Package com.amazonaws.athena.connectors.jdbc.manager

Class FederationExpressionParser

java.lang.Object

com.amazonaws.athena.connectors.jdbc.manager.FederationExpressionParser

Direct Known Subclasses:

BigQueryFederationExpressionParser, DefaultJdbcFederationExpressionParser, JdbcFederationExpressionParser

public abstract class FederationExpressionParser
extends Object

Constructor Summary

Constructors

Constructor	Description
FederationExpressionParser()

Method Summary

Modifier and Type	Method	Description
abstract String	mapFunctionToDataSourceSyntax(FunctionName functionName, org.apache.arrow.vector.types.pojo.ArrowType type, List<String> arguments)	Each datasource has different syntax for various operations, quotes, etc.
List<String>	parseComplexExpressions(List<org.apache.arrow.vector.types.pojo.Field> columns, Constraints constraints, List<TypeAndValue> accumulator)
String	parseConstantExpression(ConstantExpression constantExpression, List<TypeAndValue> accumulator)
String	parseFunctionCallExpression(FunctionCallExpression functionCallExpression, List<TypeAndValue> accumulator)	This is a recursive function, as function calls can have arguments which, themselves, are function calls.
String	parseVariableExpression(VariableExpression variableExpression)	Various connectors have different standards for wrapping column names in some specific quote character.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

FederationExpressionParser

public FederationExpressionParser()

Method Detail

mapFunctionToDataSourceSyntax

public abstract String mapFunctionToDataSourceSyntax(FunctionName functionName,
                                                     org.apache.arrow.vector.types.pojo.ArrowType type,
                                                     List<String> arguments)

Each datasource has different syntax for various operations, quotes, etc. This is the only method a subclass to implement, and otherwise will just invoke parseComplexExpressions.

parseComplexExpressions

public List<String> parseComplexExpressions(List<org.apache.arrow.vector.types.pojo.Field> columns,
                                            Constraints constraints,
                                            List<TypeAndValue> accumulator)

parseFunctionCallExpression

public String parseFunctionCallExpression(FunctionCallExpression functionCallExpression,
                                          List<TypeAndValue> accumulator)

This is a recursive function, as function calls can have arguments which, themselves, are function calls.

Parameters:

functionCallExpression -

Returns:

parseConstantExpression

public String parseConstantExpression(ConstantExpression constantExpression,
                                      List<TypeAndValue> accumulator)

parseVariableExpression

public String parseVariableExpression(VariableExpression variableExpression)

Various connectors have different standards for wrapping column names in some specific quote character. This default implementation just returns the column name for connectors that don't have this specification.