Database Error Test Conection

HI,

i ' ve got IntelliJ IDEA 2016 with Mac and Java 1.8.

I try to create a simple database like this tutorial:: https://youtu.be/48FhwYB9WL8  .

For that i use mysql and download dependencies lib, then I try to test the connection.

after this I got this->

Error: Connection to aa - crm@localhost failed. Communications link failure. The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.

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This Error appears after every test with every database!!

Please can you help me.

Cheers Jim