net.sf.saffron.rex
Class RexBuilder

java.lang.Object
  |
  +--net.sf.saffron.rex.RexBuilder

Direct Known Subclasses:

JavaRexBuilder

public class RexBuilder

extends Object

Factory for row expressions.

Some common literal values (NULL, TRUE, FALSE, 0, 1, '') are cached.

Since:

Nov 23, 2003

Version:

$Id: $

Author:

jhyde

Field Summary

private RexLiteral	booleanFalse
private RexLiteral	booleanTrue
private RexLiteral	constantNull
private RexLiteral	integerOne
private RexLiteral	integerZero
SqlOperatorTable	operatorTable
protected SaffronTypeFactory	typeFactory
private RexLiteral	varcharEmpty

Constructor Summary

protected

RexBuilder(SaffronTypeFactory typeFactory)

Method Summary

RexLiteral	constantNull() Creates a constant for the SQL NULL value.
SqlOperator	getOperator(RexKind kind, RexNode[] args) Chooses an appropriate operator to implement a RexKind, given a specific number and types of arguments.
SaffronTypeFactory	getTypeFactory()
private SaffronType[]	getTypes(RexNode[] exprs)
RexNode	makeCall(RexKind kind, RexNode arg0) Creates a call with 1 argument, converting a RexKind to an appropriate SqlOperator.
RexNode	makeCall(RexKind kind, RexNode[] args) Creates a call with an array of arguments, converting a RexKind to an appropriate SqlOperator.
RexNode	makeCall(RexKind kind, RexNode arg0, RexNode arg1) Creates a call with 2 arguments, converting a RexKind to an appropriate SqlOperator.
RexNode	makeCall(SqlOperator op, RexNode[] exprs) Creates a call with an array of arguments.
RexNode	makeCall(SqlOperator op, RexNode expr0, RexNode expr1) Creates a call with 2 arguments.
RexNode	makeCast(SaffronType type, RexNode exp)
RexNode	makeCorrel(SaffronType type, String name)
RexNode	makeFieldAccess(RexNode expr, int i)
RexNode	makeFieldAccess(RexNode expr, String fieldName)
private RexNode	makeFieldAccessInternal(RexNode expr, SaffronField field)
RexNode	makeInputRef(SaffronType type, int i)
RexLiteral	makeLiteral(boolean b) Creates a boolean literal.
RexLiteral	makeLiteral(Date date) Creates a Date literal.
RexLiteral	makeLiteral(double d) Creates a double-precision literal.
RexLiteral	makeLiteral(long i) Creates an integer literal.
protected RexLiteral	makeLiteral(Object o, SaffronType type)
RexLiteral	makeLiteral(String s) Creates a varchar literal.
RexLiteral	makeLiteral(Time time) Creates a Time literal.
RexLiteral	makeLiteral(Timestamp timestamp) Creates a Timestamp literal.
RexNode	makeRangeReference(SaffronType rowType) Creates a reference to all the fields in the row.
RexNode	makeRangeReference(SaffronType type, int i) Creates a reference to all the fields in the row.

Methods inherited from class java.lang.Object

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

Field Detail

typeFactory

protected final SaffronTypeFactory typeFactory

booleanTrue

private final RexLiteral booleanTrue

booleanFalse

private final RexLiteral booleanFalse

integerZero

private final RexLiteral integerZero

integerOne

private final RexLiteral integerOne

varcharEmpty

private final RexLiteral varcharEmpty

constantNull

private final RexLiteral constantNull

operatorTable

public final SqlOperatorTable operatorTable

Constructor Detail

RexBuilder

protected RexBuilder(SaffronTypeFactory typeFactory)

Method Detail

getTypeFactory

public SaffronTypeFactory getTypeFactory()

makeFieldAccess

public RexNode makeFieldAccess(RexNode expr,
                               String fieldName)

makeFieldAccess

public RexNode makeFieldAccess(RexNode expr,
                               int i)

makeFieldAccessInternal

private RexNode makeFieldAccessInternal(RexNode expr,
                                        SaffronField field)

makeCall

public RexNode makeCall(RexKind kind,
                        RexNode arg0)

Creates a call with 1 argument, converting a RexKind to an appropriate SqlOperator.

makeCall

public RexNode makeCall(RexKind kind,
                        RexNode[] args)

Creates a call with an array of arguments, converting a RexKind to an appropriate SqlOperator.

makeCall

public RexNode makeCall(RexKind kind,
                        RexNode arg0,
                        RexNode arg1)

Creates a call with 2 arguments, converting a RexKind to an appropriate SqlOperator.

makeCall

public RexNode makeCall(SqlOperator op,
                        RexNode expr0,
                        RexNode expr1)

Creates a call with 2 arguments.

makeCall

public RexNode makeCall(SqlOperator op,
                        RexNode[] exprs)

Creates a call with an array of arguments.

This is the fundamental method called by all of the other makeCall methods. If you derive a class from RexBuilder, this is the only method you need to override.

getTypes

private SaffronType[] getTypes(RexNode[] exprs)

getOperator

public SqlOperator getOperator(RexKind kind,
                               RexNode[] args)

Chooses an appropriate operator to implement a RexKind, given a specific number and types of arguments.

constantNull

public RexLiteral constantNull()

Creates a constant for the SQL NULL value.

makeCorrel

public RexNode makeCorrel(SaffronType type,
                          String name)

makeCast

public RexNode makeCast(SaffronType type,
                        RexNode exp)

makeRangeReference

public RexNode makeRangeReference(SaffronType rowType)

Creates a reference to all the fields in the row. That is, the whole row as a single record object.

Parameters:

rowType - Type of the input row

makeRangeReference

public RexNode makeRangeReference(SaffronType type,
                                  int i)

Creates a reference to all the fields in the row. For example, if the input row has type T{f0,f1,f2,f3,f4} then makeRangeReference(T{f0,f1,f2,f3,f4}, S{f3,f4}, 3) is an expression which yields the last 2 fields.

Parameters:

type - Type of the resulting range record.

i - Index of first field

makeInputRef

public RexNode makeInputRef(SaffronType type,
                            int i)

makeLiteral

protected RexLiteral makeLiteral(Object o,
                                 SaffronType type)

makeLiteral

public RexLiteral makeLiteral(boolean b)

Creates a boolean literal.

makeLiteral

public RexLiteral makeLiteral(long i)

Creates an integer literal.

makeLiteral

public RexLiteral makeLiteral(double d)

Creates a double-precision literal.

makeLiteral

public RexLiteral makeLiteral(String s)

Creates a varchar literal.

Pre-condition:

s != null

makeLiteral

public RexLiteral makeLiteral(Date date)

Creates a Date literal.

Pre-condition:

date != null

makeLiteral

public RexLiteral makeLiteral(Time time)

Creates a Time literal.

Pre-condition:

time != null

makeLiteral

public RexLiteral makeLiteral(Timestamp timestamp)

Creates a Timestamp literal.

Pre-condition:

timestamp != null