有效沟通问答-【官方】百战程序员_IT在线教育培训机构

"C:\Program Files\Java\jdk-13.0.2\bin\java.exe" -Dmaven.multiModuleProjectDirectory=C:\Users\yc\IdeaProjects\case\parent\controller "-Dmaven.home=D:\IntelliJ IDEA 2019.3.2\plugins\maven\lib\maven3" "-Dclassworlds.conf=D:\IntelliJ IDEA 2019.3.2\plugins\maven\lib\maven3\bin\m2.conf" "-Dmaven.ext.class.path=D:\IntelliJ IDEA 2019.3.2\plugins\maven\lib\maven-event-listener.jar" "-javaagent:D:\IntelliJ IDEA 2019.3.2\lib\idea_rt.jar=59100:D:\IntelliJ IDEA 2019.3.2\bin" -Dfile.encoding=UTF-8 -classpath "D:\IntelliJ IDEA 2019.3.2\plugins\maven\lib\maven3\boot\plexus-classworlds-2.6.0.jar" org.codehaus.classworlds.Launcher -Didea.version2019.3.2 org.apache.tomcat.maven:tomcat7-maven-plugin:2.2:run

[INFO] Scanning for projects...

[INFO]

[INFO] ------------------------< com.bjsxt:controller >------------------------

[INFO] Building controller 1.0-SNAPSHOT

[INFO] --------------------------------[ war ]---------------------------------

[INFO]

[INFO] >>> tomcat7-maven-plugin:2.2:run (default-cli) > process-classes @ controller >>>

[INFO]

[INFO] --- maven-resources-plugin:2.6:resources (default-resources) @ controller ---

[WARNING] Using platform encoding (UTF-8 actually) to copy filtered resources, i.e. build is platform dependent!

[INFO] Copying 5 resources

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[INFO]

[INFO] --- maven-compiler-plugin:3.1:compile (default-compile) @ controller ---

[INFO] Nothing to compile - all classes are up to date

[INFO]

[INFO] <<< tomcat7-maven-plugin:2.2:run (default-cli) < process-classes @ controller <<<

[INFO]

[INFO] --- tomcat7-maven-plugin:2.2:run (default-cli) @ controller ---

[INFO] Running war on http://localhost:8080/

[INFO] Creating Tomcat server configuration at C:\Users\yc\IdeaProjects\case\parent\controller\target\tomcat

[INFO] create webapp with contextPath:

7月 05, 2021 9:34:11 下午 org.apache.coyote.AbstractProtocol init

信息: Initializing ProtocolHandler ["http-bio-8080"]

7月 05, 2021 9:34:11 下午 org.apache.catalina.core.StandardService startInternal

信息: Starting service Tomcat

7月 05, 2021 9:34:11 下午 org.apache.catalina.core.StandardEngine startInternal

信息: Starting Servlet Engine: Apache Tomcat/7.0.47

7月 05, 2021 9:34:14 下午 org.apache.catalina.core.ApplicationContext log

信息: No Spring WebApplicationInitializer types detected on classpath

7月 05, 2021 9:34:14 下午 org.apache.catalina.core.ApplicationContext log

信息: Initializing Spring root WebApplicationContext

[INFO] Root WebApplicationContext: initialization started

[INFO] Root WebApplicationContext initialized in 1404 ms

7月 05, 2021 9:34:16 下午 org.apache.catalina.util.SessionIdGenerator createSecureRandom

信息: Creation of SecureRandom instance for session ID generation using [SHA1PRNG] took [359] milliseconds.

7月 05, 2021 9:34:16 下午 org.apache.catalina.core.ApplicationContext log

信息: Initializing Spring DispatcherServlet 'springmvc'

[INFO] Initializing Servlet 'springmvc'

[INFO] Completed initialization in 573 ms

7月 05, 2021 9:34:16 下午 org.apache.coyote.AbstractProtocol start

信息: Starting ProtocolHandler ["http-bio-8080"]

[WARNING] No mapping for GET /

7月 05, 2021 9:35:06 下午 org.apache.catalina.core.StandardWrapperValve invoke

严重: Servlet.service() for servlet [springmvc] in context with path [] threw exception [Request processing failed; nested exception is org.springframework.transaction.CannotCreateTransactionException: Could not open JDBC Connection for transaction; nested exception is com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure

The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.] with root cause

java.net.ConnectException: Connection timed out: connect

at java.base/sun.nio.ch.Net.connect0(Native Method)

at java.base/sun.nio.ch.Net.connect(Net.java:493)

at java.base/sun.nio.ch.Net.connect(Net.java:482)

at java.base/sun.nio.ch.NioSocketImpl.connect(NioSocketImpl.java:588)

at java.base/java.net.SocksSocketImpl.connect(SocksSocketImpl.java:339)

at java.base/java.net.Socket.connect(Socket.java:603)

at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:211)

at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:298)

at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2253)

at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2286)

at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2085)

at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:795)

at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:44)

at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)

at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)

at java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)

at java.base/java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:500)

at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:481)

at com.mysql.jdbc.Util.handleNewInstance(Util.java:404)

at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:400)

at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:327)

at java.sql/java.sql.DriverManager.getConnection(DriverManager.java:677)

at java.sql/java.sql.DriverManager.getConnection(DriverManager.java:189)

at org.springframework.jdbc.datasource.DriverManagerDataSource.getConnectionFromDriverManager(DriverManagerDataSource.java:155)

at org.springframework.jdbc.datasource.DriverManagerDataSource.getConnectionFromDriver(DriverManagerDataSource.java:146)

at org.springframework.jdbc.datasource.AbstractDriverBasedDataSource.getConnectionFromDriver(AbstractDriverBasedDataSource.java:205)

