Java 到 Jackson JSON 序列化:Money 字段 [英] Java to Jackson JSON serialization: Money fields

问题描述

目前，我使用 Jackson 从基于 Spring 的 Web 应用程序发送 JSON 结果.

Currently, I'm using Jackson to send out JSON results from my Spring-based web application.

我遇到的问题是试图让所有货币字段以 2 位小数输出.我无法使用 setScale(2) 解决这个问题，因为像 25.50 这样的数字被截断为 25.5 等

The problem I'm having is trying to get all money fields to output with 2 decimal places. I wasn't able to solve this problem using setScale(2), as numbers like 25.50 are truncated to 25.5 etc

有没有其他人处理过这个问题?我正在考虑使用自定义 Jackson 序列化程序制作 Money 类……您能为字段变量制作自定义序列化程序吗?您可能可以...但即便如此，我如何才能让我的客户序列化程序将该数字添加为带有 2 个小数位的数字?

Has anyone else dealt with this problem? I was thinking about making a Money class with a custom Jackson serializer... can you make a custom serializer for a field variable? You probably can... But even still, how could I get my customer serializer to add the number as a number with 2 decimal places?

推荐答案

您可以在您的资金领域使用自定义序列化程序.这是一个使用 MoneyBean 的示例.字段 amount 使用 @JsonSerialize(using=...) 进行注释.

You can use a custom serializer at your money field. Here's an example with a MoneyBean. The field amount gets annotated with @JsonSerialize(using=...).

public class MoneyBean {
    //...

    @JsonProperty("amountOfMoney")
    @JsonSerialize(using = MoneySerializer.class)
    private BigDecimal amount;

    //getters/setters...
}

public class MoneySerializer extends JsonSerializer<BigDecimal> {
    @Override
    public void serialize(BigDecimal value, JsonGenerator jgen, SerializerProvider provider) throws IOException,
            JsonProcessingException {
        // put your desired money style here
        jgen.writeString(value.setScale(2, BigDecimal.ROUND_HALF_UP).toString());
    }
}

就是这样.BigDecimal 现在以正确的方式打印.我使用了一个简单的测试用例来展示它:

That's it. A BigDecimal is now printed in the right way. I used a simple testcase to show it:

@Test
public void jsonSerializationTest() throws Exception {
     MoneyBean m = new MoneyBean();
     m.setAmount(new BigDecimal("20.3"));

     ObjectMapper mapper = new ObjectMapper();
     assertEquals("{"amountOfMoney":"20.30"}", mapper.writeValueAsString(m));
}

这篇关于Java 到 Jackson JSON 序列化:Money 字段的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！