前提情要:

培训的时候都没讲过,也是书上看到过这么个东西,进公司干外包的第二个项目就用了这个鬼东西

自学也不是没尝试过实现,结果各种失败,还找不到问题所在,索性不写了

JNDI实现参考:

目前参考这篇博客是有效且成功的:

https://www.cnblogs.com/zhchoutai/p/7389089.html

存在的环境问题(踩过的烂坑):

1、Tomcat版本只能在8版本以下

2、MySQL驱动Jar包 只允许在5版本以下 (目前公司用的5.1版本,可能往上5.7版本也不支持了)

3、关于JNDI配置描述的正确方法(配置文件存放位置众说纷纭。。。)

实现操作:

Tomcat官方文档有描述说是有自带数据源连接池

但是没驱动,道理就是Tomcat也不知道你要连上什么厂商的数据库,Oracle? MySQL? SqlServer?

所以这东西你得自己弄

在Tomcat的Lib目录下放上这个驱动包

D:\Server\apache-tomcat-8.5.69\lib\mysql-connector-java-5.1.35.jar

然后配置连接描述:

<?xml version="1.0" encoding="UTF-8"?>
<!--
Licensed to the Apache Software Foundation (ASF) under one or more
contributor license agreements. See the NOTICE file distributed with
this work for additional information regarding copyright ownership.
The ASF licenses this file to You under the Apache License, Version 2.0
(the "License"); you may not use this file except in compliance with
the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
-->
<!-- The contents of this file will be loaded for each web application -->
<Context> <!-- Default set of monitored resources. If one of these changes, the -->
<!-- web application will be reloaded. -->
<WatchedResource>WEB-INF/web.xml</WatchedResource>
<WatchedResource>${catalina.base}/conf/web.xml</WatchedResource> <!-- Uncomment this to disable session persistence across Tomcat restarts -->
<!--
<Manager pathname="" />
--> <Resource
name="jndiTesting"
auth="Container"
type="javax.sql.DataSource"
maxActive="100"
maxIdle="30"
maxWait="10000"
username="root" password="TencentCloud@mysql5.7.18-dzz!1376"
driverClassName="com.mysql.jdbc.Driver"
url="jdbc:mysql://cdb-6cmot19i.cd.tencentcdb.com:10000/jmcwechat_cyc"/>
</Context>

注意 name,auth 这两个东西不能搞错

这个文件的位置在:

D:\Server\apache-tomcat-8.5.69\conf\context.xml

然后用IDEA随便搭建一个JavaWeb项目,就是普通项目,都不需要Maven构建的那种

在web.xml里面配置JNDI信息

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd"
version="4.0"> <resource-ref>
<description>DB Connection</description>
<res-ref-name>jndiTesting</res-ref-name>
<res-type>javax.sql.DataSource</res-type>
<res-auth>Container</res-auth>
</resource-ref>

</web-app>

文件位置(在项目里面可以找到):

C:\Users\Administrator\IdeaProjects\JndiTesting\web\WEB-INF\web.xml

检查是否连接成功:

在首页index.jsp编写 连接的嵌入代码

<%--
Created by IntelliJ IDEA.
User: Administrator
Date: 2021/7/19
Time: 18:48
To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@ page import="java.sql.*,javax.sql.*,javax.naming.*" %>

<html>
<head>
<title>$Title$</title>
</head>
<body>
$END$ <%
Connection conn = null;
try {
//初始化查找命名空间
Context ctx = new InitialContext();
//InitialContext ctx = new InitialContext();亦可
//找到DataSource,对名称进行定位java:comp/env是必须加的,后面跟你的DataSource名
DataSource ds = (DataSource)ctx.lookup("java:comp/env/jndiTesting");
//取出连接
conn = ds.getConnection();
System.out.println("connection pool connected !!");
} catch (NamingException e) {
System.out.println(e.getMessage());
} catch (SQLException e) {
e.printStackTrace();
}finally {
//注意不是关闭,是放回连接池.
conn.close();
}
%>

</body>
</html>

开启项目后,控制台成功打印:

