net.sf.saffron.rex
Class RexKind

java.lang.Object
  |
  +--net.sf.saffron.util.EnumeratedValues.BasicValue
        |
        +--net.sf.saffron.rex.RexKind

All Implemented Interfaces:

EnumeratedValues.Value

public class RexKind

extends EnumeratedValues.BasicValue

Enumeration of some important types of row-expression.

The values are immutable, canonical constants, so you can use Kinds to find particular types of expressions quickly. To identity a call to a common operator such as '=', use RexNode.isA(net.sf.saffron.rex.RexKind):

exp.isA(RexKind.Equals)

To identify a category of expressions, you can use RexNode.isA(net.sf.saffron.rex.RexKind) with an aggregate RexKind. The following expression will return true for calls to '=' and '>=', but false for the constant '5', or a call to '+':

exp.isA(RexKind.Comparison)

To quickly choose between a number of options, use the ordinal property:

switch (exp.getKind().getOrdinal()) {
 case RexKind.Equals_ORDINAL:
     ...;
 case RexKind.NotEquals_ORDINAL:
     ...;
 default:
     throw exp.getKind().unexpected();
 }

Since:

Nov 24, 2003

Version:

$Id: $

Author:

jhyde

Field Summary

static RexKind	And The logical "AND" operator.
static int	AndORDINAL
static RexKind	Arithmetic An arithmetic operator (Divide, Minus, MinusPrefix, Plus, Times).
static int	ArithmeticORDINAL
static RexKind	Comparison A comparison operator (Equals, GreaterThan, etc.).
static int	ComparisonORDINAL
static RexKind	Concat The string concatenation operator, "||".
static int	ConcatORDINAL
static RexKind	Divide The arithmetic division operator, "/".
static int	DivideORDINAL
static EnumeratedValues	enumeration Set of all RexKind instances.
static RexKind	Equals The equals operator, "=".
static int	EqualsORDINAL
static RexKind	FieldAccess The arithmetic multiplication operator, "*".
static int	FieldAccessORDINAL
static int	GreaterEqualORDINAL
static RexKind	GreaterThan The greater-than operator, ">".
static int	GreaterThanORDINAL
static RexKind	GreaterThanOrEqual The greater-than-or-equal operator, ">=".
static RexKind	Identifier An identifier.
static int	IdentifierORDINAL
static RexKind	IsNull The IS NULL operator.
static int	IsNullORDINAL
static RexKind	LessThan The less-than operator, "<".
static int	LessThanORDINAL
static RexKind	LessThanOrEqual The less-than-or-equal operator, "<=".
static int	LessThanOrEqualORDINAL
static RexKind	Literal A literal.
static int	LiteralORDINAL
static RexKind	Logical A logical operator (And, Or, Not).
static int	LogicalORDINAL
static RexKind	Minus The arithmetic minus operator, "-".
static int	MinusORDINAL
static RexKind	MinusPrefix The unary minus operator, as in "-1".
static int	MinusPrefixORDINAL
static RexKind	Not The logical "NOT" operator.
static RexKind	NotEquals The not-equals operator, "!=" or "<>".
static int	NotEqualsORDINAL
static int	NotORDINAL
static RexKind	Or The logical "OR" operator.
static int	OrORDINAL
static RexKind	Other No operator in particular.
private Set	otherKinds
static int	OtherORDINAL
static RexKind	Plus The arithmetic plus operator, "+".
static int	PlusORDINAL
static RexKind	Row The row constructor operator.
static int	RowORDINAL
static RexKind	Substr The substring function.
static int	SubstrORDINAL
static RexKind	Times The arithmetic multiplication operator, "*".
static int	TimesORDINAL
static RexKind	Values The VALUES operator.
static int	ValuesORDINAL

Fields inherited from class net.sf.saffron.util.EnumeratedValues.BasicValue

description_, name_, ordinal_

Constructor Summary

private	RexKind(String name, int ordinal) Creates a kind.
private	RexKind(String name, int ordinal, RexKind[] others) Creates a kind which includes other kinds.

Method Summary

static RexKind	get(int ordinal) Looks up a kind from its ordinal.
static RexKind	get(String name) Looks up a kind from its name.
boolean	includes(RexKind kind)

Methods inherited from class net.sf.saffron.util.EnumeratedValues.BasicValue

equals, getDescription, getName, getOrdinal, toString, unexpected

Methods inherited from class java.lang.Object

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

Field Detail

otherKinds

private Set otherKinds

OtherORDINAL

public static final int OtherORDINAL

See Also:

Constant Field Values

Other

public static final RexKind Other

No operator in particular. This is the default kind.

EqualsORDINAL

public static final int EqualsORDINAL

See Also:

Constant Field Values

Equals

public static final RexKind Equals

The equals operator, "=".

