问题描述
我正在尝试过滤嵌套对象中的字段:
class Response {
// These objects themselves can have many fields within
private final PropA a;
private final PropB b;
@JsonCreator
public Response(PropA a,PropB b) { ... }
}
我想要一个通用的“过滤器助手”来实现上述逻辑。这是我到目前为止所拥有的(遵循与 this project 类似的方法)
public class FilterHelper {
private final ObjectMapper objectMapper;
public FilterHelper(ObjectMapper objectMapper) {
this.objectMapper = objectMapper;
this.objectMapper.addMixIn(Object.class,MyFilterMixin.class);
}
@JsonFilter("myfilter")
public static class MyFilterMixin {
}
private static class MyFilter extends SimpleBeanPropertyFilter {
private final Set<String> properties;
public MyFilter(Set<String> properties) {
super();
this.properties = properties;
}
@Override
public void serializeAsField(final Object pojo,final JsonGenerator jgen,final SerializerProvider provider,final PropertyWriter writer) throws Exception {
System.out.println("************************** " + writer.getName());
if (properties.contains(writer.getName())) {
writer.serializeAsField(pojo,jgen,provider);
} else if (!jgen.canOmitFields()) {
writer.serializeAsOmittedField(pojo,provider);
}
}
}
public String filter(T obj,Set<String> fields) {
FilterProvider filterProvider = new SimpleFilterProvider().addFilter("myfilter",new MyFilter(fields));
return objectMapper.writer(filterProvider).writeValueAsString(obj);
}
}
当我使用 ?fields=one,two
作为查询参数点击此端点时,我希望从打印到控制台的行中看到该顶级 Response
对象中的每个字段,如下所示:
******************* a
******************* a1
******************* a2
******************* ..etc
******************* b
******************* b1
******************* b2
******************* ..etc
但在从端点获取 500 状态代码之前,我只看到顶级 a
和 b
字段的输出后跟错误:
com.fasterxml.jackson.databind.exc.InvalidDefinitionException: Cannot resolve PropertyFilter with id 'myfilter'; no FilterProvider configured (through reference chain: com.google.common.collect.SingletonImmutableList[0])
值得一提的是,我以某种方式进行了这项工作,但在一些我不记得的更改后它被破坏了。
解决方法
暂无找到可以解决该程序问题的有效方法,小编努力寻找整理中!
如果你已经找到好的解决方法,欢迎将解决方案带上本链接一起发送给小编。
小编邮箱:dio#foxmail.com (将#修改为@)