J2EE常用工具类—Jdbc操作

package cn.org.jshuwei.j2ee.util;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.sql.Statement;

/**
* 
* Jdbc操作的工具类
* 
* @author huwei(jshuwei.org.cn)
* @since 1.0
* 
*/
public class JdbcUtil {
    static {
        try {
            Class.forName("oracle.jdbc.driver.OracleDriver");
            Class.forName("com.mysql.jdbc.Driver");
            Class.forName("com.microsoft.jdbc.sqlserver.SQLServerDriver");
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        }
    }

    /**
     * 得到Connection
     * 
     * @since 1.0
     * @param dbType
     *            数据库类型(oracle/mysql)
     * @return 返回Connection
     */
    public static Connection getConnection(String dbType) {
        String url = "";
        String user = "";
        String password = "";
        if (dbType.equals("oracle")) {
            url = "jdbc:oracle:thin:@localhost:6666:XE";
            user = "jshuwei";
            password = "123456";
        }
        if (dbType.equals("mysql")) {
            url = "jdbc:mysql://localhost:3306/test";
            user = "jshuwei";
            password = "123456";
        }
        if (dbType.equals("sqlServer")) {
            url = "jdbc:microsoft:sqlserver://localhost:1433;DatabaseName=db_test";
            user = "jshuwei";
            password = "123456";
        }
        try {
            return DriverManager.getConnection(url, user, password);
        } catch (SQLException e) {
            e.printStackTrace();
        }
        return null;
    }

    /**
     * 打印记录集对象
     * 
     * @since 1.0
     * @param rs
     *            需要打印的记录集对象
     */
    public static void printRs(ResultSet rs) {
        if (rs == null) {
            System.out.println("ResultSet is null!");
            return;
        }
        try {
            ResultSetMetaData md = rs.getMetaData();
            int cols = md.getColumnCount();
            for (int i = 1; i <= cols; i++) {
                // 列名，类型编号，类型名称
                System.out
                        .println(md.getColumnName(i) + "-->"
                                + md.getColumnType(i) + "-->"
                                + md.getColumnTypeName(i));
            }
            System.out.println("=========================================");
            while (rs.next()) {
                for (int i = 1; i <= cols; i++) {
                    System.out.println(md.getColumnName(i) + "="
                            + rs.getString(i) + "\t");
                }
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }

    /**
     * 释放资源
     * 
     * @since 1.0
     * @param rs
     *            需要释放的记录集对象
     * @param stmt
     *            需要释放的Statement对象
     * @param con
     *            需要释放的连接对象
     */
    public static void release(ResultSet rs, Statement stmt, Connection con) {
        if (rs != null)
            try {
                rs.close();
            } catch (Exception e) {
            }
        if (stmt != null)
            try {
                stmt.close();
            } catch (Exception e) {
            }
        if (con != null)
            try {
                con.close();
            } catch (Exception e) {
            }
    }

    /**
     * 释放资源
     * 
     * @since 1.0
     * @param o
     *            需要释放的对象
     */
    public static void release(Object o) {
        try {
            if (o instanceof ResultSet) {
                ((ResultSet) o).close();
            } else if (o instanceof Statement) {
                ((Statement) o).close();
            } else if (o instanceof Connection) {
                ((Connection) o).close();
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
}