package net.bytebuddy.implementation.attribute;
import lombok.EqualsAndHashCode;
import net.bytebuddy.description.annotation.AnnotationDescription;
import net.bytebuddy.description.field.FieldDescription;
import net.bytebuddy.description.type.TypeDescription;
import org.objectweb.asm.FieldVisitor;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
/**
* An appender that writes attributes or annotations to a given ASM {@link org.objectweb.asm.FieldVisitor}.
*/
public interface FieldAttributeAppender {
/**
* Applies this attribute appender to a given field visitor.
*
* @param fieldVisitor The field visitor to which the attributes that are represented by this attribute appender are written to.
* @param fieldDescription The description of the field to which the field visitor belongs to.
* @param annotationValueFilter The annotation value filter to apply when writing annotations.
*/
void apply(FieldVisitor fieldVisitor, FieldDescription fieldDescription, AnnotationValueFilter annotationValueFilter);
/**
* A field attribute appender that does not append any attributes.
*/
enum NoOp implements FieldAttributeAppender, Factory {
/**
* The singleton instance.
*/
INSTANCE;
@Override
public FieldAttributeAppender make(TypeDescription typeDescription) {
return this;
}
@Override
public void apply(FieldVisitor fieldVisitor, FieldDescription fieldDescription, AnnotationValueFilter annotationValueFilter) {
/* do nothing */
}
}
/**
* A factory that creates field attribute appenders for a given type.
*/
interface Factory {
/**
* Returns a field attribute appender that is applicable for a given type description.
*
* @param typeDescription The type for which a field attribute appender is to be applied for.
* @return The field attribute appender which should be applied for the given type.
*/
FieldAttributeAppender make(TypeDescription typeDescription);
/**
* A field attribute appender factory that combines several field attribute appender factories to be
* represented as a single factory.
*/
@EqualsAndHashCode
class Compound implements Factory {
/**
* The factories that this compound factory represents in their application order.
*/
private final List<Factory> factories;
/**
* Creates a new compound field attribute appender factory.
*
* @param factory The factories to represent in the order of their application.
*/
public Compound(Factory... factory) {
this(Arrays.asList(factory));
}
/**
* Creates a new compound field attribute appender factory.
*
* @param factories The factories to represent in the order of their application.
*/
public Compound(List<? extends Factory> factories) {
this.factories = new ArrayList<Factory>();
for (Factory factory : factories) {
if (factory instanceof Compound) {
this.factories.addAll(((Compound) factory).factories);
} else if (!(factory instanceof NoOp)) {
this.factories.add(factory);
}
}
}
@Override
public FieldAttributeAppender make(TypeDescription typeDescription) {
List<FieldAttributeAppender> fieldAttributeAppenders = new ArrayList<FieldAttributeAppender>(factories.size());
for (Factory factory : factories) {
fieldAttributeAppenders.add(factory.make(typeDescription));
}
return new FieldAttributeAppender.Compound(fieldAttributeAppenders);
}
}
}
/**
* An attribute appender that writes all annotations that are declared on a field.
*/
enum ForInstrumentedField implements FieldAttributeAppender, Factory {
/**
* The singleton instance.
*/
INSTANCE;
@Override
public void apply(FieldVisitor fieldVisitor, FieldDescription fieldDescription, AnnotationValueFilter annotationValueFilter) {
AnnotationAppender annotationAppender = new AnnotationAppender.Default(new AnnotationAppender.Target.OnField(fieldVisitor));
annotationAppender = fieldDescription.getType().accept(AnnotationAppender.ForTypeAnnotations.ofFieldType(annotationAppender, annotationValueFilter));
for (AnnotationDescription annotation : fieldDescription.getDeclaredAnnotations()) {
annotationAppender = annotationAppender.append(annotation, annotationValueFilter);
}
}
@Override
public FieldAttributeAppender make(TypeDescription typeDescription) {
return this;
}
}
/**
* Appends an annotation to a field. The visibility of the annotation is determined by the annotation type's
* {@link java.lang.annotation.RetentionPolicy} annotation.
*/
@EqualsAndHashCode
class Explicit implements FieldAttributeAppender, Factory {
/**
* The annotations that this appender appends.
*/
private final List<? extends AnnotationDescription> annotations;
/**
* Creates a new annotation attribute appender for explicit annotation values. All values, including default values, are copied.
*
* @param annotations The annotations to be appended to the field.
*/
public Explicit(List<? extends AnnotationDescription> annotations) {
this.annotations = annotations;
}
@Override
public void apply(FieldVisitor fieldVisitor, FieldDescription fieldDescription, AnnotationValueFilter annotationValueFilter) {
AnnotationAppender appender = new AnnotationAppender.Default(new AnnotationAppender.Target.OnField(fieldVisitor));
for (AnnotationDescription annotation : annotations) {
appender = appender.append(annotation, annotationValueFilter);
}
}
@Override
public FieldAttributeAppender make(TypeDescription typeDescription) {
return this;
}
}
/**
* A field attribute appender that combines several method attribute appenders to be represented as a single
* field attribute appender.
*/
@EqualsAndHashCode
class Compound implements FieldAttributeAppender {
/**
* The field attribute appenders this appender represents in their application order.
*/
private final List<FieldAttributeAppender> fieldAttributeAppenders;
/**
* Creates a new compound field attribute appender.
*
* @param fieldAttributeAppender The field attribute appenders that are to be combined by this compound appender
* in the order of their application.
*/
public Compound(FieldAttributeAppender... fieldAttributeAppender) {
this(Arrays.asList(fieldAttributeAppender));
}
/**
* Creates a new compound field attribute appender.
*
* @param fieldAttributeAppenders The field attribute appenders that are to be combined by this compound appender
* in the order of their application.
*/
public Compound(List<? extends FieldAttributeAppender> fieldAttributeAppenders) {
this.fieldAttributeAppenders = new ArrayList<FieldAttributeAppender>();
for (FieldAttributeAppender fieldAttributeAppender : fieldAttributeAppenders) {
if (fieldAttributeAppender instanceof Compound) {
this.fieldAttributeAppenders.addAll(((Compound) fieldAttributeAppender).fieldAttributeAppenders);
} else if (!(fieldAttributeAppender instanceof NoOp)) {
this.fieldAttributeAppenders.add(fieldAttributeAppender);
}
}
}
@Override
public void apply(FieldVisitor fieldVisitor, FieldDescription fieldDescription, AnnotationValueFilter annotationValueFilter) {
for (FieldAttributeAppender fieldAttributeAppender : fieldAttributeAppenders) {
fieldAttributeAppender.apply(fieldVisitor, fieldDescription, annotationValueFilter);
}
}
}
}