我創(chuàng)建了一個 Jackson Custom Deserializer 來反序列化 JSON 字符串：public class TestMapper extends StdDeserializer<Test> { public TestMapper() { this(null); } public TestMapper(Class<?> vc) { super(vc); } @Override public Test deserialize(JsonParser jsonParser, DeserializationContext deserializationContext) throws IOException {我想將“字符串參數(shù)”傳遞給我想在反序列化期間使用的反序列化方法。有沒有辦法做到這一點？我在我的代碼中調(diào)用解串器如下：new ObjectMapper().readValue(json, Test.class)測試類是：@JsonDeserialize(using = TestMapper.class)public class Test {
1 回答
揚帆大魚
TA貢獻1799條經(jīng)驗 獲得超9個贊
您需要創(chuàng)建帶有額外參數(shù)的構造函數(shù)，該參數(shù)將在反序列化期間使用：
import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.databind.DeserializationContext;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.deser.std.StdDeserializer;
import com.fasterxml.jackson.databind.module.SimpleModule;
import java.io.IOException;
public class JsonApp {
public static void main(String[] args) throws Exception {
SimpleModule customModule = new SimpleModule();
customModule.addDeserializer(Test.class, new TestMapper("Extra value!!!"));
ObjectMapper mapper = new ObjectMapper();
mapper.registerModule(customModule);
Test test = new Test();
test.setValue("Value");
String json = mapper.writeValueAsString(test);
System.out.println(json);
System.out.println(mapper.readValue(json, Test.class));
}
}
class TestMapper extends StdDeserializer<Test> {
private String extraConfig;
public TestMapper() {
this(null);
}
public TestMapper(String extraConfig) {
super(Test.class);
this.extraConfig = extraConfig;
}
@Override
public Test deserialize(JsonParser jsonParser, DeserializationContext deserializationContext) throws IOException {
Test test = new Test();
test.setValue(extraConfig);
return test;
}
}
class Test {
private String value;
public String getValue() {
return value;
}
public void setValue(String value) {
this.value = value;
}
@Override
public String toString() {
return "Test{" +
"value='" + value + '\'' +
'}';
}
}
上面的代碼打?。?/p>
{"value":"Value"}
Test{value='Extra value!!!'}
您應該始終提供給super constructor您POJO class的Test.class. 如果您需要更復雜的初始化，請查看ContextualDeserializer.
添加回答
舉報
0/150
提交
取消