There's a mistake in the project, but it's the right solution

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* Mistakes in the project but it's the right solution: Right-click the project Properties--project Facets--java to 1.8 (same as JDK version)
In the markers, delete the wrong, recompile. Build automatically before the default tick, remove the tick. Recompile, clean
*maven Download package: Java EE tools--update ERA Libraries Maven Download library: Run as--maven clean--maven Install
ADD Library Jre-system Library workspace default 1.8
Enable Maven depe...ment
@override error Resolution in *java: Cause: JDK problem, @Override is already on JDK, but does not support implementation of interface
Modify the configuration in Eclipse, select 1.8 at Windows--prefercnces--java--complier--complier compliance level, refresh the project, and recompile.
Right-click the project, Properties--java compiler--complier complionce level Select 1.8, refresh project, recompile

There's a mistake in the project, but it's the right solution