Interface ClassEntry

All Superinterfaces:: LoadableConstantEntry, PoolEntry

public sealed interface ClassEntry extends LoadableConstantEntry

Models a CONSTANT_Class_info structure, representing a reference type, in the constant pool of a class file.

The use of a ClassEntry is modeled by a ClassDesc that is not primitive. Conversions are through ConstantPoolBuilder.classEntry(ClassDesc) and asSymbol().

A ClassEntry is composite:

ClassEntry(Utf8Entry name)

where name represents:

The internal form of a binary name (JVMS 4.2.1), if and only if this ClassEntry represents a class or interface, such as java/lang/String for the String class.
A field descriptor string (JVMS 4.3.2) representing an array type, if and only if this ClassEntry represents an array type, such as [I for the int[] type, or [Ljava/lang/String; for the String[] type.

A field descriptor string for an array type can be distinguished by its leading '[' character.

API Note:

The internal form of a binary name, where all occurrences of . in the name are replaced by /, is informally known as an internal name. This concept also applies to package names in addition to class and interface names.

See Java Virtual Machine Specification:

4.4.1 The CONSTANT_Class_info Structure

Since:

See Also:

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

Method Summary

Modifier and Type	Method	Description
`String`	`asInternalName()`	Returns the represented reference type, as the internal form of a binary name or an array descriptor string.
`ClassDesc`	`asSymbol()`	Returns the represented reference type, as a symbolic descriptor.
`default ConstantDesc`	`constantValue()`	Returns a symbolic descriptor of this constant.
`boolean`	`matches(ClassDesc desc)`	Returns whether this entry describes the given reference type.
`Utf8Entry`	`name()`	Returns the `Utf8Entry` referred by this structure.

Methods declared in interface LoadableConstantEntry

typeKind

Methods declared in interface PoolEntry

constantPool, index, tag, width

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:

name

Utf8Entry name()

Returns the Utf8Entry referred by this structure. If the value of the UTF8 starts with a [, this represents an array type and the value is a descriptor string; otherwise, this represents a class or interface and the value is the internal form of a binary name.

Returns:

the Utf8Entry referred by this structure

See Also:

asInternalName

String asInternalName()

Returns the represented reference type, as the internal form of a binary name or an array descriptor string. This is a shortcut for name().stringValue().

Returns:: the represented reference type, as the internal form of a binary name or an array descriptor string

asSymbol

ClassDesc asSymbol()

Returns the represented reference type, as a symbolic descriptor. The returned descriptor is never primitive.

API Note:

If only symbol equivalence is desired, matches should be used. It requires reduced parsing and can improve class file reading performance.

Returns:

the represented reference type, as a symbolic descriptor

See Also:

matches

boolean matches(ClassDesc desc)

Returns whether this entry describes the given reference type. Returns false if desc is primitive.

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

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