Package net.bytebuddy.asm

Class ClassVisitorFactory<T>

java.lang.Object

net.bytebuddy.asm.ClassVisitorFactory<T>

Type Parameters:

T - The type of the mapped class visitor.

@Enhance
public abstract class ClassVisitorFactory<T>
extends Object

A factory for wrapping a ClassVisitor in Byte Buddy's package namespace to a ClassVisitor in any other namespace. Note that this API does not allow for the passing of Attributes. which must be filtered or propagated past this translation. If the supplied visitors do not declare a method that Byte Buddy's version of ASM is aware of, an UnsupportedOperationException is thrown.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
protected static class	ClassVisitorFactory.AttributeTranslator	A method to wrap an Attribute.
protected static class	ClassVisitorFactory.ConstantArrayTranslator	A method to translate an array of constants from one namespace to another.
protected static class	ClassVisitorFactory.ConstantDynamicTranslator	A method to translate a ConstantDynamic from one namespace to another.
protected static class	ClassVisitorFactory.ConstantTranslator	A method to translate a constant value from one namespace to another.
protected static class	ClassVisitorFactory.CreateClassVisitorFactory<S>	A factory for creating a wrapper for a ClassVisitor.
protected static class	ClassVisitorFactory.FrameTranslator	A method to translate a stack map frame array from one namespace to another.
protected static class	ClassVisitorFactory.HandleTranslator	A method to translate a Handle from one namespace to another.
protected static class	ClassVisitorFactory.LabelArrayTranslator	A method to translate an array of Labels from one namespace to another.
protected static class	ClassVisitorFactory.LabelTranslator	A method to translate a Label from one namespace to another.
protected static class	ClassVisitorFactory.NullCheckedConstruction	An appender that performs a null-checked construction.
protected static class	ClassVisitorFactory.TypePathTranslator	A method to translate a TypePath type from one namespace to another.

Field Summary

Fields

Modifier and Type	Field	Description
private static final String	DELEGATE	The name of the delegate field containing an equivalent visitor.
private static final String	LABELS	The name of a map with labels that have been translated previously.
private final Class<?>	type	The type of the represented class visitor wrapper.
private static final String	WRAP	The name of the method that wraps a translated visitor, including a null check.

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	ClassVisitorFactory(Class<?> type)	Creates a new factory.

Method Summary

Modifier and Type	Method	Description
private static <T> T	doPrivileged(PrivilegedAction<T> action)	A proxy for java.security.AccessController#doPrivileged that is activated if available.
Class<?>	getType()	Returns the ClassVisitor type that this factory represents.
static <S> ClassVisitorFactory<S>	of(Class<S> classVisitor)	Returns a class visitor factory for the supplied ClassVisitor type.
static <S> ClassVisitorFactory<S>	of(Class<S> classVisitor, ByteBuddy byteBuddy)	Returns a class visitor factory for the supplied ClassVisitor type.
private static DynamicType	toAttributeWrapper(DynamicType.Builder<?> builder, Class<?> source, Class<?> target, TypeDescription sourceWrapper, TypeDescription targetWrapper)	Creates a wrapper type for an Attribute to pass attribues along a visitor chain.
private static MethodCall.ArgumentLoader.Factory	toConvertedParameter(TypeDescription source, Class<?> target, String method, int offset, boolean virtual)	Creates an argument loader for a method parameter that requires conversion.
private static DynamicType.Builder<?>	toMethodVisitorBuilder(ByteBuddy byteBuddy, Class<?> sourceVisitor, Class<?> targetVisitor, Class<?> sourceTypePath, Class<?> targetTypePath, Class<?> sourceLabel, Class<?> targetLabel, Class<?> sourceType, Class<?> targetType, Class<?> sourceHandle, Class<?> targetHandle, Class<?> sourceConstantDynamic, Class<?> targetConstantDynamic)	Creates a builder for a method visitor type.
private static DynamicType.Builder<?>	toVisitorBuilder(ByteBuddy byteBuddy, Class<?> sourceVisitor, Class<?> targetVisitor, Class<?> sourceTypePath, Class<?> targetTypePath, Implementation appendix)	Creates a builder for a visitor type.
abstract org.objectweb.asm.ClassVisitor	unwrap(T classVisitor)	Unwraps an instance of the supplied class visitor as a ClassVisitor.
abstract T	wrap(org.objectweb.asm.ClassVisitor classVisitor)	Wraps a ClassVisitor within an instance of the supplied class visitor type.

Methods inherited from class java.lang.Object

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

Field Details

DELEGATE

private static final String DELEGATE

The name of the delegate field containing an equivalent visitor.

See Also:

• Constant Field Values

LABELS

private static final String LABELS

The name of a map with labels that have been translated previously.

See Also:

• Constant Field Values

WRAP

private static final String WRAP

The name of the method that wraps a translated visitor, including a null check.

See Also:

• Constant Field Values

type

private final Class<?> type

The type of the represented class visitor wrapper.

Constructor Details

ClassVisitorFactory

protected ClassVisitorFactory(Class<?> type)

Creates a new factory.

Parameters:

type - The type of the represented class visitor wrapper.

Method Details

getType

public Class<?> getType()

Returns the ClassVisitor type that this factory represents.