NotEqualsORDINAL

public static final int NotEqualsORDINAL

See Also:

Constant Field Values

NotEquals

public static final RexKind NotEquals

The not-equals operator, "!=" or "<>".

GreaterThanORDINAL

public static final int GreaterThanORDINAL

See Also:

Constant Field Values

GreaterThan

public static final RexKind GreaterThan

The greater-than operator, ">".

GreaterEqualORDINAL

public static final int GreaterEqualORDINAL

See Also:

Constant Field Values

GreaterThanOrEqual

public static final RexKind GreaterThanOrEqual

The greater-than-or-equal operator, ">=".

LessThanORDINAL

public static final int LessThanORDINAL

See Also:

Constant Field Values

LessThan

public static final RexKind LessThan

The less-than operator, "<".

LessThanOrEqualORDINAL

public static final int LessThanOrEqualORDINAL

See Also:

Constant Field Values

LessThanOrEqual

public static final RexKind LessThanOrEqual

The less-than-or-equal operator, "<=".

ComparisonORDINAL

public static final int ComparisonORDINAL

See Also:

Constant Field Values

Comparison

public static final RexKind Comparison

A comparison operator (Equals, GreaterThan, etc.). Comparisons are always a RexCall with 2 arguments.

AndORDINAL

public static final int AndORDINAL

See Also:

Constant Field Values

And

public static final RexKind And

The logical "AND" operator.

OrORDINAL

public static final int OrORDINAL

See Also:

Constant Field Values

Or

public static final RexKind Or

The logical "OR" operator.

NotORDINAL

public static final int NotORDINAL

See Also:

Constant Field Values

Not

public static final RexKind Not

The logical "NOT" operator.

LogicalORDINAL

public static final int LogicalORDINAL

See Also:

Constant Field Values

Logical

public static final RexKind Logical

A logical operator (And, Or, Not).

DivideORDINAL

public static final int DivideORDINAL

See Also:

Constant Field Values

Divide

public static final RexKind Divide

The arithmetic division operator, "/".

MinusORDINAL

public static final int MinusORDINAL

See Also:

Constant Field Values

Minus

public static final RexKind Minus

The arithmetic minus operator, "-".

See Also:

MinusPrefix

PlusORDINAL

public static final int PlusORDINAL

See Also:

Constant Field Values

Plus

public static final RexKind Plus

The arithmetic plus operator, "+".

MinusPrefixORDINAL

public static final int MinusPrefixORDINAL

See Also:

Constant Field Values

MinusPrefix

public static final RexKind MinusPrefix

The unary minus operator, as in "-1".

See Also:

Minus

TimesORDINAL

public static final int TimesORDINAL

See Also:

Constant Field Values

Times

public static final RexKind Times

The arithmetic multiplication operator, "*".

ArithmeticORDINAL

public static final int ArithmeticORDINAL

See Also:

Constant Field Values

Arithmetic

public static final RexKind Arithmetic

An arithmetic operator (Divide, Minus, MinusPrefix, Plus, Times).

FieldAccessORDINAL

public static final int FieldAccessORDINAL

See Also:

Constant Field Values

FieldAccess

public static final RexKind FieldAccess

The arithmetic multiplication operator, "*".

ConcatORDINAL

public static final int ConcatORDINAL

See Also:

Constant Field Values

Concat

public static final RexKind Concat

The string concatenation operator, "||".

SubstrORDINAL

public static final int SubstrORDINAL

See Also:

Constant Field Values

Substr

public static final RexKind Substr

The substring function.

RowORDINAL

public static final int RowORDINAL

See Also:

Constant Field Values

Row

public static final RexKind Row

The row constructor operator.

IsNullORDINAL

public static final int IsNullORDINAL

See Also:

Constant Field Values

IsNull

public static final RexKind IsNull

The IS NULL operator. (There is no "IS NOT NULL" operator.)

IdentifierORDINAL

public static final int IdentifierORDINAL

See Also:

Constant Field Values

Identifier

public static final RexKind Identifier

An identifier.

LiteralORDINAL

public static final int LiteralORDINAL

See Also:

Constant Field Values

Literal

public static final RexKind Literal

A literal.

ValuesORDINAL

public static final int ValuesORDINAL

See Also:

Constant Field Values

Values

public static final RexKind Values

The VALUES operator.

enumeration

public static final EnumeratedValues enumeration

Set of all RexKind instances.

Constructor Detail

RexKind

private RexKind(String name,
                int ordinal)

Creates a kind.

RexKind

private RexKind(String name,
                int ordinal,
                RexKind[] others)

Creates a kind which includes other kinds.

Method Detail

includes

public boolean includes(RexKind kind)

get

public static RexKind get(int ordinal)

Looks up a kind from its ordinal.

get

public static RexKind get(String name)

Looks up a kind from its name.