question: private void buildField ( ClassWriter classWriter , List < SFieldDef > fields ) { for ( SFieldDef field : fields ) { FieldVisitor fieldVisitor = classWriter . visitField ( acc ( field . modifiers ( ) ) , field . name ( ) , typeToDesc ( field . type ( ) ) , null , null ) ; for ( SAnno anno : field . annos ( ) ) { AnnotationVisitor annotationVisitor = fieldVisitor . visitAnnotation ( typeToDesc ( anno . type ( ) ) , annotationIsVisible ( anno ) ) ; buildAnnotation ( annotationVisitor , anno ) ; } fieldVisitor . visitEnd ( ) ; } }
target:  build field and its annotations.