connect

关于HttpUrlconnection

不打扰是莪最后的温柔 提交于 2020-03-23 02:42:25
最常用的Http请求无非是get和post,get请求可以获取静态页面,也可以把参数放在URL字串后面,传递给servlet,post与get的不同之处在于post的参数不是放在URL字串里面,而是放在http请求的正文内。 在Java中可以使用HttpURLConnection发起这两种请求,了解此类,对于了解soap,和编写servlet的自动测试代码都有很大的帮助。 下面的代码简单描述了如何使用HttpURLConnection发起这两种请求,以及传递参数的方法: public class HttpInvoker { public static final String GET_URL = "http://localhost:8080/welcome1"; public static final String POST_URL = "http://localhost:8080/welcome1"; public static void readContentFromGet() throws IOException { // 拼凑get请求的URL字串,使用URLEncoder.encode对特殊和不可见字符进行编码 String getURL = GET_URL + "?username=" + URLEncoder.encode("fat man", "utf-8");

Can't connect to Mongo Cloud mongodb Database in Golang on Ubuntu

房东的猫 提交于 2020-03-20 06:03:41
问题 I have this Go Code to connect to my Mongo Cloud Database: func connectToDataBase() { ctx, cancel := context.WithTimeout(context.Background(), 20*time.Second) defer cancel() client, err := mongo.Connect(ctx, options.Client().ApplyURI(dbURL)) if err != nil { log.Fatal("Error connecting to Database: ", err.Error()) } DB = client.Database("storyfactory") } I already ran this code on a Windows machine, and it worked. Now I tried to run it on ubuntu, and I get following error: 2019/04/13 00:20:37

Can't connect to Mongo Cloud mongodb Database in Golang on Ubuntu

≡放荡痞女 提交于 2020-03-20 06:03:28
问题 I have this Go Code to connect to my Mongo Cloud Database: func connectToDataBase() { ctx, cancel := context.WithTimeout(context.Background(), 20*time.Second) defer cancel() client, err := mongo.Connect(ctx, options.Client().ApplyURI(dbURL)) if err != nil { log.Fatal("Error connecting to Database: ", err.Error()) } DB = client.Database("storyfactory") } I already ran this code on a Windows machine, and it worked. Now I tried to run it on ubuntu, and I get following error: 2019/04/13 00:20:37

react-redux中connect的装饰器用法@connect

怎甘沉沦 提交于 2020-03-18 17:20:35
3 月,跳不动了?>>>   最近在琢磨react中的一些小技巧,这篇文章记录一下在redux中用装饰器来写connect。   通常我们需要一个reducer和一个action,然后使用connect来包裹你的Component。假设你已经有一个key为main的reducer和一个action.js. 我们的App.js一般都这么写: import React from 'react' import {render} from 'react-dom' import {connect} from 'react-redux' import {bindActionCreators} from 'redux' import action from 'action.js' class App extends React.Component{ render(){ return <div>hello</div> } } function mapStateToProps(state){ return state.main } function mapDispatchToProps(dispatch){ return bindActionCreators(action,dispatch) } export default connect(mapStateToProps

面试大厂一定离不开的——ThreadLocal,它的实现原理你知道吗?

你。 提交于 2020-03-11 00:13:20
使用场景 假设我们有一个数据库连接管理类: class ConnectionManager { private static Connection connect = null; private static String url = System.getProperty("URL"); public static Connection openConnection() { if(connect == null){ try { connect = DriverManager.getConnection(url); } catch (SQLException e) { e.printStackTrace(); } } return connect; } public static void closeConnection() { if(connect!=null) { try { connect.close(); } catch (SQLException e) { e.printStackTrace(); } } } } 如果这个类被用在多线程环境内,则会存在线程安全问题,那么可以对这两个方法添加synchronized关键字进行同步处理,不过这样会大大降低程序的性能,也可以将connection变成局部变量: class ConnectionManager { private

