I am a novice in some common mistakes and solutions, and I have recorded every error I encounter.
1. 404 Error
description The requested resource (/Struts2_0100_Introduction/hello.action) is not available.
First check Manager Deployments to enable it to be opened (NullPointerException cannot be opened). The main reason is that the server backups before each time, and then cannot correct them in time after modifying the error. (If it is a checked Backup, change it to delete)
2. Error configuring application listener of class org.springframework.web.context.ContextLoaderListener
java.lang.ClassNotFoundException: org.springframework.web.context.ContextLoaderListener
The port is written incorrectly, the port is 3306, I wrote it
8080
Problem description | Problem Situation | Problem solving |
Serious: StandardServer.await: create[8005]: java.net.BindException: Address already in use: JVM_Bind |
|
|
Error configuring application listener of class org.springframework.web.context.ContextLoaderListener java.lang.ClassNotFoundException: org.springframework.web.context.ContextLoaderListener | Spring 3.0 Web Libraries package not introduced | Rebuild the project and introduce the Spring 3.0 Web Libraries package when adding the Spring package |
java.lang.ClassCastException: java.lang.Integer cannot be cast to java.util.List | Object o=session.getAttribute(a); List l = (List)o; Cannot convert object to List | It cannot be solved, I have found a lot of them, and they all say that they can be converted, but I can't use it. I will convert the object object into a String object and then put it in the list String s=session.getA...(a).toString(); List<String> l=new ArrayList(); L.add(s); |
Errors occurred during the build. Errors running builder 'DeploymentBuilder' on project 'Project name'. java.lang.NullPointerException | This problem usually occurs when Myeclipse saves files and deploys them automatically. When writing the project, before I could deploy it, I closed myeclipse 10, and this happened. There is a reason for this error because this project is not created by myeclipse, needs to check the .project file and add com.genuitec.eclipse.j2eedt.core.webnature. | 1. First close the MyEclipse workspace. 2. Then delete "/.metadata/.plugins/org.eclipse.core.runtime/.settings/com.genuitec.eclipse.ast.deploy.core.prefs" in the workspace Cancel the automatic deployment of myeclipse: Right-click on the project ->properties ->Builders, and check DeploymentBuilder to remove. |
Js file error | Select js right-click->MyEclipse->Exclude From Validation Check | |
The J2EE project in Eclipse is run in MyEclipse, and the servlet file is reported as an error | Select a place where the servlet error is reported and add a javaee.jar package to enter | |
You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'by publishDate desc limit 0,8' at line 1 | There is a problem with the injected database statement | Pay special attention to the problem of spaces in statements on both sides of "+x+" |
Clicking the deployment button is invalid | Find the working path of MyEclipse, go to "/.metadata/.plugins/org.eclipse.core.runtime/.settings" to find a .prefs file containing deploy to delete (com.genuitec.eclipse.ast.deploy.core.prefs). Restart MyEclipse and it's OK again. | |
Type Action question!list cannot be found in the namespace / | Window-->Preference-->Myeclipse->Validation->Removing the Build column checkmark after struts2 Validator confirms (If it doesn't work, you can remove all build columns, it's useless) | |
The above summary of some common Java error and exception handling methods is all the content I share with you. I hope you can give you a reference and I hope you can support Wulin.com more.