Description:

[ERROR] Failed to execute goal org.apache.maven.plugins:maven-install-plugin:2.3.1:install (default-install) on project ecommerce-web: Failed to install metadata com.app:ecommerce-web/maven-metadata.xml: Could not parse metadata .m2repository<project package>maven-metadata-local.xml: only whitespace content allowed before start tag and not u0 (position: START_DOCUMENT seen u0… @1:1) -> [Help 1]

Solution:

delete maven-metadata-local.xml in maven repository.
install the project, error will not be produced again.