Package javassist.util.proxy

Class DefineClassHelper

java.lang.Object

javassist.util.proxy.DefineClassHelper

public class DefineClassHelper
extends Object

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

Since:

3.22

Method Summary

Modifier and Type	Method	Description
static Class<?>	toClass(Class<?> neighbor, byte[] bcode)	Loads a class file by java.lang.invoke.MethodHandles.Lookup.
static Class<?>	toClass(MethodHandles.Lookup lookup, byte[] bcode)	Loads a class file by java.lang.invoke.MethodHandles.Lookup.
static Class<?>	toClass(String className, Class<?> neighbor, ClassLoader loader, ProtectionDomain domain, byte[] bcode)	Loads a class file by a given class loader.

Methods inherited from class java.lang.Object

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

Method Details

toClass

public static Class<?> toClass(String className,
 Class<?> neighbor,
 ClassLoader loader,
 ProtectionDomain domain,
 byte[] bcode)
                        throws CannotCompileException

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. If this JVM argument cannot be given, toPublicClass(String,byte[]) should be used instead.

Parameters:

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.

bcode - the bytecode for the loaded class.

Throws:

CannotCompileException

Since:

3.22

toClass

public static Class<?> toClass(Class<?> neighbor,
 byte[] bcode)
                        throws CannotCompileException

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

Parameters:

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

bcode - the bytecode.

Throws:

CannotCompileException

Since:

3.24

toClass

public static Class<?> toClass(MethodHandles.Lookup lookup,
 byte[] bcode)
                        throws CannotCompileException

Loads a class file by java.lang.invoke.MethodHandles.Lookup. It can be obtained by MethodHandles.lookup() called from somewhere in the package that the loaded class belongs to.

Parameters:

bcode - the bytecode.

Throws:

CannotCompileException

Since:

3.24