org.eigenbase.relopt
Class CallingConvention

java.lang.Object
  org.eigenbase.relopt.CallingConvention

All Implemented Interfaces:

RelTrait

public class CallingConvention
extends Object
implements RelTrait

CallingConvention enumerates the calling conventions built in to the Saffron project. This set can be extended by applications by defining new instances of CallingConvention and registering them with a planner, along with the desired conversion rules. Extended ordinals must be greater than CallingConvention.enumeration.getMax().

Field Summary

static CallingConvention	ARRAY
static int	ARRAY_ORDINAL The ARRAY calling convention results in a Java expression which evaluates to an array containing the rows returned.
static CallingConvention	COLLECTION
static int	COLLECTION_ORDINAL The COLLECTION calling convention results in a Java expression which evaluates to a Collection, typically a ArrayList.
static CallingConvention	ENUMERATION
static int	ENUMERATION_ORDINAL
static CallingConvention	EXISTS
static int	EXISTS_ORDINAL The EXISTS calling convention is only allowed for a terminator.
static CallingConvention	HASHTABLE
static int	HASHTABLE_ORDINAL
private Class	interfaze Interface that a relational expression of this calling convention must implement.
static CallingConvention	ITERABLE
static int	ITERABLE_ORDINAL The ITERABLE calling convention means that the expression is converted to an openjava expression (Expression) which evalutes to an object which implements Iterable.
static CallingConvention	ITERATOR
static int	ITERATOR_ORDINAL The ITERATOR calling convention means that the expression is converted to an openjava expression (Expression) which evalutes to an TupleIter.
static CallingConvention	JAVA
static int	JAVA_ORDINAL The JAVA calling convention means that the expression is converted into an Openjava parse tree, which can then be un-parsed, compiled, and executed as java code.
static CallingConvention	MAP
static int	MAP_ORDINAL
private static int	maxOrdinal
private String	name Enumerated value's name.
static CallingConvention	NONE
static int	NONE_ORDINAL The NONE calling convention means that expression does not support any calling convention -- in other words, it is not implementable, and has to be transformed to something else in order to be implemented.
private int	ordinal Enumerated value's ordinal.
static CallingConvention	RESULT_SET
static int	RESULT_SET_ORDINAL The RESULT_SET calling convention means that the expression is a JDBC result set.
static CallingConvention[]	values
static CallingConvention	VECTOR
static int	VECTOR_ORDINAL

Constructor Summary

CallingConvention(String name, int ordinal, Class interfaze)

Method Summary

boolean	equals(Object o) Compares this CallingConvention to another for equality by ordinal.
static int	generateOrdinal()
Class	getInterface()
String	getName()
int	getOrdinal()
RelTraitDef	getTraitDef() Returns the RelTraitDef that defines this RelTrait.
int	hashCode() Returns the ordinal as the CallingConvention's hash code.
String	toString() Returns the value's name.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

maxOrdinal

private static int maxOrdinal

NONE_ORDINAL

public static final int NONE_ORDINAL

The NONE calling convention means that expression does not support any calling convention -- in other words, it is not implementable, and has to be transformed to something else in order to be implemented.

See Also:

Constant Field Values

NONE

public static final CallingConvention NONE

JAVA_ORDINAL

public static final int JAVA_ORDINAL

The JAVA calling convention means that the expression is converted into an Openjava parse tree, which can then be un-parsed, compiled, and executed as java code.

The JavaRel.implement(org.eigenbase.oj.rel.JavaRelImplementor) method generates a piece of code which will call the piece of code corresponding to the parent once for each row:

• The parent code is generated by calling JavaRelImplementor.generateParentBody(org.eigenbase.rel.RelNode, openjava.ptree.StatementList), which in turn calls JavaLoopRel.implementJavaParent(org.eigenbase.oj.rel.JavaRelImplementor, int) on the parent.
• The code is generated into the current block (gleaned from JavaRelImplementor.getStatementList()).

