public StrBuilder(String str) { super(); if (str == null) { buffer = new char[CAPACITY]; } else { buffer = new char[str.length() + CAPACITY]; append(str); }
public StrBuilder() { this(CAPACITY);
    public StrBuilder(String str) {        super();        if (str == null) {            buffer = new char[CAPACITY];        } else {            buffer = new char[str.length() + CAPACITY];            append(str);        }    }