封装JAVA数据库操作

感谢这位博主分享

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.sql.PreparedStatement;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

public class BaseDao {
public final static String DRIVER = "com.microsoft.sqlserver.jdbc.SQLServerDriver";
public final static String URL = "jdbc:sqlserver://localhost:1433;databaseName=boor";
public final static String USERNAME = "sa";
public final static String PASSWORD = "";

**
*
* @return 获得数据库连接
* @throws SQLException
* @throws ClassNotFoundException
*
public Connection getConn() {
Connection conn = null;
try {
Class.forName(DRIVER);
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
try {
conn = DriverManager.getConnection(URL, USERNAME, PASSWORD);
} catch (SQLException e) {
e.printStackTrace();
}
return conn;
}

**
* 关闭数据库连接
* @param conn数据库连接
* @param prsts  PreparedStatement 对象
* @param rs结果集
*
public void closeAll(Connection conn, PreparedStatement prsts, ResultSet rs) {
if (rs != null) {
try {
rs.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
if (prsts != null) {
try {
prsts.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
if (conn != null) {
try {
conn.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}

**
* 执行增、删、改SQL语句
*
* @param sql
*            sql语句
* @param param
*            值集
* @param type
*            值类型集
* @return 受影响的行数
*
public int executeUpdate(String sql, Object[] param, int[] type) {
int rows = 0;
Connection conn = this.getConn();
PreparedStatement prsts = null;
try {
prsts = conn.prepareStatement(sql);
for (int i = 1; i <= param.length; i++) {
prsts.setObject(i, param[i - 1], type[i - 1]);
}
rows = prsts.executeUpdate();
} catch (SQLException e) {
e.printStackTrace();
} finally {
this.closeAll(conn, prsts, null);
}
return rows;
}

**
* 执行查询SQL语句
*
* @param sql
*            sql语句
* @param param
*            值集
* @param type
*            值类型集
* @return 结果集
*
public List executeQuery(String sql, Object[] param, int[] type) {
ResultSet rs = null;
List list = null;
Connection conn = this.getConn();
PreparedStatement prsts = null;
try {
prsts = conn.prepareStatement(sql);
for (int i = 1; i <= param.length; i++) {
prsts.setObject(i, param[i - 1], type[i - 1]);
}
rs = prsts.executeQuery();
list = new ArrayList();
ResultSetMetaData rsm = rs.getMetaData();
Map map = null;
while (rs.next()) {
map = new HashMap();
for (int i = 1; i <= rsm.getColumnCount(); i++) {
map.put(rsm.getColumnName(i), rs.getObject(rsm.getColumnName(i)));
}
list.add(map);
}
} catch (SQLException e) {
e.printStackTrace();
}finally{
this.closeAll(conn, prsts, rs);
}
return list;
}

}