Intellij IDEA 2019 + Java Spring MVC + Hibernate学习笔记(1)

之前的技术栈一直是围绕.net 做的，现在.net 技术栈的使用越来越少，越来越窄。好多原来的同事都转java开发了。

最近公司变动，自己需要重新找个坑，压力山大。好多要求java技术栈的根本没机会进，自己的那点java功底，之前做过混合开发的java插件，web项目10多年没碰了...

好在几个原来的同事都是所在公司的骨干，java也用的很溜，嗯，向人家学习吧。。。

先把相关的家伙事准备好。

该安装的安装，改配置的配置。

开始架构第一个项目。点菜单file->new->project。打开new project窗口。左边选spring，右边选择spring mvc。

拉到下边选择hibernate和sql support,数据库支持选择mysql

点击下边next，给项目一个名字，javastudy。设置项目存放目录。设置完成后点击下边的按钮finish。然后开始自动下载所依赖的相关包。

很快下载完成，第一个项目基本轮廓就有了。

选中web目录下的index.jsp然后点击菜单run->run 'index.jsp'，开始第一次运行。。。

[2019-07-21 12:23:40,433] artifact javastudy:war exploded: artifact is being deployed, please wait...
21-jul-2019 12:23:40.672 警告 [rmi tcp connection(2)-127.0.0.1] org.apache.tomcat.util.descriptor.web.webxml.setversion unknown version string [4.0]. default version will be used.
21-jul-2019 12:23:40.786 严重 [rmi tcp connection(2)-127.0.0.1] org.apache.catalina.core.standardcontext.startinternal one or more listeners failed to start. full details will be found in the appropriate container log file
21-jul-2019 12:23:40.788 严重 [rmi tcp connection(2)-127.0.0.1] org.apache.catalina.core.standardcontext.startinternal context [/javastudy_war_exploded] startup failed due to previous errors
[2019-07-21 12:23:40,804] artifact javastudy:war exploded: error during artifact deployment. see server log for details.

第一次运行果然会掉进坑里...。各种搜索，然后做了下边的操作。在web->web-inf目录下新建一个classes目录。然后建一个logging.properties文件。

logging.properties文件内容如下：

handlers = org.apache.juli.filehandler, java.util.logging.consolehandler    

############################################################
# handler specific properties.
# describes specific configuration info for handlers.
############################################################

org.apache.juli.filehandler.level = fine    
org.apache.juli.filehandler.directory = ../logs    
org.apache.juli.filehandler.prefix = error-debug.    

java.util.logging.consolehandler.level = fine    
java.util.logging.consolehandler.formatter = java.util.logging.simpleformatter

