程序包 cn.taketoday.util

类 DefineClassHelper

java.lang.Object

cn.taketoday.util.DefineClassHelper

public class DefineClassHelper
extends Object

Helper class for invoking ClassLoader.defineClass(String, byte[], int, int).

从以下版本开始:

4.0

作者:

TODAY 2021/11/8 9:44

构造器概要

构造器

构造器	说明
DefineClassHelper()

方法概要

修饰符和类型	方法	说明
static Class<?>	defineClass(Class<?> neighbor, byte[] bcode)	Loads a class file by java.lang.invoke.MethodHandles.Lookup.
static Class<?>	defineClass(String className, byte[] b, ClassLoader loader)
static Class<?>	defineClass(String className, byte[] b, ClassLoader loader, ProtectionDomain protectionDomain)
static Class<?>	defineClass(String className, Class<?> neighbor, ClassLoader loader, ProtectionDomain domain, byte[] classFile)	Loads a class file by a given class loader.

从类继承的方法 java.lang.Object

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

构造器详细资料

DefineClassHelper

public DefineClassHelper()

方法详细资料

defineClass

public static Class<?> defineClass(Class<?> neighbor,
 byte[] bcode)
                            throws ReflectionException

Loads a class file by java.lang.invoke.MethodHandles.Lookup. It is obtained by using neighbor.

参数:

neighbor - a class belonging to the same package that the loaded class belogns to.

bcode - the bytecode.

抛出:

ReflectionException

defineClass

public static Class<?> defineClass(String className,
 byte[] b,
 ClassLoader loader)
                            throws CodeGenerationException

抛出:

CodeGenerationException

defineClass

public static Class<?> defineClass(String className,
 byte[] b,
 ClassLoader loader,
 ProtectionDomain protectionDomain)
                            throws CodeGenerationException

抛出:

CodeGenerationException

defineClass

public static Class<?> defineClass(String className,
 @Nullable
 Class<?> neighbor,
 ClassLoader loader,
 @Nullable
 ProtectionDomain domain,
 byte[] classFile)
                            throws CodeGenerationException

Loads a class file by a given class loader.

This first tries to use java.lang.invoke.MethodHandle to load a class. Otherwise, or if neighbor is null, this tries to use sun.misc.Unsafe to load a class. Then it tries to use a protected method in java.lang.ClassLoader via PrivilegedAction. Since the latter approach is not available any longer by default in Java 9 or later, the JVM argument --add-opens java.base/java.lang=ALL-UNNAMED must be given to the JVM.

 --add-opens java.base/java.lang=ALL-UNNAMED
 --add-opens java.base/java.util=ALL-UNNAMED
 --add-opens java.base/java.lang.reflect=ALL-UNNAMED
 

参数:

className - the name of the loaded class.

neighbor - the class contained in the same package as the loaded class.

loader - the class loader. It can be null if neighbor is not null and the JVM is Java 11 or later.

domain - if it is null, a default domain is used.

classFile - the bytecode for the loaded class.

抛出:

CodeGenerationException