数据库连接问题

package com.castit.it;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Date;

public class TestJDBC2 {

/**
* @param args
*/
 public static void main(String[] args) {
  if(args.length != 4) {
   System.out.println("格式错误!");
   System.exit(-1);
  }
  int id = 0;
  try {
   id = Integer.parseInt(args[0]);
  } catch (NumberFormatException e1) {
   System.out.println("格式错误!");
   System.exit(-1);
  }
  String typeName = args[1];
  int days = Integer.parseInt(args[2]);
  float fk = Float.parseFloat(args[3]);
  //ResultSet rs = null;
  PreparedStatement stmt = null;
  Connection conn = null;
  try {
   Class.forName("com.microsoft.jdbc.sqlserver.SQLServerDriver");
   conn = DriverManager.getConnection("jdbc:microsoft:sqlserver://localhost:1433;DatabaseName=db_library","sa","");
   stmt = conn.prepareStatement("insert into tb_bookType  values(?,?,?,?)");
   //rs = stmt.executeQuery("select * from tb_bookInfo");
   /*while(rs.next()) {
   System.out.println(rs.getString("bookname"));
   //System.out.println(rs.getInt("price"));
   }*/
   stmt.setInt(1, id);
   stmt.setString(2,typeName);
   stmt.setInt(3,days);
   stmt.setFloat(4,fk);
   stmt.executeUpdate();
  } catch (ClassNotFoundException e) {
  // TODO Auto-generated catch block
   e.printStackTrace();
  } catch (SQLException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
  }finally {
   try {
    /*if(rs != null) {
     rs.close();
    }*/
    if(stmt != null) {
     stmt.close();
    }
     if(conn != null) {
      conn.close();
     }
   } catch (SQLException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
   }
  }

 }
 
}
 
 此时会提示这样的错误“仅当使用了列的列表，并且 IDENTITY_INSERT 为 ON 时，才能在表 'tb_bookType' 中为标识列指定显式值。”所以应将

stmt = conn.prepareStatement("insert into tb_bookType values(?,?,?,?)");   改为   stmt = conn.prepareStatement("insert into tb_bookType(id,typeName,days,fk) values(?,?,?,?)"); 此时有提示错误 “当 IDENTITY_INSERT 设置为 OFF 时，不能向表 'tb_bookType' 中的标识列插入显式值。” 故还应改为 stmt = conn.prepareStatement("set identity_insert tb_bookType ON insert into tb_bookType(id,typeName,days,fk) values(?,?,?,?)");   此时插入数据正常