biz处理dao层的事务

前言 正文

1.创建一个事物管理对象，该对象将连接对象绑定到当前线程

package bank.util;
import java.sql.Connection;
import java.sql.SQLException;

public class TransactionManager{
  private static ThreadLocal tl=new ThreadLocal();
  private Connection conn;
  public TransactionManager(){
    try {
      conn=ConnectionUtil.getConn();
    } catch (ClassNotFoundException e) {
      e.printStackTrace();
    } catch (SQLException e) {
      e.printStackTrace();
    }
    //将获得的连接对象绑定到线程
    tl.set(conn);
  }
  public static Connection getConn(){
    //从当前线程中获取绑定的连接对象
    return (Connection) tl.get();
  }
  //将连接对象的事务设置手动提交
  public void openTransaction(){
    try {
      conn.setAutoCommit(false);
    } catch (SQLException e) {
      // TODO Auto-generated catch block
      e.printStackTrace();
    }
  }
  //事务提交
  public void commitTransaction(){
    try {
      conn.commit();
      conn.close();
    } catch