java - uses unchecked or unsafe operations Exception thrown when I use ImmutableMap -

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• what causes javac issue “uses unchecked or unsafe operations” warning 7 answers
• what raw type , why shouldn't use it? 12 answers

always got blabla.java uses unchecked or unsafe operations exception when mvn compile immutablemap:

this code while using immutablemap

    private static immutablemap<string, object> hikariconfigmap = new immutablemap.builder()             .put("datasourceclassname", configurer.getstring("mysql.driver"))             .put("datasource.url", configurer.getstring("mysql.url"))             .put("datasource.user", configurer.getstring("mysql.user"))             .put("datasource.password", configurer.getstring("mysql.password"))             .build();     private static connectionprovider connectionprovider = new hikaricpconnectionprovider(hikariconfigmap); 

any guy tell me why?