这貌似是个不为人知的语言技巧。我看到一般人写Java里初始化静态常量都是
public static final Map<String, String> DATA = new TreeMap<String, String>();static {
DATA.put("a", "A");
//blah blah blah }
public static final Map<String, String> DATA = new TreeMap<String, String>() {{this.put("a", "A");
//blah blah blah
}};