SQLServer数据库连接三

JNDI连接数据库（连接池）

public class DBConnection {
 public PreparedStatement pstmt = null;
 public Statement stmt = null;
 public Connection con = null;
 public ResultSet rs = null;
 public Result r = null;

 // JNDI获取数据源
 public Connection getConnection() {
  try {
   Context ctx = new InitialContext();
   DataSource ds = (DataSource) ctx.lookup("java:comp/env/jdbc/books");
   con = ds.getConnection();
  } catch (NamingException e) {
   e.printstacktrace();
  } catch (sqlException e) {
   e.printstacktrace();
  }
  return con;
 }

 // 通用查询方法
 public Result executeQuery(Connection con,String sql,Object[] params)
   throws sqlException {
  pstmt = con.prepareStatement(sql);
  for (int i = 0; i < params.length; i++) {
   pstmt.setobject(i + 1,params[i]);
  }
  rs = pstmt.executeQuery();
  r = ResultSupport.toResult(rs);
  return r;
 }

 // 通用增删改方法
 public int executeUpdate(Connection con,params[i]);
  }
  int num = pstmt.executeUpdate();
  return num;
 }

 // 关闭数据资源 public void closeAll() {  if (pstmt != null) {   try {    pstmt.close();   } catch (sqlException e) {    e.printstacktrace();   }  }  if (stmt != null) {   try {    stmt.close();   } catch (sqlException e) {    e.printstacktrace();   }  }  if (con != null) {   try {    con.close();   } catch (sqlException e) {    e.printstacktrace();   }  }  if (rs != null) {   try {    rs.close();   } catch (sqlException e) {    e.printstacktrace();   }  } }}