Replace all double quotes within String

Here’s how

String details = "Hello \"world\"!";
details = details.replace("\"","\\\"");
System.out.println(details);               // Hello \"world\"!

Note that strings are immutable, thus it is not sufficient to simply do details.replace("\"","\\\""). You must reassign the variable details to the resulting string.

Using

details = details.replaceAll("\"","&quote;");

instead, results in

Hello &quote;world&quote;!