Interface MethodTypeEntry

All Superinterfaces:: LoadableConstantEntry, PoolEntry

public sealed interface MethodTypeEntry extends LoadableConstantEntry

Models a CONSTANT_MethodType_info structure, or a symbolic reference to a method type, in the constant pool of a class file.

The use of a MethodTypeEntry is modeled by a MethodTypeDesc. Conversions are through ConstantPoolBuilder.methodTypeEntry(MethodTypeDesc) and asSymbol().

A method type entry is composite:

MethodTypeEntry(Utf8Entry descriptor)

where descriptor is a method descriptor string.

See Java Virtual Machine Specification:: 4.4.9 The CONSTANT_MethodType_info Structure
Since:: 24

Field Summary

Fields declared in interface PoolEntry

TAG_CLASS, TAG_DOUBLE, TAG_DYNAMIC, TAG_FIELDREF, TAG_FLOAT, TAG_INTEGER, TAG_INTERFACE_METHODREF, TAG_INVOKE_DYNAMIC, TAG_LONG, TAG_METHOD_HANDLE, TAG_METHOD_TYPE, TAG_METHODREF, TAG_MODULE, TAG_NAME_AND_TYPE, TAG_PACKAGE, TAG_STRING, TAG_UTF8

Modifier and Type	Field	Description
`static final int`	`TAG_CLASS`	The tag for `CONSTANT_Class` constant kind.
`static final int`	`TAG_DOUBLE`	The tag for `CONSTANT_Double` constant kind.
`static final int`	`TAG_DYNAMIC`	The tag for `CONSTANT_Dynamic` constant kind.
`static final int`	`TAG_FIELDREF`	The tag for `CONSTANT_Fieldref` constant kind.
`static final int`	`TAG_FLOAT`	The tag for `CONSTANT_Float` constant kind.
`static final int`	`TAG_INTEGER`	The tag for `CONSTANT_Integer` constant kind.
`static final int`	`TAG_INTERFACE_METHODREF`	The tag for `CONSTANT_InterfaceMethodref` constant kind.
`static final int`	`TAG_INVOKE_DYNAMIC`	The tag for `CONSTANT_InvokeDynamic` constant kind.
`static final int`	`TAG_LONG`	The tag for `CONSTANT_Long` constant kind.
`static final int`	`TAG_METHOD_HANDLE`	The tag for `CONSTANT_MethodHandle` constant kind.
`static final int`	`TAG_METHOD_TYPE`	The tag for `CONSTANT_MethodType` constant kind.
`static final int`	`TAG_METHODREF`	The tag for `CONSTANT_Methodref` constant kind.
`static final int`	`TAG_MODULE`	The tag for `CONSTANT_Module` constant kind.
`static final int`	`TAG_NAME_AND_TYPE`	The tag for `CONSTANT_NameAndType` constant kind.
`static final int`	`TAG_PACKAGE`	The tag for `CONSTANT_Package` constant kind.
`static final int`	`TAG_STRING`	The tag for `CONSTANT_String` constant kind.
`static final int`	`TAG_UTF8`	The tag for `CONSTANT_Utf8` constant kind.

Method Summary

Modifier and Type	Method	Description
`MethodTypeDesc`	`asSymbol()`	Returns a symbolic descriptor for the method type.
`default ConstantDesc`	`constantValue()`	Returns a symbolic descriptor of this constant.
`Utf8Entry`	`descriptor()`	Returns the method descriptor string.
`boolean`	`matches(MethodTypeDesc desc)`	Returns whether this entry describes the given method type.

Methods declared in interface LoadableConstantEntry

typeKind

Modifier and Type	Method	Description
`default TypeKind`	`typeKind()`	Returns the data type of this constant.

Methods declared in interface PoolEntry

constantPool, index, tag, width

Modifier and Type	Method	Description
`ConstantPool`	`constantPool()`	Returns the constant pool this entry is from.
`int`	`index()`	Returns the index within the constant pool corresponding to this entry.
`int`	`tag()`	Returns the constant pool tag that describes the type of this entry.
`int`	`width()`	Returns the number of constant pool slots this entry consumes.

Method Details

constantValue

default ConstantDesc constantValue()

Returns a symbolic descriptor of this constant.

This is equivalent to asSymbol().

Specified by:

constantValue in interface LoadableConstantEntry

Returns:

a symbolic descriptor of this constant

See Also:

descriptor

Utf8Entry descriptor()

Returns the method descriptor string.

Returns:: the method descriptor string

asSymbol

MethodTypeDesc asSymbol()

Returns a symbolic descriptor for the method type.

API Note:: If only symbol equivalence is desired, matches should be used. It requires reduced parsing and can improve class file reading performance.
Returns:: a symbolic descriptor for the method type

matches

boolean matches(MethodTypeDesc desc)

Returns whether this entry describes the given method type.

Parameters:: desc - the method type descriptor
Returns:: whether this entry describes the given method type
Since:: 25

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