我有以下类(class):
import org.codehaus.jackson.annotate.JsonIgnoreProperties;
import org.codehaus.jackson.annotate.JsonProperty;
import java.io.Serializable;
import java.util.HashMap;
@JsonIgnoreProperties(ignoreUnknown = true)
public class Theme implements Serializable {
@JsonProperty
private String themeName;
@JsonProperty
private boolean customized;
@JsonProperty
private HashMap<String, String> descriptor;
//...getters and setters for the above properties
}
当我执行以下代码时:
HashMap<String, Theme> test = new HashMap<String, Theme>();
Theme t1 = new Theme();
t1.setCustomized(false);
t1.setThemeName("theme1");
test.put("theme1", t1);
Theme t2 = new Theme();
t2.setCustomized(true);
t2.setThemeName("theme2");
t2.setDescriptor(new HashMap<String, String>());
t2.getDescriptor().put("foo", "one");
t2.getDescriptor().put("bar", "two");
test.put("theme2", t2);
String json = "";
ObjectMapper mapper = objectMapperFactory.createObjectMapper();
try {
json = mapper.writeValueAsString(test);
} catch (IOException e) {
e.printStackTrace();
}
生成的 json 字符串如下所示:
{
"theme2": {
"themeName": "theme2",
"customized": true,
"descriptor": {
"foo": "one",
"bar": "two"
}
},
"theme1": {
"themeName": "theme1",
"customized": false,
"descriptor": null
}
}
我的问题是将上面的 json 字符串反序列化回
HashMap<String, Theme>
对象。
我的反序列化代码如下所示:
HashMap<String, Themes> themes =
objectMapperFactory.createObjectMapper().readValue(json, HashMap.class);
它使用正确的键反序列化为 HashMap,但不会为值创建主题对象。我不知道在 readValue() 方法中指定什么来代替“HashMap.class”。
如有任何帮助,我们将不胜感激。
最佳答案
您应该创建特定的 Map 类型并将其提供给反序列化过程:
TypeFactory typeFactory = mapper.getTypeFactory();
MapType mapType = typeFactory.constructMapType(HashMap.class, String.class, Theme.class);
HashMap<String, Theme> map = mapper.readValue(json, mapType);
关于java - 使用 Jackson 反序列化为自定义对象的 HashMap,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/57727538/