Maven Missing artifact jar

maven error:
Multiple annotations found at this line:
    - Missing artifact log4j:log4j:jar:1.2.15:compile
    - Missing artifact org.apache.xmlbeans:xmlbeans-xpath:jar:2.4.0:compile
    - Missing artifact org.apache.ws.commons.axiom:axiom-dom:jar:1.2.5:compile
    - Missing artifact org.apache.httpcomponents:httpcore:jar:4.0-alpha5:compile

.... and so many more ...

解决方法：

It is not a unique issue, happens every now and then (sometimes due to a slow connection and sometimes due to proxy servers now allowing to download)

You can get rid of this by either of the following ways:

1) Force Update: Right Click on the Project in Eclipse -> Maven -> Update Project On this screen select the check box Force Update for Snapshots/Releases

2) Clearing Maven Cache: If you still face a problem, go to the local repository on your system, which might be present at C:\Users\myusername\.m2\repository and delete the .cache folder and then follow step 1.

3）If still facing issues, manually go to the org/apache folder and delete everything and then follow step 1. (This will definitely solve the issue.这将一定能解决.)