Package org.objectweb.asm

Class Symbol

java.lang.Object

org.objectweb.asm.Symbol

Direct Known Subclasses:

SymbolTable.Entry

abstract class Symbol
extends Object

An entry of the constant pool, of the BootstrapMethods attribute, or of the (ASM specific) type table of a class.

See Also:

• JVMS 4.4
• JVMS 4.7.23

Field Summary

Fields

Modifier and Type	Field	Description
(package private) static final int	BOOTSTRAP_METHOD_TAG	The tag value of the BootstrapMethods attribute entries.
(package private) static final int	CONSTANT_CLASS_TAG	The tag value of CONSTANT_Class_info JVMS structures.
(package private) static final int	CONSTANT_DOUBLE_TAG	The tag value of CONSTANT_Double_info JVMS structures.
(package private) static final int	CONSTANT_DYNAMIC_TAG	The tag value of CONSTANT_Dynamic_info JVMS structures.
(package private) static final int	CONSTANT_FIELDREF_TAG	The tag value of CONSTANT_Fieldref_info JVMS structures.
(package private) static final int	CONSTANT_FLOAT_TAG	The tag value of CONSTANT_Float_info JVMS structures.
(package private) static final int	CONSTANT_INTEGER_TAG	The tag value of CONSTANT_Integer_info JVMS structures.
(package private) static final int	CONSTANT_INTERFACE_METHODREF_TAG	The tag value of CONSTANT_InterfaceMethodref_info JVMS structures.
(package private) static final int	CONSTANT_INVOKE_DYNAMIC_TAG	The tag value of CONSTANT_InvokeDynamic_info JVMS structures.
(package private) static final int	CONSTANT_LONG_TAG	The tag value of CONSTANT_Long_info JVMS structures.
(package private) static final int	CONSTANT_METHOD_HANDLE_TAG	The tag value of CONSTANT_MethodHandle_info JVMS structures.
(package private) static final int	CONSTANT_METHOD_TYPE_TAG	The tag value of CONSTANT_MethodType_info JVMS structures.
(package private) static final int	CONSTANT_METHODREF_TAG	The tag value of CONSTANT_Methodref_info JVMS structures.
(package private) static final int	CONSTANT_MODULE_TAG	The tag value of CONSTANT_Module_info JVMS structures.
(package private) static final int	CONSTANT_NAME_AND_TYPE_TAG	The tag value of CONSTANT_NameAndType_info JVMS structures.
(package private) static final int	CONSTANT_PACKAGE_TAG	The tag value of CONSTANT_Package_info JVMS structures.
(package private) static final int	CONSTANT_STRING_TAG	The tag value of CONSTANT_String_info JVMS structures.
(package private) static final int	CONSTANT_UTF8_TAG	The tag value of CONSTANT_Utf8_info JVMS structures.
(package private) final long	data	The numeric value of this symbol.
(package private) static final int	FORWARD_UNINITIALIZED_TYPE_TAG	The tag value of an uninitialized type entry in the type table of a class.
(package private) final int	index	The index of this symbol in the constant pool, in the BootstrapMethods attribute, or in the (ASM specific) type table of a class (depending on the tag value).
(package private) int	info	Additional information about this symbol, generally computed lazily.
(package private) static final int	MERGED_TYPE_TAG	The tag value of a merged type entry in the (ASM specific) type table of a class.
(package private) final String	name	The name of the class field or method corresponding to this symbol.
(package private) final String	owner	The internal name of the owner class of this symbol.
(package private) final int	tag	A tag indicating the type of this symbol.
(package private) static final int	TYPE_TAG	The tag value of a normal type entry in the (ASM specific) type table of a class.
(package private) static final int	UNINITIALIZED_TYPE_TAG	The tag value of an uninitialized type entry in the type table of a class.
(package private) final String	value	The string value of this symbol.

Constructor Summary

Constructors

Constructor	Description
Symbol(int index, int tag, String owner, String name, String value, long data)	Constructs a new Symbol.

Method Summary

Modifier and Type	Method	Description
(package private) int	getArgumentsAndReturnSizes()	Returns the result Type.getArgumentsAndReturnSizes() on value.

Methods inherited from class java.lang.Object

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

Field Details

CONSTANT_CLASS_TAG

static final int CONSTANT_CLASS_TAG

The tag value of CONSTANT_Class_info JVMS structures.

See Also:

• Constant Field Values

CONSTANT_FIELDREF_TAG

static final int CONSTANT_FIELDREF_TAG

The tag value of CONSTANT_Fieldref_info JVMS structures.

See Also:

• Constant Field Values

CONSTANT_METHODREF_TAG

static final int CONSTANT_METHODREF_TAG

The tag value of CONSTANT_Methodref_info JVMS structures.

