连接数据库的DBUtils工具类

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

public class DBUtils {
static{
try {
Class.forName("oracle.jdbc.driver.OracleDriver");
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public static Connection getConnection() throws SQLException{
String url = "jdbc:oracle:thin:@10.25.116.138:1521:orcl";
Connection conn = DriverManager.getConnection(url, "scott", "tiger");
return conn;
}
public static void close(PreparedStatement ps){
if(ps != null){
try {
ps.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
public static void close(ResultSet rs){
if(rs != null){
try {
rs.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
public static void close(Connection conn){
if(conn != null){
try {
conn.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}

public static void main(String[] args) {

String answer = "";
try {
Connection conn = DBUtils.getConnection();
StringBuilder sql = new StringBuilder("select name from t_emp");
PreparedStatement ps = conn.prepareStatement(sql.toString());
ResultSet rs = ps.executeQuery();
while (rs.next()) {
answer += rs.getString("name");
}
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
System.out.println("answer = " + answer);
}
}