net.sf.farrago.ojrex
Class FarragoRexToOJTranslator

java.lang.Object
  org.eigenbase.oj.rex.RexToOJTranslator
      net.sf.farrago.ojrex.FarragoRexToOJTranslator

All Implemented Interfaces:

RexVisitor<Expression>

public class FarragoRexToOJTranslator
extends RexToOJTranslator

FarragoRexToOJTranslator refines RexToOJTranslator with Farrago-specifics.

NOTE jvs 22-June-2004: If you're scratching your head trying to understand the code generation methods in this package, it might help to look at examples of the generated code. One way to do this is by turning on FarragoTrace.getDynamicTracer() and then examining the code for generated classes after running queries. See also the .ref files under farrago/testlog/FarragoRexToOJTranslatorTest; these correspond to the test cases in FarragoRexToOJTranslatorTest. You can also add new test cases to that class, run the test, and examine the output.

Version:

$Id: //open/dev/farrago/src/net/sf/farrago/ojrex/FarragoRexToOJTranslator.java#32 $

Author:

John V. Sichi

Field Summary

private FarragoOJRexCastImplementor	castImplementor
private Map<Integer,String>	localRefMap
private MemberDeclarationList	memberList
private OJClass	ojNullablePrimitive
private FarragoRepos	repos
private StatementList	stmtList
private static String	TO_STRING_METHOD_NAME

Constructor Summary

FarragoRexToOJTranslator(FarragoRepos repos, JavaRelImplementor relImplementor, RelNode contextRel, OJRexImplementorTable implementorTable, StatementList stmtList, MemberDeclarationList memberList, RexProgram program)

FarragoRexToOJTranslator(FarragoRepos repos, JavaRelImplementor relImplementor, RelNode contextRel, OJRexImplementorTable implementorTable, StatementList stmtList, MemberDeclarationList memberList, RexProgram program, Map<Integer,String> localRefMap)
Creates a translator based on a OJRexImplementorTable.

Method Summary

void	addAssignmentStatement(StatementList stmtList, Expression funcResult, RelDataType retType, Variable varResult, boolean needCast)
void	addMember(MemberDeclaration member)
void	addStatement(Statement stmt)
void	addStatementsFromList(StatementList newStmtList)
Statement	assign(Expression lhs, Expression rhs) Generates a simple assignment statement
Expression	convertCastOrAssignment(String targetName, RelDataType lhsType, RelDataType rhsType, Expression lhsExp, Expression rhsExp)
Expression	convertCastOrAssignmentWithStmtList(StatementList stmtList, String targetName, RelDataType lhsType, RelDataType rhsType, Expression lhsExp, Expression rhsExp)
FieldAccess	convertFieldAccess(Variable variable, RelDataTypeField field)
Expression	convertPrimitiveAccess(Expression expr, RexNode op)
Expression	convertVariable(RelDataType type, String accessorName, ExpressionList accessorArgList)
Expression	convertVariableWithCast(RelDataType type, Class accessorClassCast, String accessorName, ExpressionList accessorArgList)
Expression	createNullTest(RexNode node, Expression originalOperand, Expression nullTest)
Variable	createPrimitiveScratchVariable(OJClass ojClass) Creates a primitive scratch variable without initialization.
Variable	createScratchVariable(OJClass ojClass, ExpressionList exprs, MemberDeclarationList mdlst)
Variable	createScratchVariable(RelDataType type)
Variable	createScratchVariableWithExpression(OJClass ojClass, Expression exp) Creates a member of this class with a given set of modifiers, and initializes it with an expression.
Statement	createSetNullStatement(Expression varResult, boolean isNull)
Statement	declareLocalVariable(OJClass ojClass, Variable var, Expression init) Generates a local variable declaration
FarragoTypeFactory	getFarragoTypeFactory()
FarragoRepos	getRepos()
Expression	isNull(Expression exp) Generates a boolean expression describing whether an input expression is null
boolean	isNullablePrimitive(RelDataType type)
FieldDeclaration	newMember(int modifiers, OJClass ojClass, Variable var, VariableInitializer init) Generates a declaration for a field in a class.
Variable	newVariable() Generates a variable with a unique name
FarragoRexToOJTranslator	push(StatementList stmtList) Returns a sub-translator to deal with a sub-block.
Statement	setIfNull(Variable var, Expression init) Generates a statement to initializes a variable if the variable is null
Expression	toString(Expression exp) Generates the string expression exp.toString()
void	translateAssignment(RelDataTypeField lhsField, Expression lhsExp, RexNode rhs) Generates code for an assignment.
OJClass	typeToOJClass(RelDataType type) Retrieves the OpenJava type corresponding to a Sql type
Expression	visitDynamicParam(RexDynamicParam dynamicParam)
Expression	visitLiteral(RexLiteral literal)
Expression	visitLocalRef(RexLocalRef localRef)

