net.lenni0451.reflect

Class Objects

java.lang.Object

net.lenni0451.reflect.Objects

public class Objects
extends java.lang.Object

This class contains some methods to do unsafe operations.

Field Summary

Fields

Modifier and Type	Field and Description
static int	ADDRESS_SIZE
static long	ARRAY_BASE_OFFSET
static int	ARRAY_HEADER_SIZE
static int	ARRAY_INDEX_SCALE
static long	COMPRESSED_OOP_BASE
static int	COMPRESSED_OOP_SHIFT
static boolean	COMPRESSED_OOPS
static long	KLASS_OFFSET
static int	OBJECT_ALIGNMENT
static int	OBJECT_HEADER_SIZE
static int	OOP_SIZE

Constructor Summary

Constructors

Constructor and Description
Objects()

Method Summary

Modifier and Type	Method and Description
static <T> T	allocate(java.lang.Class<T> clazz) Allocate an instance of the given class.
static <T> T	cast(java.lang.Object o, java.lang.Class<T> target) Cast the given object to the given class.
static <T> T	cast(java.lang.Object o, long klass) Cast the given object to the given class pointer.
static <T> T	cast(java.lang.Object o, java.lang.Object target) Cast the given object to the given object.
static void	copyMemory(java.lang.Object from, long fromOffset, java.lang.Object to, long toOffset, long size) Copy the memory from one object to another with the given offsets.
static void	copyMemory(java.lang.Object from, java.lang.Object to, long size) Copy the memory from one object to another.
static <T> T	fromAddress(long jvmAddress) Deprecated.
static <T> T	fromJVMAddress(long jvmAddress) Get the object at the given jvm memory address.
static long	getKlass(java.lang.Class<?> clazz) Get the class pointer of the given class.
static long	getKlass(java.lang.Object o) Get the class pointer of the given object.
static long	toAddress(java.lang.Object o) Deprecated.
static long	toJVMAddress(long nativeAddress) Convert a native address to a jvm address.
static long	toJVMAddress(java.lang.Object o) Get the jvm memory address of an object.
static long	toNativeAddress(long jvmAddress) Convert a jvm address to a native address.
static long	toNativeAddress(java.lang.Object o) Get the native address of an object.

Methods inherited from class java.lang.Object

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

Field Detail

ARRAY_BASE_OFFSET

public static final long ARRAY_BASE_OFFSET

ARRAY_INDEX_SCALE

public static final int ARRAY_INDEX_SCALE

ADDRESS_SIZE

public static final int ADDRESS_SIZE

OOP_SIZE

public static final int OOP_SIZE

OBJECT_HEADER_SIZE

public static final int OBJECT_HEADER_SIZE

ARRAY_HEADER_SIZE

public static final int ARRAY_HEADER_SIZE

OBJECT_ALIGNMENT

public static final int OBJECT_ALIGNMENT

COMPRESSED_OOPS

public static final boolean COMPRESSED_OOPS

COMPRESSED_OOP_SHIFT

public static final int COMPRESSED_OOP_SHIFT

COMPRESSED_OOP_BASE

public static final long COMPRESSED_OOP_BASE

KLASS_OFFSET

public static final long KLASS_OFFSET

Constructor Detail

Objects

public Objects()

Method Detail

toAddress

@Deprecated
public static long toAddress(java.lang.Object o)

Deprecated.

Use toJVMAddress(Object).

toJVMAddress

public static long toJVMAddress(java.lang.Object o)

Get the jvm memory address of an object.

Parameters:

o - The object

Returns:

The jvm memory address

Throws:

InvalidOOPSizeException - If the OOP size is not 4 or 8

toJVMAddress

public static long toJVMAddress(long nativeAddress)

Convert a native address to a jvm address.

Parameters:

nativeAddress - The native address

Returns:

The jvm address

toNativeAddress

public static long toNativeAddress(java.lang.Object o)

Get the native address of an object.

Parameters:

o - The object

Returns:

The native address

Throws:

java.lang.IllegalStateException - If the OOP size is not 4 or 8

toNativeAddress

public static long toNativeAddress(long jvmAddress)

Convert a jvm address to a native address.

Parameters:

jvmAddress - The jvm address

Returns:

The native address

fromAddress

@Deprecated
public static <T> T fromAddress(long jvmAddress)

Deprecated.

Use fromJVMAddress(long).

fromJVMAddress

public static <T> T fromJVMAddress(long jvmAddress)

Get the object at the given jvm memory address.

Type Parameters:

T - The type of the object

Parameters:

jvmAddress - The jvm memory address

Returns:

The object

Throws:

InvalidOOPSizeException - If the OOP size is not 4 or 8

copyMemory

public static void copyMemory(java.lang.Object from,
                              java.lang.Object to,
                              long size)

Copy the memory from one object to another.

Parameters:

from - The source object

to - The target object

size - The size of the memory to copy

copyMemory

public static void copyMemory(java.lang.Object from,
                              long fromOffset,
                              java.lang.Object to,
                              long toOffset,
                              long size)

Copy the memory from one object to another with the given offsets.

Parameters:

from - The source object

fromOffset - The offset in the source object

to - The target object

toOffset - The offset in the target object

size - The size of the memory to copy

getKlass

public static long getKlass(java.lang.Class<?> clazz)

Get the class pointer of the given class.

Parameters:

clazz - The class

Returns:

The class pointer

Throws:

java.lang.InstantiationException - If the class can not be allocated

getKlass

public static long getKlass(java.lang.Object o)

Get the class pointer of the given object.

Parameters:

o - The object

Returns:

The class pointer

Throws:

InvalidOOPSizeException - If the OOP size is not 4 or 8

cast

public static <T> T cast(java.lang.Object o,
                         java.lang.Class<T> target)

Cast the given object to the given class.

Type Parameters:

T - The type of the object

Parameters:

o - The object

target - The target class

Returns:

The casted object

cast

public static <T> T cast(java.lang.Object o,
                         java.lang.Object target)

Cast the given object to the given object.

Type Parameters:

T - The type of the object

Parameters:

o - The object

target - The target object

Returns:

The casted object

cast

public static <T> T cast(java.lang.Object o,
                         long klass)

Cast the given object to the given class pointer.

Type Parameters:

T - The type of the object

Parameters:

o - The object

klass - The class pointer

Returns:

The casted object

Throws:

java.lang.ClassCastException - If the object can not be casted

java.lang.UnsupportedOperationException - If the JVM is OpenJ9

allocate

public static <T> T allocate(java.lang.Class<T> clazz)

Allocate an instance of the given class.

Type Parameters:

T - The type of the instance

Parameters:

clazz - The class

Returns:

The allocated instance

Throws:

java.lang.InstantiationException - If the class can not be allocated

java.lang.ClassCastException - If the object does not match the given class