eclipse export war package

Right-click on the project -> properties
eclipse package war file
In the 'General' tab under 'Tomcat', check 'Is a Tomcat Project', select the startup path as webapp, (mine is WebRoot)
eclipse package war file
In the 'export to war settings' tab under 'Tomcat', enter the path and file name of the war file to be exported, OK, and return to the project 
eclipse to package the war file Right-click
on the project->tomcat project->Export to the war file sets in project properties to generate WAR package
eclipse packaged war file
packaged successfully, you can see the generated war file in the specified directory!
Eclipse packaged war file
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If you modify a single file, you can use zip, rar tools to replace the single file, no need to re-type