Package org.apache.calcite.linq4j.tree

Class Types

java.lang.Object

org.apache.calcite.linq4j.tree.Types

public abstract class Types
extends Object

Utilities for converting between Expression, Type and Class.

See Also:

Primitive

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	Types.ArrayType	Array type.
static class	Types.MapType	Map type.
(package private) static class	Types.ParameterizedTypeImpl	Implementation of ParameterizedType.
static interface	Types.RecordField	Field that belongs to a record.
static interface	Types.RecordType	Base class for record-like types that do not mapped to (currently loaded) Java Class objects.

Constructor Summary

Constructors

Modifier	Constructor	Description
private	Types()

Method Summary

Modifier and Type	Method	Description
(package private) static boolean	allAssignable(boolean varArgs, Class[] parameterTypes, Class[] argumentTypes)
(package private) static Class	arrayClass(Type type)
(package private) static Type	arrayType(Type type)
(package private) static Type	arrayType(Type type, int dimension)
private static boolean	assignableFrom(Class parameter, Class argument)	Returns whether a parameter is assignable from an argument by virtue of (a) sub-classing (e.g.
static Type	box(Type type)
(package private) static String	boxClassName(Type type)	Boxes a type, if it is primitive, and returns the type name.
static Expression	castIfNecessary(Type returnType, Expression expression)	Wraps an expression in a cast if it is not already of the desired type, or cannot be implicitly converted to it.
(package private) static String	className(Type type)
static void	discard(Object o)
static PseudoField	field(Field field)
(package private) static Type	gcd(Type... types)	Returns the most restrictive type that is assignable from all given types.
static Type	getComponentType(Type type)	Returns the component type of an array.
(package private) static Type	getComponentTypeN(Type type)
static Type	getElementType(Type type)	Returns the element type of a Collection, Iterable (including Queryable and Enumerable), Iterator, Enumerator, or an array.
(package private) static Field	getField(String fieldName, Class clazz)
(package private) static PseudoField	getField(String fieldName, Type type)
private static Types.RecordField	getRecordField(String fieldName, Types.RecordType type)
private static Types.RecordField	getSystemField(String fieldName, Class clazz)
static boolean	isArray(Type type)
static boolean	isAssignableFrom(Type type0, Type type)
static Constructor	lookupConstructor(Type type, Class... argumentTypes)	Finds a constructor of a given class that accepts a given set of arguments.
static Field	lookupField(Type type, String name)
static Method	lookupMethod(Class clazz, String methodName, Class... argumentTypes)	Finds a method of a given name that accepts a given set of arguments.
static Field	nthField(int ordinal, Class clazz)
static PseudoField	nthField(int ordinal, Type clazz)
static Type	of(Type type, Type... typeArguments)	Creates a type with generic parameters.
static Type	stripGenerics(Type type)
static Class	toClass(Type type)
(package private) static Class[]	toClassArray(Iterable<? extends Expression> arguments)
(package private) static Class[]	toClassArray(Collection<Type> types)
private static <T> List<T>	toList(T[] ts)	Returns a list backed by a copy of an array.
static Type	unbox(Type type)

Methods inherited from class java.lang.Object

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

Constructor Detail

Types

private Types()

Method Detail

of

public static Type of(Type type,
                      Type... typeArguments)

Creates a type with generic parameters.

getElementType

public static Type getElementType(Type type)

Returns the element type of a Collection, Iterable (including Queryable and Enumerable), Iterator, Enumerator, or an array.

Returns null if the type is not one of these.

toList

private static <T> List<T> toList(T[] ts)

Returns a list backed by a copy of an array. The contents of the list will not change even if the contents of the array are subsequently modified.

getField

static Field getField(String fieldName,
                      Class clazz)

getField

static PseudoField getField(String fieldName,
                            Type type)

getRecordField

private static Types.RecordField getRecordField(String fieldName,
                                                Types.RecordType type)

getSystemField

private static Types.RecordField getSystemField(String fieldName,
                                                Class clazz)

toClass

public static Class toClass(Type type)

toClassArray

static Class[] toClassArray(Collection<Type> types)

toClassArray

static Class[] toClassArray(Iterable<? extends Expression> arguments)

getComponentType

public static Type getComponentType(Type type)

Returns the component type of an array.

getComponentTypeN

static Type getComponentTypeN(Type type)

boxClassName

static String boxClassName(Type type)

Boxes a type, if it is primitive, and returns the type name. The type is abbreviated if it is in the "java.lang" package.

For example, boxClassName(int) returns "Integer"; boxClassName(List<String>) returns "List<String>"

Parameters:

type - Type

Returns:

Class name

box

public static Type box(Type type)

unbox

public static Type unbox(Type type)

className

static String className(Type type)

isAssignableFrom

public static boolean isAssignableFrom(Type type0,
                                       Type type)

isArray

public static boolean isArray(Type type)

nthField

public static Field nthField(int ordinal,
                             Class clazz)

nthField

public static PseudoField nthField(int ordinal,
                                   Type clazz)

allAssignable

static boolean allAssignable(boolean varArgs,
                             Class[] parameterTypes,
                             Class[] argumentTypes)

assignableFrom

private static boolean assignableFrom(Class parameter,
                                      Class argument)

Returns whether a parameter is assignable from an argument by virtue of (a) sub-classing (e.g. Writer is assignable from PrintWriter) and (b) up-casting (e.g. int is assignable from short).

Parameters:

parameter - Parameter type

argument - Argument type

Returns:

Whether parameter can be assigned from argument

lookupMethod

public static Method lookupMethod(Class clazz,
                                  String methodName,
                                  Class... argumentTypes)

Finds a method of a given name that accepts a given set of arguments. Includes in its search inherited methods and methods with wider argument types.

Parameters:

clazz - Class against which method is invoked

methodName - Name of method

argumentTypes - Types of arguments

Returns:

A method with the given name that matches the arguments given

Throws:

RuntimeException - if method not found

lookupConstructor

public static Constructor lookupConstructor(Type type,
                                            Class... argumentTypes)

Finds a constructor of a given class that accepts a given set of arguments. Includes in its search methods with wider argument types.

Parameters:

type - Class against which method is invoked

argumentTypes - Types of arguments

Returns:

A method with the given name that matches the arguments given

Throws:

RuntimeException - if method not found

lookupField

public static Field lookupField(Type type,
                                String name)

discard

public static void discard(Object o)

gcd

static Type gcd(Type... types)

Returns the most restrictive type that is assignable from all given types.

castIfNecessary

public static Expression castIfNecessary(Type returnType,
                                         Expression expression)

Wraps an expression in a cast if it is not already of the desired type, or cannot be implicitly converted to it.

Parameters:

returnType - Desired type

expression - Expression

Returns:

Expression of desired type

field

public static PseudoField field(Field field)

arrayClass

static Class arrayClass(Type type)

arrayType

static Type arrayType(Type type,
                      int dimension)

arrayType

static Type arrayType(Type type)

stripGenerics

public static Type stripGenerics(Type type)