Methods inherited from class org.eigenbase.oj.rex.RexToOJTranslator

canConvertCall, convertByteArrayLiteral, convertByteArrayLiteralToInitializer, convertCall, getContextRel, getImplementorTable, getProgram, getRelImplementor, getSubStmtList, getTranslation, getTypeFactory, isInputRef, popProgram, pushProgram, setTranslation, translateRexNode, translateSubExpression, visitCall, visitCorrelVariable, visitFieldAccess, visitInputRef, visitOver, visitRangeRef

Methods inherited from class java.lang.Object

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

Field Detail

TO_STRING_METHOD_NAME

private static String TO_STRING_METHOD_NAME

repos

private final FarragoRepos repos

stmtList

private StatementList stmtList

memberList

private final MemberDeclarationList memberList

castImplementor

private final FarragoOJRexCastImplementor castImplementor

ojNullablePrimitive

private final OJClass ojNullablePrimitive

localRefMap

private final Map<Integer,String> localRefMap

Constructor Detail

FarragoRexToOJTranslator

public FarragoRexToOJTranslator(FarragoRepos repos,
                                JavaRelImplementor relImplementor,
                                RelNode contextRel,
                                OJRexImplementorTable implementorTable,
                                StatementList stmtList,
                                MemberDeclarationList memberList,
                                RexProgram program,
                                Map<Integer,String> localRefMap)

Creates a translator based on a OJRexImplementorTable.

Parameters:

repos - repository

relImplementor - implementation context

contextRel - relational expression which is the context for the row-expressions which are to be translated

implementorTable - table of implementations for SQL operators

stmtList - statement list for side-effects of translation

memberList - member list for class-level state required by

program - Program, may be null

localRefMap - map from RexLocalRef index to name of method which

FarragoRexToOJTranslator

public FarragoRexToOJTranslator(FarragoRepos repos,
                                JavaRelImplementor relImplementor,
                                RelNode contextRel,
                                OJRexImplementorTable implementorTable,
                                StatementList stmtList,
                                MemberDeclarationList memberList,
                                RexProgram program)

Method Detail

push

public FarragoRexToOJTranslator push(StatementList stmtList)

Description copied from class: RexToOJTranslator

Returns a sub-translator to deal with a sub-block.

The default implementation simply returns this translator. Other implementations may create a new translator which contains the expression-to-variable mappings of the sub-block.

Overrides:

push in class RexToOJTranslator

Parameters:

stmtList - Sub-block to generate code into

Returns:

A translator

addMember

public void addMember(MemberDeclaration member)

addStatement

public void addStatement(Statement stmt)

addStatementsFromList

public void addStatementsFromList(StatementList newStmtList)

visitLocalRef

public Expression visitLocalRef(RexLocalRef localRef)

Specified by:

visitLocalRef in interface RexVisitor<Expression>

Overrides:

visitLocalRef in class RexToOJTranslator

visitDynamicParam

public Expression visitDynamicParam(RexDynamicParam dynamicParam)

Specified by:

visitDynamicParam in interface RexVisitor<Expression>

Overrides:

visitDynamicParam in class RexToOJTranslator

convertVariable

public Expression convertVariable(RelDataType type,
                                  String accessorName,
                                  ExpressionList accessorArgList)

convertVariableWithCast

public Expression convertVariableWithCast(RelDataType type,
                                          Class accessorClassCast,
                                          String accessorName,
                                          ExpressionList accessorArgList)

visitLiteral

public Expression visitLiteral(RexLiteral literal)

Specified by:

visitLiteral in interface RexVisitor<Expression>

Overrides:

visitLiteral in class RexToOJTranslator

createScratchVariable

public Variable createScratchVariable(OJClass ojClass,
                                      ExpressionList exprs,
                                      MemberDeclarationList mdlst)

createScratchVariableWithExpression

public Variable createScratchVariableWithExpression(OJClass ojClass,
                                                    Expression exp)

Creates a member of this class with a given set of modifiers, and initializes it with an expression.

