Class.h File Reference

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Detailed Description

Interfaces to class functionality.

Classes
union	ConstPoolEntry
	The constant pool entry descriptor. More...
struct	ConstantPool
	The constant pool of a class and related operations. More...
struct	Class
	VM representation of Java class. More...
struct	Class.Class_Super
struct	Class.InnerClass
Defines
#define	CLASSFILE_MAGIC   0xCAFEBABE
#define	CLASSFILE_MAJOR_MIN   45
#define	CLASSFILE_MAJOR_MAX   50
#define	CLASSFILE_MINOR_MAX   0
Enumerations
enum	ConstPoolTags {   CONSTANT_Tags = 0, CONSTANT_Utf8 = 1, CONSTANT_Integer = 3, CONSTANT_Float = 4,   CONSTANT_Long = 5, CONSTANT_Double = 6, CONSTANT_Class = 7, CONSTANT_String = 8,   CONSTANT_Fieldref = 9, CONSTANT_Methodref = 10, CONSTANT_InterfaceMethodref = 11, CONSTANT_NameAndType = 12,   CONSTANT_Last = CONSTANT_NameAndType, CONSTANT_UnusedEntry = CONSTANT_Last + 1 }
	Types of constant pool entries. More...
enum	Class_State {   ST_Start, ST_LoadingAncestors, ST_Loaded, ST_BytecodesVerified,   ST_InstanceSizeComputed, ST_Prepared, ST_ConstraintsVerified, ST_Initializing,   ST_Initialized, ST_Error }
	The state of the Java class. More...
enum	AccessAndPropertiesFlags {   ACC_PUBLIC = 0x0001, ACC_PRIVATE = 0x0002, ACC_PROTECTED = 0x0004, ACC_STATIC = 0x0008,   ACC_FINAL = 0x0010, ACC_SUPER = 0x0020, ACC_SYNCHRONIZED = 0x0020, ACC_BRIDGE = 0x0040,   ACC_VOLATILE = 0x0040, ACC_VARARGS = 0x0080, ACC_TRANSIENT = 0x0080, ACC_NATIVE = 0x0100,   ACC_INTERFACE = 0x0200, ACC_ABSTRACT = 0x0400, ACC_STRICT = 0x0800, ACC_SYNTHETIC = 0x1000,   ACC_ANNOTATION = 0x2000, ACC_ENUM = 0x4000 }
	Access and properties flags for Class, Field and Method. More...
Functions
VMEXPORT String *	class_name_get_java_name (const String *class_name)
	Converts a class name from an internal (VM) form to the Java form.
ManagedObject *	struct_Class_to_java_lang_Class (Class *clss)
	Gets instance of java/lang/Class associated with this class.
jclass	struct_Class_to_jclass (Class *clss)
	Gets handle of java/lang/Class instance associated with this class.
Class *	jclass_to_struct_Class (jclass jc)
	Gets native class from the java/lang/Class handle.
Class *	jobject_to_struct_Class (jobject jobj)
	Gets native class for any given object handle.
jobject	struct_Class_to_java_lang_Class_Handle (Class *clss)
	Gets pointer to instance of java/lang/Class associated with the class.
Class *	java_lang_Class_to_struct_Class (ManagedObject *jlc)
	Gets native class from instance of java/lang/Class.
Field *	class_lookup_field_recursive (Class *clss, const char *name, const char *desc)
	Looks up field in class and its superclasses.
VMEXPORT Method *	class_lookup_method_recursive (Class *clss, const String *name, const String *desc)
	Looks up method in class and its superclasses.
Method *	class_lookup_method_recursive (Class *clss, const char *name, const char *desc)
	Looks up method in class and its superclasses.
Method *	class_lookup_method (Class *clss, const char *name, const char *desc)
	Looks up method in the given class only.
Method *	class_get_method_from_vt_offset (VTable *vt, unsigned offset)
	Gets method given its offset in the vtable.
Field *	class_resolve_nonstatic_field (Class *clss, unsigned cp_index)
	Resolves non-static field at the specified index in the constant pool of the class.
Class *	class_load_verify_prepare_by_loader_jni (Global_Env *env, const String *classname, ClassLoader *cl)
	Loads a class and performs the first two parts of the link process: verify and prepare.
Class *	class_load_verify_prepare_from_jni (Global_Env *env, const String *classname)
	Loads a class with bootstrap class loader and performs the first two parts of the link process: verify and prepare.
void	class_initialize_from_jni (Class *clss)
	Executes static initializer of class.
void	class_initialize_ex (Class *clss)
	Executes static initializer of class.
VMEXPORT void	class_initialize (Class *clss)
	Executes static initializer of class.
bool	class_register_methods (Class_Handle klass, const JNINativeMethod *methods, int num_methods)
	Registers a number of native methods to a given class.
bool	class_unregister_methods (Class_Handle klass)
	Unregisters a native methods off a given class.
Class *	resolve_class_new_env (Global_Env *env, Class *clss, unsigned cp_index, bool raise_exn)
Method *	resolve_special_method_env (Global_Env *env, Class_Handle curr_clss, unsigned index, bool raise_exn)
Method *	resolve_static_method_env (Global_Env *env, Class *clss, unsigned cp_index, bool raise_exn)
Method *	resolve_virtual_method_env (Global_Env *env, Class *clss, unsigned cp_index, bool raise_exn)
Method *	resolve_interface_method_env (Global_Env *env, Class *clss, unsigned cp_index, bool raise_exn)
Field *	resolve_static_field_env (Global_Env *env, Class *clss, unsigned cp_index, bool putfield, bool is_runtume)
Field *	resolve_nonstatic_field_env (Global_Env *env, Class *clss, unsigned cp_index, unsigned putfield, bool raise_exn)