D:\Server\apache-tomcat-8.5.69\bin\catalina.bat run
[2021-07-19 06:54:32,504] Artifact JndiTesting:war exploded: Waiting for server connection to start artifact deployment...
Using CATALINA_BASE: "C:\Users\Administrator\AppData\Local\JetBrains\IntelliJIdea2021.1\tomcat\05f72586-ccf4-4015-b51e-2d50f0d989f2"
Using CATALINA_HOME: "D:\Server\apache-tomcat-8.5.69"
Using CATALINA_TMPDIR: "D:\Server\apache-tomcat-8.5.69\temp"
Using JRE_HOME: "C:\Program Files\Java\jdk1.8.0_291"
Using CLASSPATH: "D:\Server\apache-tomcat-8.5.69\bin\bootstrap.jar;D:\Server\apache-tomcat-8.5.69\bin\tomcat-juli.jar"
Using CATALINA_OPTS: ""
19-Jul-2021 18:54:33.185 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log Server.鏈嶅姟鍣ㄧ増鏈�: Apache Tomcat/8.5.69
19-Jul-2021 18:54:33.186 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log 鏈嶅姟鍣ㄦ瀯寤�: Jun 30 2021 18:00:00 UTC
19-Jul-2021 18:54:33.186 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log 鏈嶅姟鍣ㄧ増鏈彿: 8.5.69.0
19-Jul-2021 18:54:33.186 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log 鎿嶄綔绯荤粺鍚嶇О: Windows 10
19-Jul-2021 18:54:33.186 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log OS.鐗堟湰: 10.0
19-Jul-2021 18:54:33.186 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log 鏋舵瀯: amd64
19-Jul-2021 18:54:33.186 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log Java 鐜鍙橀噺: C:\Program Files\Java\jdk1.8.0_291\jre
19-Jul-2021 18:54:33.186 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log Java铏氭嫙鏈虹増鏈�: 1.8.0_291-b10
19-Jul-2021 18:54:33.186 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log JVM.渚涘簲鍟�: Oracle Corporation
19-Jul-2021 18:54:33.186 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log CATALINA_BASE: C:\Users\Administrator\AppData\Local\JetBrains\IntelliJIdea2021.1\tomcat\05f72586-ccf4-4015-b51e-2d50f0d989f2
19-Jul-2021 18:54:33.187 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log CATALINA_HOME: D:\Server\apache-tomcat-8.5.69
19-Jul-2021 18:54:33.187 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log 鍛戒护琛屽弬鏁帮細 -Djava.util.logging.config.file=C:\Users\Administrator\AppData\Local\JetBrains\IntelliJIdea2021.1\tomcat\05f72586-ccf4-4015-b51e-2d50f0d989f2\conf\logging.properties
19-Jul-2021 18:54:33.187 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log 鍛戒护琛屽弬鏁帮細 -Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager
19-Jul-2021 18:54:33.187 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log 鍛戒护琛屽弬鏁帮細 -Dcom.sun.management.jmxremote=
19-Jul-2021 18:54:33.187 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log 鍛戒护琛屽弬鏁帮細 -Dcom.sun.management.jmxremote.port=1099
19-Jul-2021 18:54:33.187 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log 鍛戒护琛屽弬鏁帮細 -Dcom.sun.management.jmxremote.ssl=false
19-Jul-2021 18:54:33.187 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log 鍛戒护琛屽弬鏁帮細 -Dcom.sun.management.jmxremote.password.file=C:\Users\Administrator\AppData\Local\JetBrains\IntelliJIdea2021.1\tomcat\05f72586-ccf4-4015-b51e-2d50f0d989f2\jmxremote.password
19-Jul-2021 18:54:33.187 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log 鍛戒护琛屽弬鏁帮細 -Dcom.sun.management.jmxremote.access.file=C:\Users\Administrator\AppData\Local\JetBrains\IntelliJIdea2021.1\tomcat\05f72586-ccf4-4015-b51e-2d50f0d989f2\jmxremote.access
19-Jul-2021 18:54:33.187 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log 鍛戒护琛屽弬鏁帮細 -Djava.rmi.server.hostname=127.0.0.1
19-Jul-2021 18:54:33.187 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log 鍛戒护琛屽弬鏁帮細 -Djdk.tls.ephemeralDHKeySize=2048
19-Jul-2021 18:54:33.187 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log 鍛戒护琛屽弬鏁帮細 -Djava.protocol.handler.pkgs=org.apache.catalina.webresources
19-Jul-2021 18:54:33.187 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log 鍛戒护琛屽弬鏁帮細 -Dignore.endorsed.dirs=
19-Jul-2021 18:54:33.187 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log 鍛戒护琛屽弬鏁帮細 -Dcatalina.base=C:\Users\Administrator\AppData\Local\JetBrains\IntelliJIdea2021.1\tomcat\05f72586-ccf4-4015-b51e-2d50f0d989f2
19-Jul-2021 18:54:33.187 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log 鍛戒护琛屽弬鏁帮細 -Dcatalina.home=D:\Server\apache-tomcat-8.5.69
