JDBC学习--封装DBUtil

SQLServerDBConnection(获取一个SqlServer连接)

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

public class SQLServerDBConnection {

	private static final String DRIVER_CLASS = "com.microsoft.sqlserver.jdbc.SQLServerDriver";
	private static final String DATABASE_URL = "jdbc:sqlserver://localhost:1433;DatabaseName=homeWork";
	private static final String DATABASE_USRE = "sa";
	private static final String DATABASE_PASSWORD = "123456";

	public static Connection getConnction() {
		Connection dbConnection = null;
		try {
			Class.forName(DRIVER_CLASS);
			dbConnection = DriverManager.getConnection(DATABASE_URL, DATABASE_USRE, DATABASE_PASSWORD);
		} catch (Exception e) {
			e.printStackTrace();
		}
		return dbConnection;
	}

	public static void closeConnection(Connection dbConnection) {
		try {
			if (dbConnection != null && (!dbConnection.isClosed())) {
				dbConnection.close();
			}
		} catch (SQLException sqlEx) {
			sqlEx.printStackTrace();
		}
	}

	public static void closeResultSet(ResultSet res) {
		try {
			if (res != null) {
				res.close();
				res = null;
			}
		} catch (SQLException e) {
			e.printStackTrace();
		}
	}

	public static void closeStatement(PreparedStatement pStatement) {
		try {
			if (pStatement != null) {
				pStatement.close();
				pStatement = null;
			}
		} catch (SQLException e) {
			e.printStackTrace();
		}
	}
}

MysqlDBConnection(获取一个Mysql连接)

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

public class MysqlDBConnection {

	private static final String DRIVER_CLASS = "com.mysql.jdbc.Driver";
	private static final String DATABASE_URL = "jdbc:mysql://localhost:3306/learn?characterEncoding=utf8&useSSL=true";
	private static final String DATABASE_USRE = "root";
	private static final String DATABASE_PASSWORD = "root";

	public static Connection getConnction() {
		Connection dbConnection = null;
		try {
			Class.forName(DRIVER_CLASS);
			dbConnection = DriverManager.getConnection(DATABASE_URL, DATABASE_USRE, DATABASE_PASSWORD);
		} catch (Exception e) {
			e.printStackTrace();
		}
		return dbConnection;
	}

	public static void closeConnection(Connection dbConnection) {
		try {
			if (dbConnection != null && (!dbConnection.isClosed())) {
				dbConnection.close();
			}
		} catch (SQLException sqlEx) {
			sqlEx.printStackTrace();
		}
	}

	public static void closeResultSet(ResultSet res) {
		try {
			if (res != null) {
				res.close();
				res = null;
			}
		} catch (SQLException e) {
			e.printStackTrace();
		}
	}

	public static void closeStatement(PreparedStatement pStatement) {
		try {
			if (pStatement != null) {
				pStatement.close();
				pStatement = null;
			}
		} catch (SQLException e) {
			e.printStackTrace();
		}
	}
}

DBUtil

package utils;

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

public class DBUtil {
	private static Connection conn;
	private static PreparedStatement pstmt;
	private static ResultSet rs;

	/**
	 * 增，删，改
	 * 
	 * @param sql
	 * @param objects
	 * @return
	 */
	public static int execute(String sql, Object... objects) {
		int count = 0;
		try {
			getMysqlConnection();
			pstmt = conn.prepareStatement(sql);
			for (int i = 0; i < objects.length; i++) {
				pstmt.setObject(i + 1, objects[i]);
			}
			count = pstmt.executeUpdate();
		} catch (SQLException e) {
			e.printStackTrace();
		} catch (Exception e) {
			e.printStackTrace();
		}
		return count;
	}

	/**
	 * 查
	 * 
	 * @param str
	 * @param objects
	 * @return
	 */
	public static ResultSet query(String str, Object... objects) {
		try {
			getMysqlConnection();
			pstmt = conn.prepareStatement(str);
			for (int i = 0; i < objects.length; i++) {
				pstmt.setObject(i + 1, objects[i]);
			}
			rs = pstmt.executeQuery();

		} catch (Exception e) {
			e.printStackTrace();
		}
		return rs;
	}

	// 获得mysql连接
	public static void getMysqlConnection() {
		conn = MysqlDBConnection.getConnction();
	}

	// 获得SqlServer连接
	public static void getSqlserverConnection() {
		conn = SQLServerDBConnection.getConnction();
	}

	// 关闭连接
	public static void close() {
		MysqlDBConnection.closeResultSet(rs);
		MysqlDBConnection.closeStatement(pstmt);
		MysqlDBConnection.closeConnection(conn);
	}
}