Spring boot and java 8: Is there a way to build a string dynamically?

Is there a way to dynamically build a string in java 8 and/or spring boot? I'm trying to build an URL with parameters received from a REST Service call, this service has multiple optional filters, I can use the pseudo-AI method where I validate everything with multiple if-else but I don't think that's the best way to do it. This URL is a called to Jira REST Api so the syntax is something unique.

What I want to avoid is this

and = "\"%20AND%20\"";    
if (param1 != null) url += param1;
if (param1 != null && param2 != null) url += param1 + and + param2;
if (param1 != null && param2 != null && param3 != null) url += param1 + and + param2 + and + param3;
if (param1 != null && param2 == null && param3 != null) url += param1 + and + param3;

I think there must be a better way to do this than validating 10 times each parameter.

There are various solutions available:

• just use a StringBuilder or simple string concatenation to build up your query string
• Springs UriComponentsBuilder JavaDoc provides a more structured way of building a query string and might be more familiar to your JPA based solution
• using RestTemplates allows to pass a conditionally filled Map representing your request parameters
• Springs newer WebClient class also supports setting paramters on a get using a uri builder like this:

WebClient c = WebClient.create();
c.get().uri(uriBuilder -> uriBuilder
    .queryParam("param1", "value")
    .queryParam("param2", "value2")
    .build()
).retrieve();