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Define Documentation

#define CLASSFILE_MAGIC   0xCAFEBABE

#define CLASSFILE_MAJOR_MIN   45

#define CLASSFILE_MAJOR_MAX   50

#define CLASSFILE_MINOR_MAX   0

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Enumeration Type Documentation

enum ConstPoolTags

Types of constant pool entries.

These entry types are defined by a seperate byte array that the first constant pool entry points at.

Enumerator:

CONSTANT_Tags	pointer to the tags array.
CONSTANT_Utf8	The next 11 tag values are taken from The Java Virtual Machine Specification, Chapter 4, The Constant Pool section.
CONSTANT_Integer
CONSTANT_Float
CONSTANT_Long
CONSTANT_Double
CONSTANT_Class
CONSTANT_String
CONSTANT_Fieldref
CONSTANT_Methodref
CONSTANT_InterfaceMethodref
CONSTANT_NameAndType
CONSTANT_Last
CONSTANT_UnusedEntry	used to mark second entry of Long and Double

enum Class_State

The state of the Java class.

Enumerator:

ST_Start
ST_LoadingAncestors	the initial state
ST_Loaded	the loading super class and super interfaces
ST_BytecodesVerified	successfully loaded
ST_InstanceSizeComputed	bytecodes for methods verified for the class
ST_Prepared	preparing the class; instance size known
ST_ConstraintsVerified	successfully prepared
ST_Initializing	constraints verified for the class
ST_Initialized	initializing the class
ST_Error	bad class or the class initializer failed

enum AccessAndPropertiesFlags

Access and properties flags for Class, Field and Method.

Enumerator:

