以前的技術棧一直是圍繞.net 作的，如今.net 技術棧的使用愈來愈少，愈來愈窄。好多原來的同事都轉Java開發了。java
最近公司變更，本身須要從新找個坑，壓力山大。好多要求Java技術棧的根本沒機會進，本身的那點Java功底，以前作過混合開發的Java插件，Web項目10多年沒碰了...web
好在幾個原來的同事都是所在公司的骨幹，Java也用的很溜，嗯，向人家學習吧。。。spring
先把相關的傢伙事準備好。數據庫
該安裝的安裝，該配置的配置。apache
開始架構第一個項目。點菜單File->New->Project。打開New Project窗口。左邊選Spring，右邊選擇Spring MVC。瀏覽器
拉到下邊選擇Hibernate和SQL Support,數據庫支持選擇MySQLtomcat
點擊下邊Next，給項目一個名字，JavaStudy。設置項目存放目錄。設置完成後點擊下邊的按鈕Finish。而後開始自動下載所依賴的相關包。架構
很快下載完成，第一個項目基本輪廓就有了。app
選中web目錄下的index.jsp而後點擊菜單Run->run 'index.jsp'，開始第一次運行。。。jsp
[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 嚴重 [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 嚴重 [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.
第一次運行果真會掉進坑裏...。各類搜索，而後作了下邊的操做。在web->WEB-INF目錄下新建一個classes目錄。而後建一個logging.properties文件。
logging.properties文件內容以下：
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
這樣運行後控制檯就能夠顯示具體的錯誤。不然只顯示出錯，不顯示具體內容，再次運行，
嚴重: 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，這應該是沒有找到這個包。新建立的項目按道理說不該該啊。選中項目，而後按F4，打開Project Structure窗口。
在Project Settings找到了Artifacts中找到了一些問題提示。項目輸出結構貌似有問題。依賴包找不到
點擊下邊的Fix按鈕，選擇Add all missing 。。。
三個缺失的依賴庫被自動添加了
點擊OK，再次運行...，
瀏覽器打開了，這是要成功的節奏啊。期待hello world...
404是幾個意思？
又掉坑裏了...
用IDEA+Tomcat + 404作關鍵字，搜索後找到了相似的問題，
Run->Edit Configuration,打開Run/Debug Configurations，選中Tomcate Server下的index.jsp，右邊選擇Deployment選項卡，而後把Application context 下的內容改爲「/」,點擊按鈕OK
再次運行。。。
終於出來了
出現java.io.FileNotFoundException: C:\Program Files\Apache Software Foundation\Tomcat 8.5\bin\..\logs\error-debug.2019-07-25.log (拒絕訪問。)錯誤的時候是由於權限不足，沒法寫入權限，用管理員身份運行Intellij IDEA便可。或者找到寫log的配置項，把log位置配置到有權限的位置也能夠。