See Also:

• Constant Field Values

CONSTANT_INTERFACE_METHODREF_TAG

static final int CONSTANT_INTERFACE_METHODREF_TAG

The tag value of CONSTANT_InterfaceMethodref_info JVMS structures.

See Also:

• Constant Field Values

CONSTANT_STRING_TAG

static final int CONSTANT_STRING_TAG

The tag value of CONSTANT_String_info JVMS structures.

See Also:

• Constant Field Values

CONSTANT_INTEGER_TAG

static final int CONSTANT_INTEGER_TAG

The tag value of CONSTANT_Integer_info JVMS structures.

See Also:

• Constant Field Values

CONSTANT_FLOAT_TAG

static final int CONSTANT_FLOAT_TAG

The tag value of CONSTANT_Float_info JVMS structures.

See Also:

• Constant Field Values

CONSTANT_LONG_TAG

static final int CONSTANT_LONG_TAG

The tag value of CONSTANT_Long_info JVMS structures.

See Also:

• Constant Field Values

CONSTANT_DOUBLE_TAG

static final int CONSTANT_DOUBLE_TAG

The tag value of CONSTANT_Double_info JVMS structures.

See Also:

• Constant Field Values

CONSTANT_NAME_AND_TYPE_TAG

static final int CONSTANT_NAME_AND_TYPE_TAG

The tag value of CONSTANT_NameAndType_info JVMS structures.

See Also:

• Constant Field Values

CONSTANT_UTF8_TAG

static final int CONSTANT_UTF8_TAG

The tag value of CONSTANT_Utf8_info JVMS structures.

See Also:

• Constant Field Values

CONSTANT_METHOD_HANDLE_TAG

static final int CONSTANT_METHOD_HANDLE_TAG

The tag value of CONSTANT_MethodHandle_info JVMS structures.

See Also:

• Constant Field Values

CONSTANT_METHOD_TYPE_TAG

static final int CONSTANT_METHOD_TYPE_TAG

The tag value of CONSTANT_MethodType_info JVMS structures.

See Also:

• Constant Field Values

CONSTANT_DYNAMIC_TAG

static final int CONSTANT_DYNAMIC_TAG

The tag value of CONSTANT_Dynamic_info JVMS structures.

See Also:

• Constant Field Values

CONSTANT_INVOKE_DYNAMIC_TAG

static final int CONSTANT_INVOKE_DYNAMIC_TAG

The tag value of CONSTANT_InvokeDynamic_info JVMS structures.

See Also:

• Constant Field Values

CONSTANT_MODULE_TAG

static final int CONSTANT_MODULE_TAG

The tag value of CONSTANT_Module_info JVMS structures.

See Also:

• Constant Field Values

CONSTANT_PACKAGE_TAG

static final int CONSTANT_PACKAGE_TAG

The tag value of CONSTANT_Package_info JVMS structures.

See Also:

• Constant Field Values

BOOTSTRAP_METHOD_TAG

static final int BOOTSTRAP_METHOD_TAG

The tag value of the BootstrapMethods attribute entries.

See Also:

• Constant Field Values

TYPE_TAG

static final int TYPE_TAG

The tag value of a normal type entry in the (ASM specific) type table of a class.

See Also:

• Constant Field Values

UNINITIALIZED_TYPE_TAG

static final int UNINITIALIZED_TYPE_TAG

The tag value of an uninitialized type entry in the type table of a class. This type is used for the normal case where the NEW instruction is before the <init> constructor call (in bytecode offset order), i.e. when the label of the NEW instruction is resolved when the constructor call is visited. If the NEW instruction is after the constructor call, use the FORWARD_UNINITIALIZED_TYPE_TAG tag value instead.

See Also:

• Constant Field Values

FORWARD_UNINITIALIZED_TYPE_TAG

static final int FORWARD_UNINITIALIZED_TYPE_TAG

The tag value of an uninitialized type entry in the type table of a class. This type is used for the unusual case where the NEW instruction is after the <init> constructor call (in bytecode offset order), i.e. when the label of the NEW instruction is not resolved when the constructor call is visited. If the NEW instruction is before the constructor call, use the UNINITIALIZED_TYPE_TAG tag value instead.

See Also:

• Constant Field Values

MERGED_TYPE_TAG

static final int MERGED_TYPE_TAG

The tag value of a merged type entry in the (ASM specific) type table of a class.