ACC_PUBLIC	Public access modifier. Valid for Class, Field, Method.
ACC_PRIVATE	Private access modifier. Valid for Field, Method.
ACC_PROTECTED	Protected access modifier. Valid for Field, Method.
ACC_STATIC	Static modifier. Valid for Field, Method.
ACC_FINAL	Final modifier. Valid for Class, Field, Method.
ACC_SUPER	Super modifier. Valid for Class.
ACC_SYNCHRONIZED	Synchronized modifier. Valid for Method.
ACC_BRIDGE	Bridge modifier. Valid for Method (since J2SE 5.0).
ACC_VOLATILE	Volatile modifier. Valid for Field.
ACC_VARARGS	Varargs modifier. Valid for Method (since J2SE 5.0).
ACC_TRANSIENT	Transient modifier. Valid for Field.
ACC_NATIVE	Native modifier. Valid for Method.
ACC_INTERFACE	Interface modifier. Valid for Class.
ACC_ABSTRACT	Abstract modifier. Valid for Class, Method.
ACC_STRICT	Strict modifier. Valid for Method.
ACC_SYNTHETIC	Synthetic modifier. Valid for Class, Field, Method (since J2SE 5.0).
ACC_ANNOTATION	Annotation modifier. Valid for Class (since J2SE 5.0).
ACC_ENUM	Enum modifier. Valid for Class, Field (since J2SE 5.0).

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Function Documentation

VMEXPORT String* class_name_get_java_name

(

const String *

class_name

)

Converts a class name from an internal (VM) form to the Java form.

Parameters:

[in]

class_name

- the class name in an internal form

Returns:

The class name in the Java form.

ManagedObject* struct_Class_to_java_lang_Class

(

Class *

clss

)

Gets instance of java/lang/Class associated with this class.

Parameters:

[in]

clss

- class to retrieve java/lang/Class instance for.

Returns:

Instance of java/lang/Class associated with class.

jclass struct_Class_to_jclass

(

Class *

clss

)

Gets handle of java/lang/Class instance associated with this class.

Parameters:

[in]

clss

- class to retrieve handle with java/lang/Class instance for.

Returns:

Handle with instance of java/lang/Class associated with class.

Note:

This function allocates local handle and stores reference to java/lang/Class into it.

Class* jclass_to_struct_Class

(

jclass

jc

)

Gets native class from the java/lang/Class handle.

Parameters:

[in]

jc

- handle to retrieve struct Class from.

Returns:

Class for the given handle.

Class* jobject_to_struct_Class

(

jobject

jobj

)

Gets native class for any given object handle.

Parameters:

[in]

jobj

- object to retrieve class for.

Returns:

Class for the given object handle.

jobject struct_Class_to_java_lang_Class_Handle

(

Class *

clss

)

Gets pointer to instance of java/lang/Class associated with the class.

Parameters:

[in]

clss

- class to retrieve pointer to instance of java/lang/Class for.

Returns:

Pointer to instance of java/lang/Class associated with the class.

Note:

This is NOT real handle, so, when using this function, make sure the returned value will never be passed to ANY user code including JVMTI agent callbacks.

Class* java_lang_Class_to_struct_Class

(

ManagedObject *

jlc

)

Gets native class from instance of java/lang/Class.

Parameters:

[in]

jlc

- instance of java/lang/Class to retrieve class from.

Returns:

Native class from instance of java/lang/Class.

Field* class_lookup_field_recursive	(	Class *	clss,
		const char *	name,
		const char *	desc
	)

Looks up field in class and its superclasses.

Parameters:

[in]	clss	- class to lookup field in.
[in]	name	- name of the field.
[in]	desc	- descriptor of the field.

Returns:

Requested field, if the field exists, NULL otherwise.

VMEXPORT Method* class_lookup_method_recursive	(	Class *	clss,
		const String *	name,
		const String *	desc
	)

Looks up method in class and its superclasses.

Parameters:

[in]	clss	- class to lookup method in.
[in]	name	- name of the method as VM String.
[in]	desc	- descriptor of the method as VM String.

Returns:

Requested method, if the method exists, NULL otherwise.

Note:

VMEXPORT specifier is solely for interpreter.

Method* class_lookup_method_recursive	(	Class *	clss,
		const char *	name,
		const char *	desc
	)

Looks up method in class and its superclasses.

Parameters:

[in]	clss	- class to lookup method in.
[in]	name	- name of the method.
[in]	desc	- descriptor of the method.

Returns:

Requested method, if the method exists, NULL otherwise.

Method* class_lookup_method	(	Class *	clss,
		const char *	name,
		const char *	desc
	)

Looks up method in the given class only.