at org.springframework.jdbc.datasource.AbstractDriverBasedDataSource.getConnection(AbstractDriverBasedDataSource.java:169)

at org.springframework.jdbc.datasource.DataSourceTransactionManager.doBegin(DataSourceTransactionManager.java:263)

at org.springframework.transaction.support.AbstractPlatformTransactionManager.startTransaction(AbstractPlatformTransactionManager.java:400)

at org.springframework.transaction.support.AbstractPlatformTransactionManager.getTransaction(AbstractPlatformTransactionManager.java:373)

at org.springframework.transaction.interceptor.TransactionAspectSupport.createTransactionIfNecessary(TransactionAspectSupport.java:572)

at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:360)

at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:99)

at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)

at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:95)

at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)

at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:212)

at com.sun.proxy.$Proxy39.addUsers(Unknown Source)

at com.bjsxt.web.controller.UsersController.addUsers(UsersController.java:26)

at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)

at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)

at java.base/java.lang.reflect.Method.invoke(Method.java:567)

at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:190)

at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:138)

at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:106)

at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:879)

at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:793)

at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)

at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1040)

at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:943)

at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006)

at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:909)

at javax.servlet.http.HttpServlet.service(HttpServlet.java:647)

at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883)

at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)

at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:51)

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)

at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201)

at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119)

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)

at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)

at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)

at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)

at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)

at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)

at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953)

at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)

at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)

at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1041)

at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:603)

at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:312)

at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)

at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)

at java.base/java.lang.Thread.run(Thread.java:830)

显示我无法链接数据库。但是我任务管理器里面显示我的mySQL服务是正在运行状态。

而且我Navicat也可以正常连接数据库。这里我用的是users3表

JAVA 全系列/第八阶段：Linux入门到实战/Maven 19234楼

如果String输入的是汉字，它的排序规则是什么？

JAVA 全系列/第二阶段：JAVA 基础深化和提高/容器（旧） 19235楼

这个项目mysql版本需要6.0以上的吗？

这里报红了

我的mysql版本是5.7

JAVA 全系列/第十一阶段：智能家居项目（旧）/至尊智能家居第一天 19236楼

为什么敌方的生成一团找不大问题所在随机的写了不知道哪里出问题了

():
    .enemy_top = .enemy_speed = i (MainGame.enemyCount):
        left = random.randint()
        speed = random.randint()
        enemyTank = EnemyTank(.enemy_topleftspeed)
        .enemyList.append(enemyTank)

Python 全系列/第二阶段：Python 深入与提高/坦克大战 19237楼

怎么换行的老师，控制栏，我一按回车就是执行

JAVA 全系列/第二阶段：JAVA 基础深化和提高/网络编程（旧） 19238楼

ComputerFactory:
    __count=(name):
        .name=name

    (*args**kwargs):
        .__count==:
            .__count=.()
            .__count
    (a):
        a==:
            LianXiang()
        a==:
            HuaShuo()
        a==:
            ShenZhou()
        :
            ()
Computer:
    ():
        ()
LianXiang(Computer):
    ():
        ()
HuaShuo(Computer):
    ():
        ()
ShenZhou(Computer):
    ():
        ()
x=ComputerFactory()
(x)
y=ComputerFactory()
(y)
d1=x.shengchan()
d1.calculate()
d2=x.shengchan()
d2.calculate()
d3=x.shengchan()
d3.calculate()

老师，我的程序没有报错？我想问的是为什么y返回的是“None”

Python 全系列/第一阶段：Python入门/面向对象 19239楼

老师，在没有添加过滤器的时候，项目默认会执行index.jsp，但是当我添加了过滤器后就会默认执行登录页面，即使我再代码中对获得的URL中的index.jsp放行了，也还是不行，最后我发现在URL中根本就没有index.jsp，所以才会去执行请求转发。这是为什么？

package com.example.filter;

import com.example.pojo.Users;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;
import java.io.IOException;

@WebFilter(urlPatterns = {"*.jsp","*.do"})
public class UserLoginFilter implements Filter {
    /**
     *
     * @param filterConfig
     * @throws ServletException
     *
     * 用于实现用户登录的过滤器
     * 可以对所有得动态资源进行过滤，对静态资源进行放行，同时对用户的登录的.jsp或者.do资源进行放行
     *
     */
    @Override
    public void init(FilterConfig filterConfig) throws ServletException {

    }

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {

        /**
         * 对象的转换
         */
        HttpServletRequest request = (HttpServletRequest) servletRequest;

        StringBuffer requestURL = request.getRequestURL();

        /**
         * 对路径进行判断，如果是登录的请求，就去放行，否则，就是过滤
         */
        if (requestURL.indexOf("index.jsp") != -1 || requestURL.indexOf("UserLogin.jsp") != -1 || requestURL.indexOf("UserLogin.do") != -1) {

            filterChain.doFilter(servletRequest, servletResponse);

        } else {

            /**
             * 当走到else时，就表示，当前访问的不是这个登录的动态资源，那就要对你当前这个用户状态进行选择判断，
             * 如果，有sessionID就是登陆过的，否则，就是没有登陆过的。
             */
            HttpSession session = request.getSession();

            Users users = (Users) session.getAttribute("users");

            if (users != null) {
                /**
                 * 登录了，就进行放行
                 */
                filterChain.doFilter(servletRequest, servletResponse);
            } else {
                /**
                 * 没有登录就提示
                 */
                session.setAttribute("NotLoginMsg","您还没有登录请先进行登录...");
                request.getRequestDispatcher("UserLogin.jsp").forward(servletRequest, servletResponse);
            }

        }


    }

    @Override
    public void destroy() {

    }
}