问题
I am trying to fetch some records from a txt file and put those in Database in the following Java Program
package Java_Demo;
import java.sql.*;
import java.util.*;
import java.io.*;
public class Jdbc_Demo {
public static void main(String ...args)throws ClassNotFoundException,SQLException,FileNotFoundException {
FileInputStream fin=new FileInputStream("C:/Users/steve-pc/Desktop/Employees.txt");
Scanner s=new Scanner(fin);
s.useDelimiter(",|\\n");
Class.forName("oracle.jdbc.driver.OracleDriver");
Connection con=DriverManager.getConnection("jdbc:oracle:thin:@172.22.22.131:1521:orcl","Demo","demo");
while(s.hasNext())
{
PreparedStatement st=con.prepareStatement("Insert into Employee values(?,?,?)");
String name=s.next();
int id=s.nextInt();
int sal=s.nextInt();
st.setString(1,name);
st.setInt(2,id);
st.setInt(3,sal);
int result=st.executeUpdate();
System.out.println("Records Changed: "+ result);
}
con.close();
}
}
The txt file from which I am fetching the data has following format
Steve,12349,550000
Mark,54321,250000
Bill,65478,350000
Additionally the EMPLOYEE table has following format
Name Id Salary
Varachar2 Number Number
But the code is generating following ERROR
Exception in thread "main" java.util.InputMismatchException
at java.util.Scanner.throwFor(Scanner.java:909)
at java.util.Scanner.next(Scanner.java:1530)
at java.util.Scanner.nextInt(Scanner.java:2160)
at java.util.Scanner.nextInt(Scanner.java:2119)
at Java_Demo.Jdbc_Demo.main(Jdbc_Demo.java:24)
回答1:
Make the change as below:
public class ScannerTest {
public static void main(String ...args)throws ClassNotFoundException,SQLException,FileNotFoundException {
File f =new File("/home/rahul/Desktop/emp.txt");
Scanner s=new Scanner(f);
Class.forName("oracle.jdbc.driver.OracleDriver");
Connection con=DriverManager.getConnection("jdbc:oracle:thin:@172.22.22.131:1521:orcl","Demo","demo");
while(s.hasNext())
{
PreparedStatement st=con.prepareStatement("Insert into Employee values(?,?,?)");
String rcd = s.next();
Scanner s1 = new Scanner(rcd);
s1.useDelimiter(",|\\n");
String name=s1.next();
int id=s1.nextInt();
int sal=s1.nextInt();
st.setString(1,name);
st.setInt(2,id);
st.setInt(3,sal);
int result=st.executeUpdate();
System.out.println("Records Changed: "+ result);
}
con.close();
}
}
}
回答2:
s.nextInt(); is giving error for you. Because the scanner next cannot be converted into integer. I would suggest, you use s.next for all three and then Integer.parseInt(String) method to convert them into int
回答3:
I wonder if you have whitespace in your file?
If so, you can use something like this to ignore it
scanner.useDelimiter("\\s*,\\s*|\\n");
Or read each token as a string and then tidy and convert to int.
来源：https://stackoverflow.com/questions/23425191/exception-in-thread-main-java-util-inputmismatchexception