Java compiler level does not match the version of the installed Java project facet. Issue

A Web project copied from a colleague, imported into Eclipse, appears in Java compiler level does not match the version of the installed Java Project facet issue.

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In fact, to solve is also very simple, under the Explorer, find the directory where the project, in the. Settings subdirectory, with a text editor to open the Org.eclipse.wst.common.project.facet.core.xml configuration file:

Modify the Red Draw line section to keep it consistent with the compiler version settings for the project.

To view the compiler version settings for your project, in the eclipse environment, right-click the project, tap Properties, select Java Compiler, and you can see the compiler version on the right side of the window:

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If you still get an error at this point, check to see if the JRE configuration in Tomcat is a locally installed JRE. New server, default "Workbench default JRE"

How to modify?

Such as:

Java compiler level does not match the version of the installed Java project facet. Issue