jdk.imports['java.util.Formatter'].load = async () => { const IllegalFormatException = await jdk.import('java.util.IllegalFormatException'); class Formatter { format(format, ...args) { let regex = /%[0-9\.]*[\w]/; for (let arg of args) { if (!regex.test(format)) { throw new IllegalFormatException(); } format = format.replace(regex, arg.toString()); } return format; } } jdk.java.util.Formatter = Formatter; };