19-Jul-2021 18:54:33.187 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log 鍛戒护琛屽弬鏁帮細 -Djava.io.tmpdir=D:\Server\apache-tomcat-8.5.69\temp
19-Jul-2021 18:54:33.187 淇℃伅 [main] org.apache.catalina.core.AprLifecycleListener.lifecycleEvent 浣跨敤APR鐗堟湰[1.7.0]鍔犺浇浜嗗熀浜嶢PR鐨凙pache Tomcat鏈満搴揫1.2.30]銆�
19-Jul-2021 18:54:33.187 淇℃伅 [main] org.apache.catalina.core.AprLifecycleListener.lifecycleEvent APR鍔熻兘锛欼Pv6[true]銆乻endfile[true]銆乤ccept filters[false]銆乺andom[true]銆�
19-Jul-2021 18:54:33.188 淇℃伅 [main] org.apache.catalina.core.AprLifecycleListener.lifecycleEvent APR/OpenSSL閰嶇疆锛歶seAprConnector[false]锛寀seOpenSSL[true]
19-Jul-2021 18:54:33.190 淇℃伅 [main] org.apache.catalina.core.AprLifecycleListener.initializeSSL OpenSSL鎴愬姛鍒濆鍖� [OpenSSL 1.1.1k 25 Mar 2021]
19-Jul-2021 18:54:33.276 淇℃伅 [main] org.apache.coyote.AbstractProtocol.init 鍒濆鍖栧崗璁鐞嗗櫒 ["http-nio-8080"]
19-Jul-2021 18:54:33.286 淇℃伅 [main] org.apache.tomcat.util.net.NioSelectorPool.getSharedSelector Using a shared selector for servlet write/read
19-Jul-2021 18:54:33.295 淇℃伅 [main] org.apache.catalina.startup.Catalina.load Initialization processed in 315 ms
19-Jul-2021 18:54:33.318 淇℃伅 [main] org.apache.catalina.core.StandardService.startInternal 姝e湪鍚姩鏈嶅姟[Catalina]
19-Jul-2021 18:54:33.318 淇℃伅 [main] org.apache.catalina.core.StandardEngine.startInternal 姝e湪鍚姩 Servlet 寮曟搸锛歔Apache Tomcat/8.5.69]
19-Jul-2021 18:54:33.323 淇℃伅 [main] org.apache.coyote.AbstractProtocol.start 寮�濮嬪崗璁鐞嗗彞鏌刐"http-nio-8080"]
19-Jul-2021 18:54:33.330 淇℃伅 [main] org.apache.catalina.startup.Catalina.start Server startup in 34 ms
Connected to server
[2021-07-19 06:54:33,546] Artifact JndiTesting:war exploded: Artifact is being deployed, please wait...
19-Jul-2021 18:54:33.656 璀﹀憡 [RMI TCP Connection(3)-127.0.0.1] org.apache.tomcat.util.descriptor.web.WebXml.setVersion 鏈煡鐗堟湰瀛楃涓� [4.0]銆傚皢浣跨敤榛樿鐗堟湰銆�
19-Jul-2021 18:54:33.809 璀﹀憡 [RMI TCP Connection(3)-127.0.0.1] org.apache.tomcat.dbcp.dbcp2.BasicDataSourceFactory.getObjectInstance Name = jndiTesting Property maxActive is not used in DBCP2, use maxTotal instead. maxTotal default value is 8. You have set value of "100" for "maxActive" property, which is being ignored.
19-Jul-2021 18:54:33.809 璀﹀憡 [RMI TCP Connection(3)-127.0.0.1] org.apache.tomcat.dbcp.dbcp2.BasicDataSourceFactory.getObjectInstance Name = jndiTesting Property maxWait is not used in DBCP2 , use maxWaitMillis instead. maxWaitMillis default value is -1. You have set value of "10000" for "maxWait" property, which is being ignored.
19-Jul-2021 18:54:33.828 淇℃伅 [RMI TCP Connection(3)-127.0.0.1] org.apache.jasper.servlet.TldScanner.scanJars 鑷冲皯鏈変竴涓狫AR琚壂鎻忕敤浜嶵LD浣嗗皻鏈寘鍚玊LD銆� 涓烘璁板綍鍣ㄥ惎鐢ㄨ皟璇曟棩蹇楄褰曪紝浠ヨ幏鍙栧凡鎵弿浣嗘湭鍦ㄥ叾涓壘鍒癟LD鐨勫畬鏁碕AR鍒楄〃銆� 鍦ㄦ壂鎻忔湡闂磋烦杩囦笉闇�瑕佺殑JAR鍙互缂╃煭鍚姩鏃堕棿鍜孞SP缂栬瘧鏃堕棿銆�
[2021-07-19 06:54:33,856] Artifact JndiTesting:war exploded: Artifact is deployed successfully
[2021-07-19 06:54:33,856] Artifact JndiTesting:war exploded: Deploy took 310 milliseconds
connection pool connected !!
connection pool connected !!
connection pool connected !!
19-Jul-2021 18:54:43.329 淇℃伅 [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory 鎶妛eb 搴旂敤绋嬪簭閮ㄧ讲鍒扮洰褰� [D:\Server\apache-tomcat-8.5.69\webapps\manager]
19-Jul-2021 18:54:43.402 璀﹀憡 [localhost-startStop-1] org.apache.tomcat.dbcp.dbcp2.BasicDataSourceFactory.getObjectInstance Name = jndiTesting Property maxActive is not used in DBCP2, use maxTotal instead. maxTotal default value is 8. You have set value of "100" for "maxActive" property, which is being ignored.
19-Jul-2021 18:54:43.402 璀﹀憡 [localhost-startStop-1] org.apache.tomcat.dbcp.dbcp2.BasicDataSourceFactory.getObjectInstance Name = jndiTesting Property maxWait is not used in DBCP2 , use maxWaitMillis instead. maxWaitMillis default value is -1. You have set value of "10000" for "maxWait" property, which is being ignored.
19-Jul-2021 18:54:43.404 淇℃伅 [localhost-startStop-1] org.apache.jasper.servlet.TldScanner.scanJars 鑷冲皯鏈変竴涓狫AR琚壂鎻忕敤浜嶵LD浣嗗皻鏈寘鍚玊LD銆� 涓烘璁板綍鍣ㄥ惎鐢ㄨ皟璇曟棩蹇楄褰曪紝浠ヨ幏鍙栧凡鎵弿浣嗘湭鍦ㄥ叾涓壘鍒癟LD鐨勫畬鏁碕AR鍒楄〃銆� 鍦ㄦ壂鎻忔湡闂磋烦杩囦笉闇�瑕佺殑JAR鍙互缂╃煭鍚姩鏃堕棿鍜孞SP缂栬瘧鏃堕棿銆�
19-Jul-2021 18:54:43.409 淇℃伅 [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Web搴旂敤绋嬪簭鐩綍[D:\Server\apache-tomcat-8.5.69\webapps\manager]鐨勯儴缃插凡鍦╗79]姣鍐呭畬鎴�

