我正在尝试创建自己的智能冰箱概念设计版本，该设计本质上是在外部USB磅秤上发送食品杂货的加权值（例如，我将使用6个鸡蛋的纸箱）。它将6个鸡蛋存储在名为“ fridge”的MySQL数据库表中，每次删除鸡蛋时，它将在数据库表“购物清单”中添加一个鸡蛋。购物清单表将与在线杂货店API通信（我正在使用Tesco的API：https://devportal.tescolabs.com/products/56c73300d73fa303ed060001）。到目前为止，我已经取得了进展，一旦鸡蛋的重量落在我拥有的值数组之间，我就能够获得鸡蛋的重量以打印出“体重变化”（如下面我的主班级所示）。组。基本上，我停留在项目的下一部分，该部分每次权重发生变化时都将值写入数据库表。我有数据库连接，并且有一个查询，一旦重量与EggsWeight整数相同，就会在其中插入鸡蛋值，但是我希望数据库根据重量变化来一致地更新数量值。是否有人对此有任何指导或建议？任何反馈将不胜感激。
import java.io.Console;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.util.List;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.usb.UsbConfiguration;
import javax.usb.UsbDevice;
import javax.usb.UsbDeviceDescriptor;
import javax.usb.UsbEndpoint;
import javax.usb.UsbException;
import javax.usb.UsbHostManager;
import javax.usb.UsbHub;
import javax.usb.UsbInterface;
import javax.usb.UsbPipe;
import javax.usb.UsbServices;
import javax.usb.event.UsbPipeDataEvent;
import javax.usb.event.UsbPipeErrorEvent;
import javax.usb.event.UsbPipeListener;
public class UsbScale implements UsbPipeListener {
private final UsbDevice device;
private UsbInterface iface;
private UsbPipe pipe;
private byte[] data = new byte[6];
private UsbScale(UsbDevice device) {
this.device = device;
}
public static void main(String[] args) throws UsbException {
UsbScale scale = UsbScale.findScale();
scale.open();
try {
for (boolean i = true; i; i = true) {
scale.syncSubmit();
}
} finally {
scale.close();
}
}
public static UsbScale findScale() throws UsbException {
UsbServices services = UsbHostManager.getUsbServices();
UsbHub rootHub = services.getRootUsbHub();
// Dymo M5 Scale:
UsbDevice device = findDevice(rootHub, (short) 0x0922, (short) 0x8003);
// Dymo M25 Scale:
if (device == null) {
device = findDevice(rootHub, (short) 0x0922, (short) 0x8005);
}
if (device == null) {
return null;
}
return new UsbScale(device);
}
private static UsbDevice findDevice(UsbHub hub, short vendorId, short productId) {
for (UsbDevice device : (List<UsbDevice>) hub.getAttachedUsbDevices()) {
UsbDeviceDescriptor desc = device.getUsbDeviceDescriptor();
if (desc.idVendor() == vendorId && desc.idProduct() == productId) {
return device;
}
if (device.isUsbHub()) {
device = findDevice((UsbHub) device, vendorId, productId);
if (device != null) {
return device;
}
}
}
return null;
}
private void open() throws UsbException {
UsbConfiguration configuration = device.getActiveUsbConfiguration();
iface = configuration.getUsbInterface((byte) 0);
// this allows us to steal the lock from the kernel
iface.claim(usbInterface -> true);
final List<UsbEndpoint> endpoints = iface.getUsbEndpoints();
pipe = endpoints.get(0).getUsbPipe(); // there is only 1 endpoint
pipe.addUsbPipeListener(this);
pipe.open();
}
private void syncSubmit() throws UsbException {
pipe.syncSubmit(data);
}
public void close() throws UsbException {
pipe.close();
iface.release();
}
@Override
public void dataEventOccurred(UsbPipeDataEvent upde) {
boolean empty = data[1] == 2;
boolean overweight = data[1] == 6;
boolean negative = data[1] == 5;
boolean grams = data[2] == 2;
int scalingFactor = data[3];
int weight = (data[4] & 0xFF) + (data[5] << 8);
// int phoneWeights[] = new int[5];
// int minWeight = 142;
//int previous weight=0;
boolean EggsOnScale = false;
int[] EggsWeight = { 440, 460 };
int[] OneEgg = { 60, 75 };
int count = 0;
int oldweight=0;
//oldweight = weight;
if (oldweight == weight) {
// do nothing
} else {
System.out.println("Weight Changes");
/* write DB
//if (weight < oldweight){
//then something was taken off
*
* remove equivalent amount of eggs from db.fridge.
//if(db.frdige == 0 eggs){
//order eggs
}
if(weight > oldweight){
somebody put eggs in the fridge.
}
*
*
*
}*/
oldweight=weight;
}
if (weight != oldweight) {
while (count <= 5000) {
count++;
}
while (count < 5)
weight = count++;
/*
for(int i=0, i=Length(phoneWeights); i++) { phoneWeights[i] = minweight+i; }
*/
/*
* System.out.println(String.format("Weight = %,.1f%s", scaleWeight(weight,
* scalingFactor), grams ? "g" : "oz"));
*/
System.out.println("My Weight: " + weight);
/*if(newweight != oldweight) {
oldweight = newweight;
write to db shopping list;
}*/
if(EggsWeight[0] <= weight && weight <= EggsWeight[1]) {
EggsOnScale = true;
System.out.println("6 Eggs on scale");
// write one phone to table in db.
try {
// create a mysql database connection
String myDriver = "com.mysql.jdbc.Driver";
String myUrl = "jdbc:mysql://localhost:3306/smartfridge?autoReconnect=true&useSSL=false";
Class.forName(myDriver);
Connection conn = DriverManager.getConnection(myUrl, "root", "admin");
// the mysql insert statement
String query = " insert into fridge (name, UnitOfSale, ContentsQuantity, department, AverageSellingUnitWeight)"
+ " values (?, ?, ?, ?, ?)";
// create the mysql insert preparedstatement
PreparedStatement preparedStmt = conn.prepareStatement(query);
preparedStmt.setString(1, "Eggs");
preparedStmt.setInt(2, 1);
preparedStmt.setInt(3, 6);
preparedStmt.setString(4, "Milk, Butter & Eggs");
preparedStmt.setBoolean(5, EggsOnScale);
// execute the preparedstatement
preparedStmt.execute();
} catch (Exception e) {
//e.printStackTrace();
}
} else{
/*if(EggsWeight[0] - OneEgg[0] <= weight && weight <= EggsWeight[1] - OneEgg[1]) {
String query =" update fridge set ContentsQuantity = ContentsQuantity -1 where name ='Eggs' and ContentsQuantity > 0 ";
//System.out.println(ContentsQuantity + "Eggs On Scale");*/
oldweight = weight;
}
}
}
private double scaleWeight(int weight, int scalingFactor) {
return weight * Math.pow(10, scalingFactor);
}
@Override
public void errorEventOccurred(UsbPipeErrorEvent upee) {
Logger.getLogger(UsbScale.class.getName()).log(Level.SEVERE, "Scale Error", upee);
}
}