java - Jackson Json序列化: Remove Blank strings

Question

我尝试使用 Jackson 从生成的 Json 中排除所有空白字符串。

我知道我可以使用下面的注释来过滤它，但这似乎不能处理空白字符串。[只有空格的字符串]

@JsonInclude(JsonInclude.Include.NON_EMPTY) 

有办法做到这一点吗？

Answer 1

您可以使用自定义值过滤器，请尝试此操作并告诉我这是否适合您 -

@JsonInclude(value = JsonInclude.Include.CUSTOM, valueFilter = CustomFilter.class)

这是自定义过滤器 -

class CustomFilter {
    public CustomFilter() {
    }
    @Override
    public boolean equals(Object obj) {
        if(obj == null)
            return true;
        if(obj instanceof String){
            return ((String)obj).trim().isEmpty();
        }
        return false;
    }
}

<小时/>

根据自定义过滤器的 javadoc -

public static final JsonInclude.Include CUSTOM

Value that indicates that separate filter Object (specified by JsonInclude.valueFilter() for value itself, and/or JsonInclude.contentFilter() for contents of structured types) is to be used for determining inclusion criteria. Filter object's equals() method is called with value to serialize; if it returns true value is excluded (that is, filtered out); if false value is included.