不放心还写了个Servlet查询测试了下,没问题的

package cn.dzz.util;

import javax.naming.Context;
import javax.naming.InitialContext;
import javax.naming.NamingException;
import javax.sql.DataSource;
import java.sql.Connection;
import java.sql.SQLException; public class JndiUtil { private JndiUtil(){} private static DataSource dataSource; static {
try {
Context ctx = new InitialContext();
Object lookup = ctx.lookup("java:comp/env/jndiTesting");
dataSource = (DataSource) lookup;
} catch (NamingException e) {
e.printStackTrace();
}
} public static Connection getConnection() {
try {
return dataSource.getConnection();
} catch (SQLException throwables) {
throwables.printStackTrace();
return null;
}
}
}

HelloServlet,这个是web.xml的4.0协议,可以直接写注解处理了

package cn.dzz.servlet;

import cn.dzz.util.JndiUtil;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.sql.*;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Map; @WebServlet("/hello")
public class HelloServlet extends HttpServlet { @Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
Connection connection = JndiUtil.getConnection();
try {
PreparedStatement preparedStatement = connection.prepareStatement("SELECT * FROM tt_wechat_org"); ResultSet resultSet = preparedStatement.executeQuery(); ResultSetMetaData metaData = resultSet.getMetaData(); int columnCount = metaData.getColumnCount(); // 元数据对象获取总共的记录的列数 ArrayList<Object> objects = new ArrayList<>();
while (resultSet.next()){ // 判断是否还有下一个记录行
Map<Integer,Object> map = new HashMap<Integer, Object>(); //作为每一行的记录 for (int i = 0; i < columnCount ; i++) { // 通过遍历记录列数,获取每个列的值
Object object = resultSet.getObject(i + 1);
map.put(i,object); // 装入每个字段的值
}
objects.add(map); // 遍历多少,装载多少个记录
}
resultSet.close(); // 资源释放 System.out.println(objects);
} catch (SQLException throwables) {
throwables.printStackTrace();
}
}
}

题外话:

这是简单的基础JNDI连接方式

在项目里面Spring框架还做了JNDI的支持

【Java】JNDI实现的更多相关文章

  1. Java JNDI 学习

    一.概念: 1.JNDI(JavaNaming and Directory Interface,Java命名和目录接口)是SUN公司提供的一种标准的Java命名系统接口,JNDI提供统一的客户端API ...

