/**
 * Usage
 */

Test t = Test.create()
             .withMember(42)
             .withString("hello")
             .withString("world")
             .build();

/**
 * Implementation
 */
public class Test {

    private final int member;
    private final List<String> strings;

    public static Test.Builder create() {
        return new Test.Builder();
    }

    private Test(Test.Builder builder) {
        this.member = builder.member;
        this.strings = builder.strings;
    }


    /*
     * ...
     * methods/getters
     * ...
     */

    private static class Builder {
        int member;
        List<String> strings;


        public Builder() {
            strings = new ArrayList<>();
        }

        public Builder withMember(int m) {
            this.member = m;
            return this;
        }

        public Builder withString(String s) {
            this.strings.add(s);
            return this;
        }

        public Test build() {
            return new Test(this);
        }
    }
}