这样运行后控制台就可以显示具体的错误。否则只显示出错，不显示具体内容，再次运行，

严重: error configuring application listener of class [org.springframework.web.context.contextloaderlistener]
java.lang.classnotfoundexception: org.springframework.web.context.contextloaderlistener
    at org.apache.catalina.loader.webappclassloaderbase.loadclass(webappclassloaderbase.java:1360)
    at org.apache.catalina.loader.webappclassloaderbase.loadclass(webappclassloaderbase.java:1182)
    at org.apache.catalina.core.defaultinstancemanager.loadclass(defaultinstancemanager.java:546)
    at org.apache.catalina.core.defaultinstancemanager.loadclassmaybeprivileged(defaultinstancemanager.java:527)
    at org.apache.catalina.core.defaultinstancemanager.newinstance(defaultinstancemanager.java:150)
    at org.apache.catalina.core.standardcontext.listenerstart(standardcontext.java:4621)
    at org.apache.catalina.core.standardcontext.startinternal(standardcontext.java:5165)
    at org.apache.catalina.util.lifecyclebase.start(lifecyclebase.java:150)
    at org.apache.catalina.core.containerbase.addchildinternal(containerbase.java:743)
    at org.apache.catalina.core.containerbase.addchild(containerbase.java:719)
    at org.apache.catalina.core.standardhost.addchild(standardhost.java:714)
    at org.apache.catalina.startup.hostconfig.manageapp(hostconfig.java:1720)
    at sun.reflect.nativemethodaccessorimpl.invoke0(native method)
[2019-07-21 12:28:31,020] artifact javastudy:war exploded: error during artifact deployment. see server log for details.
    at sun.reflect.nativemethodaccessorimpl.invoke(nativemethodaccessorimpl.java:62)
    at sun.reflect.delegatingmethodaccessorimpl.invoke(delegatingmethodaccessorimpl.java:43)
    at java.lang.reflect.method.invoke(method.java:498)
    at org.apache.tomcat.util.modeler.basemodelmbean.invoke(basemodelmbean.java:287)
    at com.sun.jmx.interceptor.defaultmbeanserverinterceptor.invoke(defaultmbeanserverinterceptor.java:819)
    at com.sun.jmx.mbeanserver.jmxmbeanserver.invoke(jmxmbeanserver.java:801)
    at org.apache.catalina.mbeans.mbeanfactory.createstandardcontext(mbeanfactory.java:483)
    at org.apache.catalina.mbeans.mbeanfactory.createstandardcontext(mbeanfactory.java:432)
    at sun.reflect.nativemethodaccessorimpl.invoke0(native method)
    at sun.reflect.nativemethodaccessorimpl.invoke(nativemethodaccessorimpl.java:62)
    at sun.reflect.delegatingmethodaccessorimpl.invoke(delegatingmethodaccessorimpl.java:43)
    at java.lang.reflect.method.invoke(method.java:498)
    at org.apache.tomcat.util.modeler.basemodelmbean.invoke(basemodelmbean.java:287)
    at com.sun.jmx.interceptor.defaultmbeanserverinterceptor.invoke(defaultmbeanserverinterceptor.java:819)
    at com.sun.jmx.mbeanserver.jmxmbeanserver.invoke(jmxmbeanserver.java:801)
    at com.sun.jmx.remote.security.mbeanserveraccesscontroller.invoke(mbeanserveraccesscontroller.java:468)
    at javax.management.remote.rmi.rmiconnectionimpl.dooperation(rmiconnectionimpl.java:1468)
    at javax.management.remote.rmi.rmiconnectionimpl.access$300(rmiconnectionimpl.java:76)
    at javax.management.remote.rmi.rmiconnectionimpl$privilegedoperation.run(rmiconnectionimpl.java:1309)
    at java.security.accesscontroller.doprivileged(native method)
    at javax.management.remote.rmi.rmiconnectionimpl.doprivilegedoperation(rmiconnectionimpl.java:1408)
    at javax.management.remote.rmi.rmiconnectionimpl.invoke(rmiconnectionimpl.java:829)
    at sun.reflect.nativemethodaccessorimpl.invoke0(native method)
    at sun.reflect.nativemethodaccessorimpl.invoke(nativemethodaccessorimpl.java:62)
    at sun.reflect.delegatingmethodaccessorimpl.invoke(delegatingmethodaccessorimpl.java:43)
    at java.lang.reflect.method.invoke(method.java:498)
    at sun.rmi.server.unicastserverref.dispatch(unicastserverref.java:357)
    at sun.rmi.transport.transport$1.run(transport.java:200)
    at sun.rmi.transport.transport$1.run(transport.java:197)
    at java.security.accesscontroller.doprivileged(native method)
    at sun.rmi.transport.transport.servicecall(transport.java:196)
    at sun.rmi.transport.tcp.tcptransport.handlemessages(tcptransport.java:573)
    at sun.rmi.transport.tcp.tcptransport$connectionhandler.run0(tcptransport.java:834)
    at sun.rmi.transport.tcp.tcptransport$connectionhandler.lambda$run$0(tcptransport.java:688)
    at java.security.accesscontroller.doprivileged(native method)
    at sun.rmi.transport.tcp.tcptransport$connectionhandler.run(tcptransport.java:687)
    at java.util.concurrent.threadpoolexecutor.runworker(threadpoolexecutor.java:1149)
    at java.util.concurrent.threadpoolexecutor$worker.run(threadpoolexecutor.java:624)
    at java.lang.thread.run(thread.java:748)

java.lang.classnotfoundexception，这应该是没有找到这个包。新创建的项目按道理说不应该啊。选中项目，然后按f4，打开project structure窗口。
在project settings找到了artifacts中找到了一些问题提示。项目输出结构貌似有问题。依赖包找不到

点击下边的fix按钮，选择add all missing 。。。

三个缺失的依赖库被自动添加了

点击ok，再次运行...，

浏览器打开了，这是要成功的节奏啊。期待hello world...

404是几个意思？

又掉坑里了...

用idea+tomcat + 404做关键字，搜索后找到了类似的问题，

run->edit configuration,打开run/debug configurations，选中tomcate server下的index.jsp，右边选择deployment选项卡，然后把application context 下的内容改成“/”,点击按钮ok

再次运行。。。

终于出来了