  2. Java JNDI Datasource HOW-TO Problem

    在开发JAVA的时候发生了点问题,解决方案记录一下,在这里http://tomcat.apache.org/tomcat-7.0-doc/jndi-datasource-examples-howto. ...

  3. Java Naming and Directory Interface (JNDI) Java 命名和目录接口

    https://www.oracle.com/technetwork/java/jndi/index.html Lesson: Overview of JNDI (The Java™ Tutorial ...

  4. Java之JNDI注入

    Java之JNDI注入 About JNDI 0x01 简介 JNDI(Java Naming and Directory Interface)是SUN公司提供的一种标准的Java命名系统接口,JND ...

  5. 用JAVA 查询 Active Directory(AD)

    Required Details LDAP address (For e.g.: myjeeva.com or IP of the Domain Controller/Global Catalog[G ...

  6. JNDI support differences between Tibco EMS and ActiveMQ

    Introduction Recently our team was working on Veracity Quick Start sprint, when I was trying to migr ...

  7. java语言体系的技术简介之JSP、Servlet、JDBC、JavaBean(Application)

    转自:https://zhangkunnan.iteye.com/blog/2040462 前言 Java语言 Java语言体系比较庞大,包括多个模块.从WEB项目应用角度讲有JSP.Servlet. ...

  8. JNDI With RMI

    JNDI With RMI JNDI with RMI JNDI即Java Naming and Directory Interface(JAVA命名和目录接口),jndi类似于一个索引中心,允许客户 ...

  9. 2.一个EJB的小Demo

    新建一个java普通项目即可 这里用到了Jboss,需要安装Jboss,然后进入jboss-4.2.3.GA\client目录,拷贝所有的jar包到本项目的lib下. 3个接口分别如下所示: publ ...

  10. 1.认识EJB

    什么是EJB?1. Enterprice JavaBeans(EJB)是一个用于分布式业务应用的标准服务端组件模型. . 采用EJB架构编写的应用是可伸的.事务性的.多用户安全的. . 采用EJB编写 ...

随机推荐

  1. 安装vmware17和下载红帽镜像

    安装vmware17 一.下载 1.访问vmware官网 (也可以使用这个链接https://www.vmware.com/products/workstation-pro/workstation-p ...

  2. tab切换之循环遍历

     <style>         *{             margin: 0;             padding:0;         }         ul,ol,li{ ...

  3. kvm链接克隆虚拟机迁移到openstack机器的实验

    总结 如果是完整克隆的那种虚拟机,是可以直接在openstack使用的,如果镜像格式没问题的话. 因为kvm虚拟机大部分都是链接克隆出来的镜像,不可用直接复制使用,所以需要创建新的镜像文件 创建空盘: ...

  4. 项目管理--PMBOK 读书笔记(11)【项目风险管理】

    1.风险分解结构(RBS): RBS 有两个含义,一个是资源分解结构(Resource),一个是风险分解结构(Risk). 1)技术风险 2)管理风险 3)商业风险 4)外部风险   2.核对单 核对 ...

  5. Eclipse build js卡死 Eclipse 编译太卡,耗时太长解决

    Eclipse build js卡死 Eclipse 编译太卡,耗时太长解决 问题描述:编译停止在js编译中,原来是js的问题 1.首选项-javaScript-Validator-Errors/Wa ...

  6. springboot3使用validation进行参数验证

    前言   今天学习了使用validation整合springboot进行字段的校验,体验下来感觉很不错,有了validation可以省下一大堆控制器里面的数据校验,例如前端发送了一个请求到我们后端,请 ...

  7. 无法启动 IIS Express Web 服务器.....另一个程序正在使用此文件,进程无法访问。 问题解决

    一般是由于端口被占用导致的,但是这个端口你在命令行netstat -a里 排除 如果发现被占用,那么就kill进程就可以了 如果没有发现被占用,依然无法启动,可以尝试以下方法 解决方案1: 修改iis ...

  8. anaconda里虚拟环境安装jupyter notebook

    安装jupyter notebook 打开anaconda prompt,进入虚拟环境 conda activate Pytorch_learning 下载安装jupyter notebook con ...

  9. python重拾基础第二天

    本节内容 列表.元祖操作 字符串操作 字典操作 集合操作 文件操作 字符编码与转码 三元运算&生成式&成员运算&解压法&队列堆栈&数据类型转换 1. 列表操作 ...

  10. Android Framework:如何让 App 拿到Power key 值

    Android app:如何让 App 拿到Power key 值 原文(有删改):https://blog.csdn.net/qq_37858386/article/details/10383566 ...