{ // Check whether a query has to be demoted to scan due to empty parameters
+					for (String keyFilter : query.keyFilters)
+					{
+						Matcher match = VAR_PATTERN.matcher(keyFilter);
+						if (match.matches())
+						{
+							String varName = match.group(1);
+							VarValue varValue = query.getParm(varName);
+							if (varValue != null && varValue.value.toString().isEmpty())
+							{
+								issueScan = true;
+								break;
+							}
+						}
+					}
+				}
+
 				Iterator<HashMap<String, Object>> iterator;
-				if(query instanceof DynamoScan)
+				if(issueScan)
 				{
 					ScanRequest.Builder builder = ScanRequest.builder()
 						.tableName(query.tableName)
 						.projectionExpression(String.join(",", query.projection));
-					if(query.filters.length > 0)
-					{
-						builder.filterExpression(String.join(" AND ", query.filters))
-							.expressionAttributeValues(values);
-					}
+					String filterString = query.getAllFilters().collect(Collectors.joining(" AND "));
+					if(!filterString.isEmpty())
+						builder.filterExpression(filterString).expressionAttributeValues(values);
 					if(expressionAttributeNames != null)
 						builder.expressionAttributeNames(expressionAttributeNames);
 
@@ -139,11 +154,13 @@ private int _executeQuery(DynamoDBResultSet resultSet) throws SQLException
 				{
 					QueryRequest.Builder builder = QueryRequest.builder()
 						.tableName(query.tableName)
-						.keyConditionExpression(String.join(" AND ", query.filters))
+						.keyConditionExpression(String.join(" AND ", query.keyFilters))
 						.expressionAttributeValues(values)
 						.projectionExpression(String.join(", ", query.projection))
 						.indexName(query.getIndex())
 						.scanIndexForward(query.isScanIndexForward());
+					if(query.filters.length > 0)
+						builder.filterExpression(String.join(" AND ", query.filters));
 					if(expressionAttributeNames != null)
 						builder.expressionAttributeNames(expressionAttributeNames);
 
@@ -236,7 +253,7 @@ DynamoDbClient getClient() throws SQLException
 	}
 
 	@Override
-	public void setBinaryStream(int parameterIndex, InputStream x, int length) throws SQLException
+	public void setBinaryStream(int parameterIndex, InputStream x, int length)
 	{
 		parms[parameterIndex-1] = SdkBytes.fromInputStream(x);
 	}

gxdynamodb/src/main/java/com/genexus/db/dynamodb/DynamoDBResultSet.java

@@ -2,16 +2,12 @@
 
 import com.genexus.CommonUtil;
 import com.genexus.db.service.IOServiceContext;
-import com.genexus.db.service.ServiceError;
-import com.genexus.db.service.ServiceException;
 import com.genexus.db.service.ServiceResultSet;
-import org.apache.commons.lang.time.DateUtils;
 import software.amazon.awssdk.awscore.exception.AwsErrorDetails;
 import software.amazon.awssdk.core.SdkBytes;
 import software.amazon.awssdk.services.dynamodb.model.AttributeValue;
 import software.amazon.awssdk.services.dynamodb.model.DynamoDbException;
 
-import java.io.ByteArrayInputStream;
 import java.io.InputStream;
 import java.math.BigDecimal;
 import java.sql.SQLException;
@@ -114,7 +110,7 @@ private double getDecimal(int columnIndex)
 		.appendZoneRegionId()
 		.appendLiteral(']').toFormatter();
 
-	private static DateTimeFormatter US_DATE_TIME_OR_DATE = DateTimeFormatter.ofPattern("M/d/yyyy[ HH:mm:ss]");
+	private static final DateTimeFormatter US_DATE_TIME_OR_DATE = DateTimeFormatter.ofPattern("M/d/yyyy[ HH:mm:ss]");
 
 	private Instant getInstant(int columnIndex)
 	{

gxdynamodb/src/main/java/com/genexus/db/dynamodb/DynamoQuery.java

@@ -2,12 +2,23 @@
 
 import com.genexus.db.service.Query;
 
+import java.util.Arrays;
+import java.util.stream.Stream;
+
 public class DynamoQuery extends Query{
 	private String index;
 
 	private boolean scanIndexForward = true;
 	private static final String RANGE_KEY_INDEX = "RangeKey";
 	private String partitionKey;
+	public String[] keyFilters = EMPTY_ARR_STRING;
+
+	@Override
+	public DynamoQuery For(String tableName)
+	{
+		super.For(tableName);
+		return this;
+	}
 
 	@Override
 	public DynamoQuery orderBy(String index)
@@ -29,6 +40,12 @@ public DynamoQuery setKey(String partitionKey)
 		return this;
 	}
 
+	public DynamoQuery keyFilter(String[] keyFilters)
+	{
+		this.keyFilters = keyFilters;
+		return this;
+	}
+
 	public String getPartitionKey(){ return partitionKey; }
 
 	public DynamoQuery(DataStoreHelperDynamoDB dataStoreHelper)
@@ -47,4 +64,9 @@ public void setIndex(String index) {
 	public boolean isScanIndexForward() {
 		return scanIndexForward;
 	}
+
+	public Stream<String> getAllFilters()
+	{
+		return Stream.concat(Arrays.stream(keyFilters), Arrays.stream(filters));
+	}
 }

java/src/main/java/com/genexus/db/service/Query.java

@@ -3,11 +3,13 @@
 import com.genexus.util.NameValuePair;
 
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.HashMap;
 import java.util.Iterator;
+import java.util.stream.Stream;
 
 public class Query implements IQuery {
-	private static final String [] EMPTY_ARR_STRING = new String [0];
+	protected static final String [] EMPTY_ARR_STRING = new String [0];
 	final ServiceDataStoreHelper dataStoreHelper;
 	public Query(ServiceDataStoreHelper dataStoreHelper)
 	{