Package dev.cel.common.ast

Class CelExpr

java.lang.Object

dev.cel.common.ast.CelExpr

@Internal
@Immutable
public abstract class CelExpr
extends java.lang.Object

An abstract representation of a common expression.

This is the native type equivalent of Expr message in syntax.proto.

Expressions are abstractly represented as a collection of identifiers, select statements, function calls, literals, and comprehensions. All operators with the exception of the '.' operator are modelled as function calls. This makes it easy to represent new operators into the existing AST.

All references within expressions must resolve to a [Decl][] provided at type-check for an expression to be valid. A reference may either be a bare identifier `name` or a qualified identifier `google.api.name`. References may either refer to a value or a function declaration.

For example, the expression `google.api.name.startsWith('expr')` references the declaration `google.api.name` within a [Expr.Select][] expression, and the function declaration `startsWith`.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	CelExpr.Builder	Builder for CelExpr.
static class	CelExpr.CelCall	A call expression, including calls to predefined functions and operators.
static class	CelExpr.CelComprehension	A comprehension expression applied to a list or map.
static class	CelExpr.CelCreateList	A list creation expression.
static class	CelExpr.CelCreateMap	A map creation expression.
static class	CelExpr.CelCreateStruct	A message creation expression.
static class	CelExpr.CelIdent	An identifier expression.
static class	CelExpr.CelNotSet	An unset expression.
static class	CelExpr.CelSelect	A field selection expression.
static class	CelExpr.ExprKind	Denotes the kind of the expression.

Constructor Summary

Constructors

Constructor	Description
CelExpr()

Method Summary

Modifier and Type	Method	Description
CelExpr.CelCall	call()	Gets the underlying call expression.
CelExpr.CelCall	callOrDefault()	Gets the underlying call expression or a default instance of one if expression is not CelExpr.ExprKind.Kind.CALL.
CelExpr.CelComprehension	comprehension()	Gets the underlying comprehension expression.
CelExpr.CelComprehension	comprehensionOrDefault()	Gets the underlying comprehension expression or a default instance of one if expression is not CelExpr.ExprKind.Kind.COMPREHENSION.
CelConstant	constant()	Gets the underlying constant expression.
CelConstant	constantOrDefault()	Gets the underlying constant expression or a default instance of one if expression is not CelExpr.ExprKind.Kind.CONSTANT.
CelExpr.CelCreateList	createList()	Gets the underlying createList expression.
CelExpr.CelCreateList	createListOrDefault()	Gets the underlying createList expression or a default instance of one if expression is not CelExpr.ExprKind.Kind.CREATE_LIST.
CelExpr.CelCreateMap	createMap()	Gets the underlying createMap expression.
CelExpr.CelCreateMap	createMapOrDefault()	Gets the underlying createMap expression or a default instance of one if expression is not CelExpr.ExprKind.Kind.CREATE_MAP.
CelExpr.CelCreateStruct	createStruct()	Gets the underlying createStruct expression.
CelExpr.CelCreateStruct	createStructOrDefault()	Gets the underlying createStruct expression or a default instance of one if expression is not CelExpr.ExprKind.Kind.CREATE_STRUCT.
abstract CelExpr.ExprKind	exprKind()	Represents the variant of the expression.
abstract long	id()	Required.
CelExpr.CelIdent	ident()	Gets the underlying identifier expression.
CelExpr.CelIdent	identOrDefault()	Gets the underlying identifier expression or a default instance of one if expression is not CelExpr.ExprKind.Kind.IDENT.
static CelExpr.Builder	newBuilder()
static CelExpr	ofCallExpr(long id, java.util.Optional<CelExpr> targetExpr, java.lang.String function, com.google.common.collect.ImmutableList<CelExpr> arguments)
static CelExpr	ofComprehension(long id, java.lang.String iterVar, CelExpr iterRange, java.lang.String accuVar, CelExpr accuInit, CelExpr loopCondition, CelExpr loopStep, CelExpr result)
static CelExpr	ofConstantExpr(long id, CelConstant celConstant)
static CelExpr	ofCreateListExpr(long id, com.google.common.collect.ImmutableList<CelExpr> elements, com.google.common.collect.ImmutableList<java.lang.Integer> optionalIndices)
static CelExpr.CelCreateMap.Entry	ofCreateMapEntryExpr(long id, CelExpr mapKey, CelExpr value, boolean isOptionalEntry)
static CelExpr	ofCreateMapExpr(long id, com.google.common.collect.ImmutableList<CelExpr.CelCreateMap.Entry> entries)
static CelExpr.CelCreateStruct.Entry	ofCreateStructEntryExpr(long id, java.lang.String fieldKey, CelExpr value, boolean isOptionalEntry)
static CelExpr	ofCreateStructExpr(long id, java.lang.String messageName, com.google.common.collect.ImmutableList<CelExpr.CelCreateStruct.Entry> entries)
static CelExpr	ofIdentExpr(long id, java.lang.String identName)
static CelExpr	ofNotSet(long id)
static CelExpr	ofSelectExpr(long id, CelExpr operandExpr, java.lang.String field, boolean isTestOnly)
CelExpr.CelSelect	select()	Gets the underlying select expression.
CelExpr.CelSelect	selectOrDefault()	Gets the underlying select expression or a default instance of one if expression is not CelExpr.ExprKind.Kind.SELECT.
abstract CelExpr.Builder	toBuilder()
java.lang.String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

CelExpr

public CelExpr()

Method Detail

id

public abstract long id()

Required. An id assigned to this node by the parser which is unique in a given expression tree. This is used to associate type information and other attributes to a node in the parse tree.

exprKind

public abstract CelExpr.ExprKind exprKind()

Represents the variant of the expression.

constant

public CelConstant constant()

Gets the underlying constant expression.

