Salesforce Lightning JavaScript Method calling Apex Controller Method

ExampleMethodToCallApexControllerMethod.js

exampleJavaScriptMethod : function(cmp, value1, value2) {
    var action = cmp.get("c.exampleApexControllerMethod");
    action.setParams({'param1': value1, 'param2': value2 });        
    action.setCallback(this, function(response) {
        var state =  response.getState();
        console.log('exampleJavaScriptMethod state: ' + state);
        if(cmp.isValid() && state === "SUCCESS"){
            var result = response.getReturnValue();
            console.log(result);
            // do something
        } else if (state === "ERROR"){
            var errors = response.getError();
            if (errors) 
            {
                if (errors[0] && errors[0].message) {
                    console.log(errors[0].message);
                }
            }
        }
    });

    $A.getCallback(function() {
        $A.enqueueAction(action); 
    })();
},