oracle中 connect by prior 递归算法

一笑奈何 提交于 2020-03-10 17:11:14
Oracle中start with...connect by prior子句用法 connect by 是结构化查询中用到的,其基本语法是: select ... from tablename start with 条件1 connect by 条件2 where 条件3; 例: select * from table start with org_id = 'HBHqfWGWPy' connect by prior org_id = parent_id; 简单说来是将一个树状结构存储在一张表里,比如一个表中存在两个字段: org_id,parent_id那么通过表示每一条记录的parent是谁,就可以形成一个树状结构。 用上述语法的查询可以取得这棵树的所有记录。 其中: 条件1 是根结点的限定语句,当然可以放宽限定条件,以取得多个根结点,实际就是多棵树。 条件2 是连接条件,其中用PRIOR表示上一条记录,比如 CONNECT BY PRIOR org_id = parent_id就是说上一条记录的org_id 是本条记录的parent_id,即本记录的父亲是上一条记录。 条件3 是过滤条件,用于对返回的所有记录进行过滤。 简单介绍如下: 早扫描树结构表时,需要依此访问树结构的每个节点,一个节点只能访问一次,其访问的步骤如下: 第一步:从根节点开始; 第二步:访问该节点; 第三步

How to Slove MB SD C4 Cannot Access OBD2 Port

蓝咒 提交于 2020-03-04 04:04:33
When using china clone mb sd connect compact 4 Multiplexer, it could not link to the car computer, MB SD Connect C4 offered a message, saying like “check cable connection / turn ignition on”. Then tried again, clone SDconnect compact 4 multiplexer cannot access OBD2 port According to customer’s feedback that he failed to access to the diagnostic OBD port when tried to use sd connect c4 read errors code from Benz SRS system. The system prompted an error message “check cable connection/turn ignition on”. Possible Reason: The error lies on the SD Connect C4’s battery. ​Solution from Autonumen.com

How to solve MB SD C4 HTT-WIN failed to communicate

杀马特。学长 韩版系。学妹 提交于 2020-03-04 04:03:45
It is a long story... I recently got a MB SD Connect C4 clone (a low quality one by its looks) The multiplexer I got shipped with the following firmware: OS: 2.2.2 CSD: 2.03 When I tried to use the mux on this firmware in 03.2014 XENTRY, I was not able to connect to the car and kept getting errors. So I watched webmaster's SD connect videos and renamed the 3 update folders in C:\Program Files\SDconnect Toolkit and it worked! XENTRY was working well. The problem was when I was unable to get HHT-WIN to work. After reading around on forums, I saw this post (post #5) http://mhhauto.com/Thread

Difference Among Mercedes Star Diagnostic Tool MB Star C3 C4 C5 C6

那年仲夏 提交于 2020-03-04 04:03:35
Mercedes Star Diagnostic Tool newly update to MB Star C6.There are many star diangostic tool in the market.Many customer may dont know how to choose. Bellow, OBD2tool tell you the difference among MB Star C3 C4 C5 C6. Mercdeces Star Diagnosis C3 MB Star Compact 3 Star C3 Mb Star C3 is much better for the old Mercedes Benz and support truck speed limited function (other tools cannot do it). Star C3 software is 2018.12 now stop update anymore so that it cannot support SCN Coding. MB SD Connect C4 MB Star diagnosis Compact 4 MB Star C4 is the hot sell baby Mercedes diagnostic tool with low price

WiFi Version MB SD Connect 5 Star Diagnosis for Benz Cars and Trucks with UDS Chip

时光总嘲笑我的痴心妄想 提交于 2020-03-04 04:03:06
Autonumen.com launch a new design MB SD Connect Compact 5 Mercedes Benz Diagnostic and programming tool. This MB SD C5 have same function as MB SD C4, support multi-language, wireless and lan cable connection. Top 5 reasons to by new MB SD Connect 5: 1. Supported Multi-Language: English/Bulgarian/Danish/Greek/Spanish/French/Italian/Korean/Polish/Romanuan/Serbo-Croatian/ Turkish/Czech/German/Finish/Hynga rian/Japanese/Dutch/Portuguese/Russian/Swedish/Chinese 2. Support Wireless and Lan cable connection 3. With UDS Chip, support both K Line and CAN BUS Protocol, but also UDS Protocol 4. One MB