Throws:

java.lang.UnsupportedOperationException - if expression is not CelExpr.ExprKind.Kind.CONSTANT.

ident

public CelExpr.CelIdent ident()

Gets the underlying identifier expression.

Throws:

java.lang.UnsupportedOperationException - if expression is not CelExpr.ExprKind.Kind.IDENT.

select

public CelExpr.CelSelect select()

Gets the underlying select expression.

Throws:

java.lang.UnsupportedOperationException - if expression is not CelExpr.ExprKind.Kind.SELECT.

call

public CelExpr.CelCall call()

Gets the underlying call expression.

Throws:

java.lang.UnsupportedOperationException - if expression is not CelExpr.ExprKind.Kind.CALL.

createList

public CelExpr.CelCreateList createList()

Gets the underlying createList expression.

Throws:

java.lang.UnsupportedOperationException - if expression is not CelExpr.ExprKind.Kind.CREATE_LIST.

createStruct

public CelExpr.CelCreateStruct createStruct()

Gets the underlying createStruct expression.

Throws:

java.lang.UnsupportedOperationException - if expression is not CelExpr.ExprKind.Kind.CREATE_STRUCT.

createMap

public CelExpr.CelCreateMap createMap()

Gets the underlying createMap expression.

Throws:

java.lang.UnsupportedOperationException - if expression is not CelExpr.ExprKind.createMap().

comprehension

public CelExpr.CelComprehension comprehension()

Gets the underlying comprehension expression.

Throws:

java.lang.UnsupportedOperationException - if expression is not CelExpr.ExprKind.Kind.COMPREHENSION.

constantOrDefault

public CelConstant constantOrDefault()

Gets the underlying constant expression or a default instance of one if expression is not CelExpr.ExprKind.Kind.CONSTANT.

identOrDefault

public CelExpr.CelIdent identOrDefault()

Gets the underlying identifier expression or a default instance of one if expression is not CelExpr.ExprKind.Kind.IDENT.

selectOrDefault

public CelExpr.CelSelect selectOrDefault()

Gets the underlying select expression or a default instance of one if expression is not CelExpr.ExprKind.Kind.SELECT.

callOrDefault

public CelExpr.CelCall callOrDefault()

Gets the underlying call expression or a default instance of one if expression is not CelExpr.ExprKind.Kind.CALL.

createListOrDefault

public CelExpr.CelCreateList createListOrDefault()

Gets the underlying createList expression or a default instance of one if expression is not CelExpr.ExprKind.Kind.CREATE_LIST.

createStructOrDefault

public CelExpr.CelCreateStruct createStructOrDefault()

Gets the underlying createStruct expression or a default instance of one if expression is not CelExpr.ExprKind.Kind.CREATE_STRUCT.

createMapOrDefault

public CelExpr.CelCreateMap createMapOrDefault()

Gets the underlying createMap expression or a default instance of one if expression is not CelExpr.ExprKind.Kind.CREATE_MAP.

comprehensionOrDefault

public CelExpr.CelComprehension comprehensionOrDefault()

Gets the underlying comprehension expression or a default instance of one if expression is not CelExpr.ExprKind.Kind.COMPREHENSION.

toBuilder

public abstract CelExpr.Builder toBuilder()

newBuilder

public static CelExpr.Builder newBuilder()

ofNotSet

public static CelExpr ofNotSet(long id)

ofConstantExpr

public static CelExpr ofConstantExpr(long id,
                                     CelConstant celConstant)

ofIdentExpr

public static CelExpr ofIdentExpr(long id,
                                  java.lang.String identName)

ofSelectExpr

public static CelExpr ofSelectExpr(long id,
                                   CelExpr operandExpr,
                                   java.lang.String field,
                                   boolean isTestOnly)

ofCallExpr

public static CelExpr ofCallExpr(long id,
                                 java.util.Optional<CelExpr> targetExpr,
                                 java.lang.String function,
                                 com.google.common.collect.ImmutableList<CelExpr> arguments)

ofCreateListExpr

public static CelExpr ofCreateListExpr(long id,
                                       com.google.common.collect.ImmutableList<CelExpr> elements,
                                       com.google.common.collect.ImmutableList<java.lang.Integer> optionalIndices)

ofCreateStructExpr

public static CelExpr ofCreateStructExpr(long id,
                                         java.lang.String messageName,
                                         com.google.common.collect.ImmutableList<CelExpr.CelCreateStruct.Entry> entries)

ofCreateMapExpr

public static CelExpr ofCreateMapExpr(long id,
                                      com.google.common.collect.ImmutableList<CelExpr.CelCreateMap.Entry> entries)

ofCreateStructEntryExpr

public static CelExpr.CelCreateStruct.Entry ofCreateStructEntryExpr(long id,
                                                                    java.lang.String fieldKey,
                                                                    CelExpr value,
                                                                    boolean isOptionalEntry)

ofCreateMapEntryExpr

public static CelExpr.CelCreateMap.Entry ofCreateMapEntryExpr(long id,
                                                              CelExpr mapKey,
                                                              CelExpr value,
                                                              boolean isOptionalEntry)

ofComprehension

public static CelExpr ofComprehension(long id,
                                      java.lang.String iterVar,
                                      CelExpr iterRange,
                                      java.lang.String accuVar,
                                      CelExpr accuInit,
                                      CelExpr loopCondition,
                                      CelExpr loopStep,
                                      CelExpr result)

toString

public final java.lang.String toString()

Overrides:

toString in class java.lang.Object