JAVA数据库取数据万用方法
2009-03-21 12:24
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package util;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.util.Vector;
import java.util.logging.Level;
import java.util.logging.Logger;
/**
*
* @author Administrator
*/
public class DBAccess {
private static String Dr =
"com.microsoft.jdbc.sqlserver.SQLServerDriver";
private static String url =
"jdbc:microsoft:sqlserver://localhost:1433;databaseName=BookShop"; //创建Connection对象
public Connection getConnection() {
Connection conn = null;
try {
Class.forName(Dr);//创建驱动
conn = DriverManager.getConnection(url, "用户名", "密码");//创建数据库连接
} catch (ClassNotFoundException ex) {
Logger.getLogger(DBAccess.class.getName()).log (Level.SEVERE, null, ex);
} catch (SQLException ex) {
Logger.getLogger(DBAccess.class.getName()).log (Level.SEVERE, null, ex);
}
return conn;
}
//查询方法
//传入一个sql语句，返回一个Vector集合
public Vector inquiryFacility(String sql) {
Connection con;
Vector vc = new Vector();
ResultSet rs = null;
PreparedStatement st = null;
//得到数据库连接对象
con = this.getConnection();
//判断是否为空
if (con != null) {
try {
st = con.prepareCall(sql);
//执行sql语句
rs = st.executeQuery();
while (rs.next()) {
ResultSetMetaData rsmd =
rs.getMetaData();
//获得一行中有多少个字段
int numberOfColumns =
rsmd.getColumnCount();
Vector vt = new Vector();
//循环便利每一行的值
for (int i = 1; i <= numberOfColumns; i++) {
//将每一个字段的值加入vt集合中
vt.add(rs.getObject(i) );
}
//将获得的每一行的集合放到vc 集合中
vc.add(vt);
}
} catch (SQLException ex) {
Logger.getLogger(DBAccess.class.getNam e()).log(Level.SEVERE, null, ex);
} finally {
try {
//关闭连接
rs.close();
st.close();
con.close();
} catch (SQLException ex) {
Logger.getLogger(DBAccess.clas
s.getName()).log(Level.SEVERE, null, ex);
}
}
} else {
System.out.println("数据库连接错误");
}
//返回一个Vector对象
return vc;
}
public static void main(String[] args) {
//传入sql语句，获得查询结果
Vector vc = new DBAccess().inquiryFacility("sql语句");
//取出每一行数据
for(int i = 0;i < vc.size(); i++){
//取出每一列数据
for(int j = 0;j <
((Vector)vc.get(i)).size();j++){
System.out.print("\t"+((Vector)vc.get( i)).get(j));
}
System.out.println("");
}
}
}
运行的适合别忘了加载驱动包，上面的驱动是针对SQL server2005来用的，如果你用的是MySQL、oracle请把上面的驱动改掉，取出来的数据是Object类型的，别忘了转换类型！！！这个方法是我自己写的，有什么不足的地方，请把你宝贵的意见提出来！谢谢。