org.apache.calcite.linq4j.tree

Class ClassDeclarationFinder

java.lang.Object

org.apache.calcite.linq4j.tree.Shuttle

org.apache.calcite.linq4j.tree.ClassDeclarationFinder

Direct Known Subclasses:

DeterministicCodeOptimizer

public class ClassDeclarationFinder
extends Shuttle

Entry point for optimizers that factor out deterministic expressions to final static fields. Instances of this class should not be reused, so new visitor should be created for optimizing a new expression tree.

Field Summary

Fields

Modifier and Type	Field and Description
protected List<MemberDeclaration>	addedDeclarations The list of new final static fields to be added to the current class.
protected @Nullable ClassDeclarationFinder	parent

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	ClassDeclarationFinder(ClassDeclarationFinder parent) Creates a child optimizer.

Method Summary

Modifier and Type	Method and Description
static ClassDeclarationFinder	create() Creates visitor that uses default optimizer.
static ClassDeclarationFinder	create(Class<? extends ClassDeclarationFinder> optimizingClass) Creates visitor that uses given class as optimizer.
static ClassDeclarationFinder	create(Function1<ClassDeclarationFinder,ClassDeclarationFinder> childFactory) Creates visitor that uses given factory to create optimizers.
protected @Nullable ParameterExpression	findDeclaredExpression(Expression expression) Finds if there exists ready for reuse declaration for given expression.
protected ClassDeclarationFinder	goDeeper() Creates child visitor.
protected boolean	hasField(String name) Verifies if the variable name is already in use.
protected boolean	isConstant(Expression expression) Verifies if the expression is effectively constant.
protected boolean	isConstant(Iterable<? extends Expression> list) Verifies if all the expressions in given list are effectively constant.
protected void	learnFinalStaticDeclarations(List<MemberDeclaration> memberDeclarations) Processes the list of declarations when class expression detected.
protected List<MemberDeclaration>	optimizeDeclarations(List<MemberDeclaration> memberDeclarations) Adds new declarations (e.g.
Shuttle	preVisit(ClassDeclaration classDeclaration) Creates optimizer local to the newly generated class.
Shuttle	preVisit(NewExpression newExpression) Creates optimizer local to the newly generated anonymous class.
protected Expression	tryOptimizeNewInstance(NewExpression newExpression) Optimizes new Type() constructs.
ClassDeclaration	visit(ClassDeclaration classDeclaration, List<MemberDeclaration> memberDeclarations)
Expression	visit(NewExpression newExpression, List<Expression> arguments, @Nullable List<MemberDeclaration> memberDeclarations)

Methods inherited from class org.apache.calcite.linq4j.tree.Shuttle

preVisit, preVisit, preVisit, preVisit, preVisit, preVisit, preVisit, preVisit, preVisit, preVisit, preVisit, preVisit, preVisit, preVisit, preVisit, preVisit, preVisit, preVisit, preVisit, preVisit, preVisit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit

Methods inherited from class java.lang.Object

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

Field Detail

parent

protected final @Nullable ClassDeclarationFinder parent

addedDeclarations

protected final List<MemberDeclaration> addedDeclarations

The list of new final static fields to be added to the current class.

Constructor Detail

ClassDeclarationFinder

protected ClassDeclarationFinder(ClassDeclarationFinder parent)

Creates a child optimizer. Typically a child is created for each class declaration, so each optimizer collects fields for exactly one class.

Parameters:

parent - parent optimizer

Method Detail

create

public static ClassDeclarationFinder create()

Creates visitor that uses default optimizer.

Returns:

optimizing visitor

create

public static ClassDeclarationFinder create(Class<? extends ClassDeclarationFinder> optimizingClass)

Creates visitor that uses given class as optimizer. The implementation should support (ClassDeclarationFinder) constructor.

Parameters:

optimizingClass - class that implements optimizations

Returns:

optimizing visitor

create

public static ClassDeclarationFinder create(Function1<ClassDeclarationFinder,ClassDeclarationFinder> childFactory)

Creates visitor that uses given factory to create optimizers.

Parameters:

childFactory - factory that creates optimizers

Returns:

optimizing visitor

preVisit

public Shuttle preVisit(NewExpression newExpression)

Creates optimizer local to the newly generated anonymous class.

Overrides:

preVisit in class Shuttle

Parameters:

newExpression - expression to optimize

Returns:

nested visitor if anonymous class is given

preVisit

public Shuttle preVisit(ClassDeclaration classDeclaration)

Creates optimizer local to the newly generated class.

Overrides:

preVisit in class Shuttle

Parameters:

classDeclaration - expression to optimize

Returns:

nested visitor

visit

public Expression visit(NewExpression newExpression,
                        List<Expression> arguments,
                        @Nullable List<MemberDeclaration> memberDeclarations)

Overrides:

visit in class Shuttle

learnFinalStaticDeclarations

protected void learnFinalStaticDeclarations(List<MemberDeclaration> memberDeclarations)

Processes the list of declarations when class expression detected. Sub-classes might figure out the existing fields for reuse.

Parameters:

memberDeclarations - list of declarations to process.

tryOptimizeNewInstance

protected Expression tryOptimizeNewInstance(NewExpression newExpression)

Optimizes new Type() constructs.

Parameters:

newExpression - expression to optimize

Returns:

always returns un-optimized expression

visit

public ClassDeclaration visit(ClassDeclaration classDeclaration,
                              List<MemberDeclaration> memberDeclarations)

Overrides:

visit in class Shuttle

optimizeDeclarations

protected List<MemberDeclaration> optimizeDeclarations(List<MemberDeclaration> memberDeclarations)

Adds new declarations (e.g. final static fields) to the list of existing ones.

Parameters:

memberDeclarations - existing list of declarations

Returns:

new list of declarations or the same if no modifications required

isConstant

protected boolean isConstant(Expression expression)

Verifies if the expression is effectively constant. This method should be overridden in sub-classes.

Parameters:

expression - expression to test

Returns:

always returns false

isConstant

protected boolean isConstant(Iterable<? extends Expression> list)

Verifies if all the expressions in given list are effectively constant.

Parameters:

list - list of expressions to test

Returns:

true when all the expressions are known to be constant

findDeclaredExpression

protected @Nullable ParameterExpression findDeclaredExpression(Expression expression)

Finds if there exists ready for reuse declaration for given expression. This method should be overridden in sub-classes.

Parameters:

expression - input expression

Returns:

always returns null

hasField

protected boolean hasField(String name)

Verifies if the variable name is already in use. This method should be overridden in sub-classes.

Parameters:

name - name of the variable to test

Returns:

always returns false

goDeeper

protected ClassDeclarationFinder goDeeper()

Creates child visitor. It is used to traverse nested class declarations.

Returns:

new Visitor that is used to optimize class declarations