See Also:

Constant Field Values

JAVA

public static final CallingConvention JAVA

ITERATOR_ORDINAL

public static final int ITERATOR_ORDINAL

The ITERATOR calling convention means that the expression is converted to an openjava expression (Expression) which evalutes to an TupleIter. See ConverterRel.

See Also:

Constant Field Values

ITERATOR

public static final CallingConvention ITERATOR

ARRAY_ORDINAL

public static final int ARRAY_ORDINAL

The ARRAY calling convention results in a Java expression which evaluates to an array containing the rows returned. Compare with JAVA_ORDINAL, where a loop does something for each row returned).

See Also:

Constant Field Values

ARRAY

public static final CallingConvention ARRAY

COLLECTION_ORDINAL

public static final int COLLECTION_ORDINAL

The COLLECTION calling convention results in a Java expression which evaluates to a Collection, typically a ArrayList.

See Also:

Constant Field Values

COLLECTION

public static final CallingConvention COLLECTION

VECTOR_ORDINAL

public static final int VECTOR_ORDINAL

See Also:

Constant Field Values

VECTOR

public static final CallingConvention VECTOR

ENUMERATION_ORDINAL

public static final int ENUMERATION_ORDINAL

See Also:

Constant Field Values

ENUMERATION

public static final CallingConvention ENUMERATION

MAP_ORDINAL

public static final int MAP_ORDINAL

See Also:

Constant Field Values

MAP

public static final CallingConvention MAP

HASHTABLE_ORDINAL

public static final int HASHTABLE_ORDINAL

See Also:

Constant Field Values

HASHTABLE

public static final CallingConvention HASHTABLE

ITERABLE_ORDINAL

public static final int ITERABLE_ORDINAL

The ITERABLE calling convention means that the expression is converted to an openjava expression (Expression) which evalutes to an object which implements Iterable.

See Also:

Constant Field Values

ITERABLE

public static final CallingConvention ITERABLE

EXISTS_ORDINAL

public static final int EXISTS_ORDINAL

The EXISTS calling convention is only allowed for a terminator.

See Also:

Constant Field Values

EXISTS

public static final CallingConvention EXISTS

RESULT_SET_ORDINAL

public static final int RESULT_SET_ORDINAL

The RESULT_SET calling convention means that the expression is a JDBC result set. When a result set is converted to another convention such as array or iterator, the default object type is Row.

See Also:

Constant Field Values

RESULT_SET

public static final CallingConvention RESULT_SET

values

public static final CallingConvention[] values

name

private final String name

Enumerated value's name.

ordinal

private final int ordinal

Enumerated value's ordinal.

interfaze

private final Class interfaze

Interface that a relational expression of this calling convention must implement. Must be a sub-interface of RelNode.

Constructor Detail

CallingConvention

public CallingConvention(String name,
                         int ordinal,
                         Class interfaze)

Method Detail

getInterface

public Class getInterface()

generateOrdinal

public static int generateOrdinal()

getName

public String getName()

getOrdinal

public int getOrdinal()

getTraitDef

public RelTraitDef getTraitDef()

Description copied from interface: RelTrait

Returns the RelTraitDef that defines this RelTrait.

Specified by:

getTraitDef in interface RelTrait

Returns:

the RelTraitDef that defines this RelTrait

hashCode

public int hashCode()

Returns the ordinal as the CallingConvention's hash code.

Specified by:

hashCode in interface RelTrait

Overrides:

hashCode in class Object

Returns:

ordinal

equals

public boolean equals(Object o)

Compares this CallingConvention to another for equality by ordinal.

Specified by:

equals in interface RelTrait

Overrides:

equals in class Object

Parameters:

o - the other CallingConvention

Returns:

true if they are equal, false otherwise

toString

public String toString()

Returns the value's name.

Specified by:

toString in interface RelTrait

Overrides:

toString in class Object