1
好吧..所以我做了一个小应用程序，它连接到我的数据库。我可以读出一个excel文件并将这些文件存储到一个数组中。 我的数据库有多个表。我可以填写一张桌子，但是当我想填写另一张桌子时，它将不起作用。我的堆栈跟踪中有一堆红线，我无法弄清楚该怎么做..所以我绝望地来到了这里，希望得到一些帮助。我的第二张桌子没有被填充数据
我的程序由一个主的：
public static void main(String[] args){
CustomerMC cmc = new CustomerMC();
ArrayList<Customer> customers = new ArrayList<>();
ArrayList<Order> orders = new ArrayList<>();
ArrayList<ArrayList> gay = new ArrayList<>();
try {
try (FileInputStream file = new FileInputStream(new File("C:/Users/Wout/Desktop/ProjectTest.xlsx"))) {
XSSFWorkbook wb = new XSSFWorkbook(file);
XSSFSheet sh = wb.getSheetAt(0);
Iterator<Row> rowIterator = sh.iterator();
while(rowIterator.hasNext()) {
Row row = rowIterator.next();
Iterator<Cell> cellIterator = row.cellIterator();
int counter = 0;
int cid = 0;
int OrderID = 0;
String name = "";
String purchase = "";
String age = "";
String product = "";
while (cellIterator.hasNext() && row.getRowNum() != 0) {
Cell cell = cellIterator.next();
counter++;
switch (counter) {
case 1:
cid = (int)cell.getNumericCellValue();
break;
case 2:
name = cell.getStringCellValue();
break;
case 3:
purchase = cell.getStringCellValue();
break;
case 4:
age = "" + cell.getNumericCellValue();
break;
case 5:
OrderID = (int)cell.getNumericCellValue();
break;
case 6:
product = "" + cell.getStringCellValue();
break;
case 7:
cid = (int)cell.getNumericCellValue();
break;
}
}
if(row.getRowNum() != 0) {
Customer customer = new Customer(cid,name,purchase,age);
Order order = new Order(OrderID, product, cid);
customers.add(customer);
orders.add(order);
gay.add(customers);
gay.add(orders);
}
}
}
} catch (FileNotFoundException ex) {
System.out.println("File has not been found");
} catch (IOException ex) {
System.out.println("An error has occured");
}
for(Customer customer : customers){
for(Order order : orders) {
System.out.println(order.toString());
cmc.insertOrder(""+order.getOrderid(), order.getProduct(), ""+customer.getCid());
}
System.out.println(customer.toString());
cmc.insertCustomer(""+customer.getCid(), customer.getName(), customer.getPurchase(), customer.getAge());
}
}
两个容器类：
public class Customer {
private int cid;
private String name;
private String purchase;
private String age;
public Customer(int cid, String name, String purchase, String age) {
this.cid = cid;
this.name = name;
this.purchase = purchase;
this.age = age;
}
public int getCid() {
return cid;
}
public void setCid(int cid) {
this.cid = cid;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getPurchase() {
return purchase;
}
public void setPurchase(String purchase) {
this.purchase = purchase;
}
public String getAge() {
return age;
}
public void setAge(String age) {
this.age = age;
}
@Override
public String toString() {
return "" + cid + " ; "+ name + " ; " + purchase + " ; " + age;
----------------------------------------------------------------------------
public class Order {
private int orderid;
private String product;
private int cid;
public Order(int orderid, String product, int cid) {
this.orderid = orderid;
this.product = product;
this.cid = cid;
}
public int getOrderid() {
return orderid;
}
public void setOrderid(int orderid) {
this.orderid = orderid;
}
public String getProduct() {
return product;
}
public void setProduct(String product) {
this.product = product;
}
public int getCid() {
return cid;
}
public void setCid(int cid) {
this.cid = cid;
}
@Override
public String toString() {
return "" + orderid + " ; " + product + " ; " + cid;
}
我的模型类客户提供查询，例如：
public class CustomerMC {
private Connection connection;
private PreparedStatement pst;
String query;
ResultSet rs;
public CustomerMC(){
try{
connection = SimpleDataSourceV2.getConnection();
}
catch(SQLException e){
System.out.println("Connection failure");
e.printStackTrace();
}
}
public String insertCustomer(String cid, String name, String purchase, String age) {
String returning = null;
try {
query = "insert into CustomerService values(?,?,?,?);";
pst = connection.prepareStatement(query);
pst.setInt(1, Integer.parseInt(cid));
pst.setString(2, name);
pst.setString(3, purchase);
pst.setString(4, age);
int response = pst.executeUpdate();
returning = response +" Records has/have been edited";
} catch (SQLException e) {
returning = "An error has occured";
}
return returning;
}
public String insertOrder(String orderid, String product, String id) {
String returning = null;
try {
query = "insert into Order values(?,?,?);";
pst = connection.prepareStatement(query);
pst.setInt(1, Integer.parseInt(orderid));
pst.setString(2, product);
pst.setInt(3, Integer.parseInt(id));
int response = pst.executeUpdate();
returning = response +" Records has/have been edited";
} catch (SQLException e) {
System.out.println();
e.printStackTrace();
}
return returning;
}
第一类;这是客户表填写完美。它打印出它必须做的事情。但是，订单表，第二个，没有。我得到的输出如下：
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
at com.mysql.jdbc.Util.getInstance(Util.java:386)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1053)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4120)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4052)
at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2503)
at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2664)
at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2794)
at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:2155)
at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:2458)
at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:2375)
at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:2359)
at p4project.CustomerMC.insertOrder(CustomerMC.java:65)
at p4project.Main.main(Main.java:102)
com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'Order values(2,'Couch',1)' at line 1
我希望有人能帮忙，任何帮助都是值得欢迎的。
真诚，
双
我会建议您包括您插入的列名，它既帮助文档，还可以帮助的情况下，有时表是用不同的列顺序重新创建一个它会导致各种未来的问题。 –