Returns:

The ClassVisitor type that this factory represents.

of

public static <S> ClassVisitorFactory<S> of(Class<S> classVisitor)

Returns a class visitor factory for the supplied ClassVisitor type.

Type Parameters:

S - The type of the class visitor to map to.

Parameters:

classVisitor - The type of the translated class visitor.

Returns:

A factory for wrapping ClassVisitors in Byte Buddy's and the supplied package namespace.

of

public static <S> ClassVisitorFactory<S> of(Class<S> classVisitor,
 ByteBuddy byteBuddy)

Returns a class visitor factory for the supplied ClassVisitor type.

Type Parameters:

S - The type of the class visitor to map to.

Parameters:

classVisitor - The type of the translated ClassVisitor.

byteBuddy - The Byte Buddy instance to use.

Returns:

A factory for wrapping ClassVisitors in Byte Buddy's and the supplied package namespace.

doPrivileged

@Enhance
private static <T> T doPrivileged(PrivilegedAction<T> action)

A proxy for java.security.AccessController#doPrivileged that is activated if available.

Type Parameters:

T - The type of the action's resolved value.

Parameters:

action - The action to execute from a privileged context.

Returns:

The action's resolved value.

toVisitorBuilder

private static DynamicType.Builder<?> toVisitorBuilder(ByteBuddy byteBuddy,
 Class<?> sourceVisitor,
 Class<?> targetVisitor,
 @MaybeNull
 Class<?> sourceTypePath,
 @MaybeNull
 Class<?> targetTypePath,
 Implementation appendix)
                                                throws Exception

Creates a builder for a visitor type.

Parameters:

byteBuddy - The Byte Buddy instance to use.

sourceVisitor - The visitor type to map from.

targetVisitor - The visitor type to map to.

sourceTypePath - The TypePath source type.

targetTypePath - The TypePath target type.

appendix - The implementation to append to the constructor.

Returns:

The created builder.

Throws:

Exception - If an exception occurs.

toMethodVisitorBuilder

private static DynamicType.Builder<?> toMethodVisitorBuilder(ByteBuddy byteBuddy,
 Class<?> sourceVisitor,
 Class<?> targetVisitor,
 @MaybeNull
 Class<?> sourceTypePath,
 @MaybeNull
 Class<?> targetTypePath,
 @MaybeNull
 Class<?> sourceLabel,
 @MaybeNull
 Class<?> targetLabel,
 @MaybeNull
 Class<?> sourceType,
 @MaybeNull
 Class<?> targetType,
 @MaybeNull
 Class<?> sourceHandle,
 @MaybeNull
 Class<?> targetHandle,
 @MaybeNull
 Class<?> sourceConstantDynamic,
 @MaybeNull
 Class<?> targetConstantDynamic)
                                                      throws Exception

Creates a builder for a method visitor type.

Parameters:

byteBuddy - The Byte Buddy instance to use.

sourceVisitor - The visitor type to map from.

targetVisitor - The visitor type to map to.

sourceTypePath - The TypePath source type.

targetTypePath - The TypePath target type.

sourceLabel - The Label source type.

targetLabel - The Label target type.

sourceType - The Type source type.

targetType - The Type target type.

sourceHandle - The Handle source type.

targetHandle - The Handle target type.

sourceConstantDynamic - The ConstantDynamic source type.

targetConstantDynamic - The ConstantDynamic target type.

Returns:

The created builder.

Throws:

Exception - If an exception occurs.

toConvertedParameter

private static MethodCall.ArgumentLoader.Factory toConvertedParameter(TypeDescription source,
 Class<?> target,
 String method,
 int offset,
 boolean virtual)

Creates an argument loader for a method parameter that requires conversion.

Parameters:

source - The source type.

target - The target type.

method - The name of the method.

offset - The parameter offset

virtual - true if the invoked method is virtual.

Returns:

An appropriate argument loader factory.

toAttributeWrapper

private static DynamicType toAttributeWrapper(DynamicType.Builder<?> builder,
 Class<?> source,
 Class<?> target,
 TypeDescription sourceWrapper,
 TypeDescription targetWrapper)
                                       throws Exception

Creates a wrapper type for an Attribute to pass attribues along a visitor chain.

Parameters:

builder - The builder to use for the wrapper type.

source - The Attribute type in the original namespace.

target - The Attribute type in the targeted namespace.

sourceWrapper - The wrapper type for the Attribute type in the original namespace.

targetWrapper - The wrapper type for the Attribute type in the targeted namespace.

Returns:

The created dynamic type.

Throws:

Exception - If the dynamic type cannot be built.

wrap

public abstract T wrap(org.objectweb.asm.ClassVisitor classVisitor)

Wraps a ClassVisitor within an instance of the supplied class visitor type.

Parameters:

classVisitor - The class visitor to wrap.

Returns:

A class visitor that wraps the supplied class visitor.

unwrap

public abstract org.objectweb.asm.ClassVisitor unwrap(T classVisitor)

Unwraps an instance of the supplied class visitor as a ClassVisitor.

Parameters:

classVisitor - The class visitor to unwrap.

Returns:

A class visitor that unwraps the supplied class visitor.