java.lang.ThreadLocal类底层就是一个Map集合
集合的key是当前线程，
集合的value存放需要共享的数据

集合工具类的代码

[Java] 纯文本查看 复制代码

import java.sql.Connection;
import java.sql.SQLException;
import com.wuming.c3p0utils.C3P0Utils;
public class ConnectionMangager {
    private static  ThreadLocal<Connection> local=new ThreadLocal<>();
    public static Connection getConnection() throws SQLException{
        Connection con = local.get();
        if(con==null){
            con=C3P0Utils.getConnection();
            local.set(con);
        }
        return con;
    }
    public static void setAutoCommit() throws SQLException{
        getConnection().setAutoCommit(false);
    }
    
    public static void commit() throws SQLException{
        getConnection().commit();
        
    }
    
    public static void rollback() throws SQLException{
        getConnection().rollback();
    }
    
    public static void close(){
        try {
            getConnection().close();
            local.remove();
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
}

我来占层楼啊   

我也来了