Parameters:

ojClass - Type of the variable

exp - Expression to initialize it

Returns:

Variable

createScratchVariable

public Variable createScratchVariable(RelDataType type)

createPrimitiveScratchVariable

public Variable createPrimitiveScratchVariable(OJClass ojClass)

Creates a primitive scratch variable without initialization.

Parameters:

ojClass - Variable's type

Returns:

scratch variable

newVariable

public Variable newVariable()

Generates a variable with a unique name

newMember

public FieldDeclaration newMember(int modifiers,
                                  OJClass ojClass,
                                  Variable var,
                                  VariableInitializer init)

Generates a declaration for a field in a class. This should be followed by addMember(openjava.ptree.MemberDeclaration).

Parameters:

modifiers - bitmap of modifiers such as private, or static

ojClass - type of the member

var - uniquely named variable

init - the initial value of the member, may be null

typeToOJClass

public OJClass typeToOJClass(RelDataType type)

Retrieves the OpenJava type corresponding to a Sql type

Parameters:

type - the Sql type

declareLocalVariable

public Statement declareLocalVariable(OJClass ojClass,
                                      Variable var,
                                      Expression init)

Generates a local variable declaration

Parameters:

ojClass - type of the variable

var - the uniquely named variable

init - the initial value of the variable, may be null

isNull

public Expression isNull(Expression exp)

Generates a boolean expression describing whether an input expression is null

Parameters:

exp - the input expression

toString

public Expression toString(Expression exp)

Generates the string expression exp.toString()

Parameters:

exp - expression to be converted into a string

assign

public Statement assign(Expression lhs,
                        Expression rhs)

Generates a simple assignment statement

Parameters:

lhs - the expression on left side of the assignment

rhs - the expression on the right side of the assignment

setIfNull

public Statement setIfNull(Variable var,
                           Expression init)

Generates a statement to initializes a variable if the variable is null

Parameters:

var - the variable to be initialed

init - the initial value for the variable

createSetNullStatement

public Statement createSetNullStatement(Expression varResult,
                                        boolean isNull)

createNullTest

public Expression createNullTest(RexNode node,
                                 Expression originalOperand,
                                 Expression nullTest)

isNullablePrimitive

public boolean isNullablePrimitive(RelDataType type)

convertFieldAccess

public FieldAccess convertFieldAccess(Variable variable,
                                      RelDataTypeField field)

convertPrimitiveAccess

public Expression convertPrimitiveAccess(Expression expr,
                                         RexNode op)

convertCastOrAssignmentWithStmtList

public Expression convertCastOrAssignmentWithStmtList(StatementList stmtList,
                                                      String targetName,
                                                      RelDataType lhsType,
                                                      RelDataType rhsType,
                                                      Expression lhsExp,
                                                      Expression rhsExp)

convertCastOrAssignment

public Expression convertCastOrAssignment(String targetName,
                                          RelDataType lhsType,
                                          RelDataType rhsType,
                                          Expression lhsExp,
                                          Expression rhsExp)

getFarragoTypeFactory

public FarragoTypeFactory getFarragoTypeFactory()

getRepos

public FarragoRepos getRepos()

translateAssignment

public void translateAssignment(RelDataTypeField lhsField,
                                Expression lhsExp,
                                RexNode rhs)

Description copied from class: RexToOJTranslator

Generates code for an assignment.

NOTE: This method is only implemented in translators which can generate sequences of statements. The default implementation of this method throws UnsupportedOperationException.

Overrides:

translateAssignment in class RexToOJTranslator

Parameters:

lhsField - target field

lhsExp - target field as OpenJava

rhs - the source expression (as RexNode)

addAssignmentStatement

public void addAssignmentStatement(StatementList stmtList,
                                   Expression funcResult,
                                   RelDataType retType,
                                   Variable varResult,
                                   boolean needCast)