You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: boxing.go
    path of file: ./repos/jvm.go/native/box
    
    the code of the file until where you have to start completion: package box

import (
	"fmt"

	"github.com/zxh0/jvm.go/rtda"
	"github.com/zxh0/jvm.go/rtda/heap"
)

func Unbox(obj *heap.Object, primitiveDescriptor string) heap.Slot {
	return obj.GetFieldValue("value", primitiveDescriptor)
}

// boxing primitive types
// primitive value 
    
func Box(frame *rtda.Frame, primitiveDescriptor byte) {
	switch primitiveDescriptor {
	case 'Z':
		_callValueOf(frame, "Z", "java/lang/Boolean")
	case 'B':
		_callValueOf(frame, "B", "java/lang/Byte")
	case 'C':
		_callValueOf(frame, "C", "java/lang/Character")
	case 'S':
		_callValueOf(frame, "S", "java/lang/Short")
	case 'I':
		_callValueOf(frame, "I", "java/lang/Integer")
	case 'J':
		_callValueOf(frame, "J", "java/lang/Long")
	case 'F':
		_callValueOf(frame, "F", "java/lang/Float")
	case 'D':
		_callValueOf(frame, "D", "java/lang/Double")
	default:
		panic(fmt.Errorf("not primitive type: %v", primitiveDescriptor))
	}
}