Parameters:

[in]	clss	- class to lookup method in.
[in]	name	- name of the method.
[in]	desc	- descriptor of the method.

Returns:

Requested method, if the method exists, NULL otherwise.

Method* class_get_method_from_vt_offset	(	VTable *	vt,
		unsigned	offset
	)

Gets method given its offset in the vtable.

Parameters:

[in]	vt	- vtable containing method.
[in]	offset	- offset of the method in the vtable.

Returns:

Method at the specified offset.

Field* class_resolve_nonstatic_field	(	Class *	clss,
		unsigned	cp_index
	)

Resolves non-static field at the specified index in the constant pool of the class.

Parameters:

[in]	clss	- class to resolve field in.
[in]	cp_index	- index in the constant pool of the class.

Returns:

Resolved field, if resolution succeeded, NULL otherwise.

Class* class_load_verify_prepare_by_loader_jni	(	Global_Env *	env,
		const String *	classname,
		ClassLoader *	cl
	)

Loads a class and performs the first two parts of the link process: verify and prepare.

Parameters:

[in]	env	- VM environment.
[in]	classname	- name of a class to load.
[in]	cl	- class loader to load class with.

Returns:

Loaded class, if loading and linking succeeded, NULL otherwise.

Class* class_load_verify_prepare_from_jni	(	Global_Env *	env,
		const String *	classname
	)

Loads a class with bootstrap class loader and performs the first two parts of the link process: verify and prepare.

Parameters:

[in]	env	- VM environment.
[in]	classname	- name of a class to load.
[in]	cl	- class loader to load class with.

Returns:

Loaded class, if loading and linking succeeded, NULL otherwise.

Note:

The class is loaded .

void class_initialize_from_jni

(

Class *

clss

)

Executes static initializer of class.

Parameters:

[in]

clss

- class to initialize.

void class_initialize_ex

(

Class *

clss

)

Executes static initializer of class.

Parameters:

[in]

clss

- class to initialize.

VMEXPORT void class_initialize

(

Class *

clss

)

Executes static initializer of class.

Parameters:

[in]

clss

- class to initialize.

Note:

VMEXPORT specifier is solely for interpreter.

bool class_register_methods	(	Class_Handle	klass,
		const JNINativeMethod *	methods,
		int	num_methods
	)

Registers a number of native methods to a given class.

Parameters:

[in]	klass	- a specified class
[in]	methods	- an array of methods
[in]	num_methods	- a number of methods

Returns:

false, if methods resistration is successful; otherwise true.

Note:

Function raises NoSuchMethodError with the method name in exception message, if one of the methods in the JNINativeMethod* array is not present in a specified class.

bool class_unregister_methods

(

Class_Handle

klass

)

Unregisters a native methods off a given class.

Parameters:

[in]

klass

- specified class

Returns:

false, if methods unresistration is successful; otherwise true.

Class* resolve_class_new_env	(	Global_Env *	env,
		Class *	clss,
		unsigned	cp_index,
		bool	raise_exn
	)

Method* resolve_special_method_env	(	Global_Env *	env,
		Class_Handle	curr_clss,
		unsigned	index,
		bool	raise_exn
	)

Method* resolve_static_method_env	(	Global_Env *	env,
		Class *	clss,
		unsigned	cp_index,
		bool	raise_exn
	)

Method* resolve_virtual_method_env	(	Global_Env *	env,
		Class *	clss,
		unsigned	cp_index,
		bool	raise_exn
	)

Method* resolve_interface_method_env	(	Global_Env *	env,
		Class *	clss,
		unsigned	cp_index,
		bool	raise_exn
	)

Field* resolve_static_field_env	(	Global_Env *	env,
		Class *	clss,
		unsigned	cp_index,
		bool	putfield,
		bool	is_runtume
	)

Field* resolve_nonstatic_field_env	(	Global_Env *	env,
		Class *	clss,
		unsigned	cp_index,
		unsigned	putfield,
		bool	raise_exn
	)

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