class ImgJsonSerializer extends JsonSerializer<String> {

	@Value("${biz.oss.resources-url}")
	private String imgDomain;

	@Override
	public void serialize(String value, JsonGenerator gen, SerializerProvider serializers) throws IOException {<FILL_FUNCTION_BODY>}
}

		if (StrUtil.isBlank(value)) {
			gen.writeString(StrUtil.EMPTY);
			return;
		} else if (StrUtil.isBlank(imgDomain)) {
			gen.writeString(value);
			return;
		}
		String[] imgs = value.split(StrUtil.COMMA);
		StringBuilder sb = new StringBuilder();

		for (String img : imgs) {
			// 图片为http协议开头，直接返回
			if (PrincipalUtil.isHttpProtocol(img)) {
				sb.append(img).append(StrUtil.COMMA);
			}
			else {
				sb.append(imgDomain).append(img).append(StrUtil.COMMA);
			}
		}
		sb.deleteCharAt(sb.length() - 1);
		gen.writeString(sb.toString());
	
<no_super_class>