JSFiddle - React, Tailwind, and code Playground

JavaScript

var stringIHave = "Java$$Java$$jQuery$$Java$$jQuery$$Java$$Java$$Java$$Hibernate$$Java$$Java$$Spring$$Instagram$$jQuery$$jQuery$$";
var keywordsArr = stringIHave.split( '$$' );
keywordsArr.pop();
var occur = {};
for( var i = 0; i < keywordsArr.length; i++ ) {
    occur[ keywordsArr[ i ] ] = ( occur[ keywordsArr[ i ] ] || 0 ) + 1;
}

for( var key in occur ) {
    document.write( key + ' - ' + occur[key] + '<br/>');        
}