See Also:

• Constant Field Values

index

final int index

The index of this symbol in the constant pool, in the BootstrapMethods attribute, or in the (ASM specific) type table of a class (depending on the tag value).

tag

final int tag

A tag indicating the type of this symbol. Must be one of the static tag values defined in this class.

owner

final String owner

The internal name of the owner class of this symbol. Only used for CONSTANT_FIELDREF_TAG, CONSTANT_METHODREF_TAG, CONSTANT_INTERFACE_METHODREF_TAG, and CONSTANT_METHOD_HANDLE_TAG symbols.

name

final String name

The name of the class field or method corresponding to this symbol. Only used for CONSTANT_FIELDREF_TAG, CONSTANT_METHODREF_TAG, CONSTANT_INTERFACE_METHODREF_TAG, CONSTANT_NAME_AND_TYPE_TAG, CONSTANT_METHOD_HANDLE_TAG, CONSTANT_DYNAMIC_TAG and CONSTANT_INVOKE_DYNAMIC_TAG symbols.

value

final String value

The string value of this symbol. This is:

• a field or method descriptor for CONSTANT_FIELDREF_TAG, CONSTANT_METHODREF_TAG, CONSTANT_INTERFACE_METHODREF_TAG, CONSTANT_NAME_AND_TYPE_TAG, CONSTANT_METHOD_HANDLE_TAG, CONSTANT_METHOD_TYPE_TAG, CONSTANT_DYNAMIC_TAG and CONSTANT_INVOKE_DYNAMIC_TAG symbols,
• an arbitrary string for CONSTANT_UTF8_TAG and CONSTANT_STRING_TAG symbols,
• an internal class name for CONSTANT_CLASS_TAG, TYPE_TAG, UNINITIALIZED_TYPE_TAG and FORWARD_UNINITIALIZED_TYPE_TAG symbols,
• null for the other types of symbol.

data

final long data

The numeric value of this symbol. This is:

• the symbol's value for CONSTANT_INTEGER_TAG,CONSTANT_FLOAT_TAG, CONSTANT_LONG_TAG, CONSTANT_DOUBLE_TAG,
• the CONSTANT_MethodHandle_info reference_kind field value for CONSTANT_METHOD_HANDLE_TAG symbols,
• the CONSTANT_InvokeDynamic_info bootstrap_method_attr_index field value for CONSTANT_INVOKE_DYNAMIC_TAG symbols,
• the offset of a bootstrap method in the BootstrapMethods boostrap_methods array, for CONSTANT_DYNAMIC_TAG or BOOTSTRAP_METHOD_TAG symbols,
• the bytecode offset of the NEW instruction that created an Frame.ITEM_UNINITIALIZED type for UNINITIALIZED_TYPE_TAG symbols,
• the index of the Label (in the SymbolTable.labelTable table) of the NEW instruction that created an Frame.ITEM_UNINITIALIZED type for FORWARD_UNINITIALIZED_TYPE_TAG symbols,
• the indices (in the class' type table) of two TYPE_TAG source types for MERGED_TYPE_TAG symbols,
• 0 for the other types of symbol.

info

int info

Additional information about this symbol, generally computed lazily. Warning: the value of this field is ignored when comparing Symbol instances (to avoid duplicate entries in a SymbolTable). Therefore, this field should only contain data that can be computed from the other fields of this class. It contains:

• the Type.getArgumentsAndReturnSizes() of the symbol's method descriptor for CONSTANT_METHODREF_TAG, CONSTANT_INTERFACE_METHODREF_TAG and CONSTANT_INVOKE_DYNAMIC_TAG symbols,
• the index in the InnerClasses_attribute 'classes' array (plus one) corresponding to this class, for CONSTANT_CLASS_TAG symbols,
• the index (in the class' type table) of the merged type of the two source types for MERGED_TYPE_TAG symbols,
• 0 for the other types of symbol, or if this field has not been computed yet.

Constructor Details

Symbol

Symbol(int index,
 int tag,
 String owner,
 String name,
 String value,
 long data)

Constructs a new Symbol. This constructor can't be used directly because the Symbol class is abstract. Instead, use the factory methods of the SymbolTable class.

Parameters:

index - the symbol index in the constant pool, in the BootstrapMethods attribute, or in the (ASM specific) type table of a class (depending on 'tag').

tag - the symbol type. Must be one of the static tag values defined in this class.

owner - The internal name of the symbol's owner class. Maybe null.

name - The name of the symbol's corresponding class field or method. Maybe null.

value - The string value of this symbol. Maybe null.

data - The numeric value of this symbol.

Method Details

getArgumentsAndReturnSizes

int getArgumentsAndReturnSizes()

Returns the result Type.getArgumentsAndReturnSizes() on value.

Returns:

the result Type.getArgumentsAndReturnSizes() on value (memoized in info for efficiency). This should only be used for CONSTANT_METHODREF_TAG, CONSTANT_INTERFACE_METHODREF_TAG and CONSTANT_INVOKE_DYNAMIC_TAG symbols.