The error looks like this:
Failed to execute goal org.apache.maven.plugins:maven-shade-plugin:2.3:shade (default) on project <project_name>
Error creating shaded jar: <path>\target\classes (Access is denied)
Stacktrace:
Caused by: java.io.FileNotFoundException: <path>\target\classes (Access is denied)
at java.util.zip.ZipFile.open(Native Method)
at java.util.zip.ZipFile.<init>(ZipFile.java:215)
at java.util.zip.ZipFile.<init>(ZipFile.java:145)
at java.util.jar.JarFile.<init>(JarFile.java:153)
at java.util.jar.JarFile.<init>(JarFile.java:117)
at org.apache.maven.plugins.shade.DefaultShader.newJarFile(DefaultShader.java:267)
at org.apache.maven.plugins.shade.DefaultShader.shade(DefaultShader.java:100)
at org.apache.maven.plugins.shade.mojo.ShadeMojo.execute(ShadeMojo.java:471)
... 21 more
maven-shade-plugin tries to open classes folder as zip file. This happens when one of the dependencies is found on the local filesystem and not in the local maven repository. Before unpacking, the plugin should check whether target\classes is a directory or a zip file, but it doesn’t. One solution is to clean the local Maven repository from dependencies. It is located along the path:
Windows 7: | C:/Documents and Settings/<username>/.m2/repository |
Windows 10: | C:/Users/<username>/.m2/repository |
Linux: | /home/<username>/.m2/repository |
Mac: | /Users/<username>/.m2/repository |
Go to the repository folder and delete all content. After that, you need to re-import the dependencies.

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