当您具有 动态键时 ，可以使用
Map<K,V>。键的类型和值取决于您的需要。
最简单的方法是
Map<String,Object>。您需要
TypeReference<T>为此：
ObjectMapper mapper = new ObjectMapper();Map<String, Object> map = mapper.readValue(json, new TypeReference<Map<String, Object>>() {});假设您的密钥是 有效日期 ，则可以使用
Map<LocalDate, Object>。
需要以下依赖项：
<dependency> <groupId>com.fasterxml.jackson.datatype</groupId> <artifactId>jackson-datatype-jsr310</artifactId> <version>${jackson.version}</version></dependency>然后您可以拥有：
ObjectMapper mapper = new ObjectMapper();mapper.registerModule(new JavaTimeModule());Map<LocalDate, Object> map = mapper.readValue(json, new TypeReference<Map<LocalDate, Object>>() {});最后，您可以将动态键的值映射到Java类。让我们称之为
Foo：
public class Foo { private Integer downloads; @JsonProperty("re_downloads") private Integer reDownloads; private Integer updates; private Integer returns; @JsonProperty("net_downloads") private Integer netDownloads; private Integer promos; private String revenue; @JsonProperty("returns_amount") private String returnsAmount; @JsonProperty("edu_downloads") private Integer eduDownloads; private Integer gifts; @JsonProperty("gift_redemptions") private Integer giftRedemptions; // Default constructor, getters and setters omitted}然后您可以拥有
Map<LocalDate, Foo>：
ObjectMapper mapper = new ObjectMapper();mapper.registerModule(new JavaTimeModule());Map<LocalDate, Foo> map = mapper.readValue(json, new TypeReference<Map<LocalDate, Foo>>() {});
