An adapter is an interface converter that can be an independent hardware interface device that allows hardware or electronic interfaces to be connected to other hardware or electronic interfaces, or it can be an information interface. For example, power adapters, tripod base adapter components, USB and serial port adapter devices, etc. In a computer, an adapter is usually built into a card that can be inserted into a slot on the motherboard (also external), and the adapter information in the card is exchanged with the processor and the devices supported by the adapter. A power adapter is a power conversion device for small portable electronic devices and electronic appliances. It is generally composed of a shell, a power transformer, and a rectifier circuit. According to its output type, it can be divided into AC output type and DC output type; According to the connection method, it can be divided into plug-in wall type and desktop type. Due to the lack of batteries, power adapters are particularly important for mobile PCs. Most mobile PC power adapters can automatically detect 100-240V AC (50/60Hz). Basically, all mobile PCs have external power sources connected to the host using a single cable, which can reduce the size and weight of the host. Only a few models have built-in power sources inside the host. There is a nameplate on the power adapter, which indicates indicators such as power, input/output voltage, and current flow. Special attention should be paid to the range of input voltage, which is known as the "travel power adapter". When an MBean is registered with an MBean server, it requires protocols for interacting with these MBeans and retrieving information for requests made from management applications. This is enabled through a protocol adapter, which can convert management application data into standard protocol information