마틴 파울러 Stub

class StringBuilder {

private List<String> strings = new ArrayList<String>();

public StringBuilder append(boolean a) {

strings.add(String.valueOf(a));

return this;

}

public StringBuilder append(String str) {

strings.add(str);

return this;

}

public String build() {

String total = new String("");

for (String string : strings) {

total += string;

}

return total;

}

/* public static void main(String[] args) {

StringBuilder builder = new StringBuilder();

String string = builder.append(true).append("abc").append("def").build();

}*/

}