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，该配置的配置。

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。。。

[-- ::,] Artifact JavaStudy:war exploded: Artifact is being deployed, please wait...
-Jul- ::40.672 警告 [RMI TCP Connection()-127.0.0.1] org.apache.tomcat.util.descriptor.web.WebXml.setVersion Unknown version string [4.0]. Default version will be used.
-Jul- ::40.786 严重 [RMI TCP Connection()-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
-Jul- ::40.788 严重 [RMI TCP Connection()-127.0.0.1] org.apache.catalina.core.StandardContext.startInternal Context [/JavaStudy_war_exploded] startup failed due to previous errors
[-- ::,] 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:)
    at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:)
    at org.apache.catalina.core.DefaultInstanceManager.loadClass(DefaultInstanceManager.java:)
    at org.apache.catalina.core.DefaultInstanceManager.loadClassMaybePrivileged(DefaultInstanceManager.java:)
    at org.apache.catalina.core.DefaultInstanceManager.newInstance(DefaultInstanceManager.java:)
    at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:)
    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:)
    at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:)
    at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:)
    at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:)
    at org.apache.catalina.startup.HostConfig.manageApp(HostConfig.java:)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
[-- ::,] Artifact JavaStudy:war exploded: Error during artifact deployment. See server log for details.
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:)
    at java.lang.reflect.Method.invoke(Method.java:)
    at org.apache.tomcat.util.modeler.BaseModelMBean.invoke(BaseModelMBean.java:)
    at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.invoke(DefaultMBeanServerInterceptor.java:)
    at com.sun.jmx.mbeanserver.JmxMBeanServer.invoke(JmxMBeanServer.java:)
    at org.apache.catalina.mbeans.MBeanFactory.createStandardContext(MBeanFactory.java:)
    at org.apache.catalina.mbeans.MBeanFactory.createStandardContext(MBeanFactory.java:)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:)
    at java.lang.reflect.Method.invoke(Method.java:)
    at org.apache.tomcat.util.modeler.BaseModelMBean.invoke(BaseModelMBean.java:)
    at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.invoke(DefaultMBeanServerInterceptor.java:)
    at com.sun.jmx.mbeanserver.JmxMBeanServer.invoke(JmxMBeanServer.java:)
    at com.sun.jmx.remote.security.MBeanServerAccessController.invoke(MBeanServerAccessController.java:)
    at javax.management.remote.rmi.RMIConnectionImpl.doOperation(RMIConnectionImpl.java:)
    at javax.management.remote.rmi.RMIConnectionImpl.access$(RMIConnectionImpl.java:)
    at javax.management.remote.rmi.RMIConnectionImpl$PrivilegedOperation.run(RMIConnectionImpl.java:)
    at java.security.AccessController.doPrivileged(Native Method)
    at javax.management.remote.rmi.RMIConnectionImpl.doPrivilegedOperation(RMIConnectionImpl.java:)
    at javax.management.remote.rmi.RMIConnectionImpl.invoke(RMIConnectionImpl.java:)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:)
    at java.lang.reflect.Method.invoke(Method.java:)
    at sun.rmi.server.UnicastServerRef.dispatch(UnicastServerRef.java:)
    at sun.rmi.transport.Transport$.run(Transport.java:)
    at sun.rmi.transport.Transport$.run(Transport.java:)
    at java.security.AccessController.doPrivileged(Native Method)
    at sun.rmi.transport.Transport.serviceCall(Transport.java:)
    at sun.rmi.transport.tcp.TCPTransport.handleMessages(TCPTransport.java:)
    at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run0(TCPTransport.java:)
    at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.lambda$run$(TCPTransport.java:)
    at java.security.AccessController.doPrivileged(Native Method)
    at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(TCPTransport.java:)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:)
    at java.lang.Thread.run(Thread.java:)

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

出现java.io.FileNotFoundException: C:\Program Files\Apache Software Foundation\Tomcat 8.5\bin\..\logs\error-debug.2019-07-25.log (拒绝访问。)错误的时候是因为权限不足，无法写入权限，用管理员身份运行Intellij IDEA即可。或者找到写log的配置项，把log位置配置到有权限的位置也可以。