复杂JSON字符串转换为Java嵌套对象的实现

目录

• 背景
• 方法
• 预备工作
• 构建对象模型
• 使用jackson 库解析
• 使用GSON解析
• 不含列表的嵌套对象

public static String readFromSource(String filename) {
    try {
      InputStream is = RWTool.class.getResourceAsStream(filename);
      byte[] bytes = new byte[4096];
      int num = 0;
      String json = "";
      while((num=is.read(bytes))>0){
        json=new String(bytes,0,num);
      }
      return json;
    } catch (Exception ex) {
      throw new RuntimeException(ex.getCause());
    }
}

@Getter
@Setter
public class AgentDetectEventData {
    @SerializedName("rule_id")
    @JsonProperty("rule_id")
    private String ruleId;
    @SerializedName("format_output")
    @JsonProperty("format_output")
    private String formatOutput;
    @SerializedName("info")
    @JsonProperty("info")
    private AgentDetectEventDetail info;
}
@Getter
@Setter
public class AgentDetectEventDetail {
    @SerializedName("process_events")
    @JsonProperty("process_events")
    private ProcessEvent processEvent;
    @SerializedName("proc_trees")
    @JsonProperty("proc_trees")
    private List procTree;
    @SerializedName("containers")
    @JsonProperty("containers")
    private Container container;
    @SerializedName("sockets")
    @JsonProperty("sockets")
    private Socket socket;
}
@Getter
@Setter
public class ProcessEvent {
    @SerializedName("pid")
    @JsonProperty("pid")
    private String pid;
    @SerializedName("pname")
    @JsonProperty("pname")
    private String pname;
    @SerializedName("cmdline")
    @JsonProperty("cmdline")
    private String cmdline;
    @SerializedName("ppid")
    @JsonProperty("ppid")
    private String ppid;
    @SerializedName("ppname")
    @JsonProperty("ppname")
    private String ppname;
}
@Getter
@Setter
public class ProcessTree {
    @SerializedName("pid")
    @JsonProperty("pid")
    private String pid;
    @SerializedName("pname")
    @JsonProperty("pname")
    private String pname;
    @SerializedName("cmdline")
    @JsonProperty("cmdline")
    private String cmdline;
    @SerializedName("ppid")
    @JsonProperty("ppid")
    private String ppid;
    @SerializedName("ppname")
    @JsonProperty("ppname")
    private String ppname;
}
@Getter
@Setter
public class Container {
    @SerializedName("container_id")
    @JsonProperty("container_id")
    private String containerId;
    @SerializedName("container_name")
    @JsonProperty("container_name")
    private String containerName;
    @SerializedName("image_id")
    @JsonProperty("image_id")
    private String imageId;
    @SerializedName("status")
    @JsonProperty("status")
    private String status;
}
@Getter
@Setter
public class Socket {
    @SerializedName("src_ip")
    @JsonProperty("src_ip")
    private String srcIp;
    @SerializedName("src_port")
    @JsonProperty("src_port")
    private String srcPort;
    @SerializedName("type")
    @JsonProperty("type")
    private String type;
    @SerializedName("in_out")
    @JsonProperty("in_out")
    private String inOut;
    @SerializedName("dest_ip")
    @JsonProperty("dest_ip")
    private String destIp;
    @SerializedName("dest_port")
    @JsonProperty("dest_port")
    private String destPort;
}

public class JsonUtil {
  private static Logger logger = LoggerFactory.getLogger(JsonUtil.class);
  private static final ObjectMapper MAPPER = new ObjectMapper();
  static {
    // 为保持对象版本兼容性,忽略未知的属性
    MAPPER.configure(DeserializationConfig.Feature.FAIL_ON_UNKNOWN_PROPERTIES, false);
    // 序列化的时候，跳过null值
    MAPPER.getSerializationConfig().setSerializationInclusion(JsonSerialize.Inclusion.NON_NULL);
    // date类型转化
    SimpleDateFormat fmt = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
    MAPPER.setDateFormat(fmt);
  }
  /**
   * 将一个json字符串解码为java对象
   *
   * 注意：如果传入的字符串为null，那么返回的对象也为null
   *
   * @param json json字符串
   * @param cls  对象类型
   * @return 解析后的java对象
   * @throws RuntimeException 若解析json过程中发生了异常
   */
  public static  T toObject(String json, Class cls) {
    if (json == null) {
      return null;
    }
    try {
      return MAPPER.readValue(json, cls);
    } catch (Exception e) {
      throw new RuntimeException(e.getCause());
    }
  }
  public static  String objectToJson(T obj){
    if(obj == null){
      return null;
    }
    try {
      return obj instanceof String &＃63; (String) obj : MAPPER.writeValueAsString(obj);
    } catch (Exception e) {
      return null;
    }
  }
  public static  T jsonToObject(String src, TypeReference typeReference){
    if(StringUtils.isEmpty(src) || typeReference == null){
      return null;
    }
    try {
      return (T)(typeReference.getType().equals(String.class) &＃63; src : MAPPER.readValue(src, typeReference));
    } catch (Exception e) {
      logger.warn("Parse Json to Object error",e);
      throw new RuntimeException(e.getCause());
    }
  }
  public static  T jsonToObject(String src, Class<&＃63;> collectionClass,Class<&＃63;>... elementClasses){
    JavaType javaType = MAPPER.getTypeFactory().constructParametricType(collectionClass,elementClasses);
    try {
      return MAPPER.readValue(src, javaType);
    } catch (Exception e) {
      logger.warn("Parse Json to Object error",e);
      throw new RuntimeException(e.getCause());
    }
  }
}

public class JsonUtilTest {
    @Test
    public void testParseJson() {
        String json = RWTool.readFromSource("/json.txt");
        List ade = JsonUtil.jsonToObject(json, new TypeReference>() {});
        Assert.assertNotNull(ade);
    }
    @Test
    public void testParseJson2() {
        String json = RWTool.readFromSource("/json.txt");
        List ade = JsonUtil.jsonToObject(json, List.class, AgentDetectEventData.class);
        Assert.assertNotNull(ade);
    }
}

       org.codehaus.jackson
       jackson-mapper-asl
       1.9.4

public class GsonUtil {
  static GsonBuilder gsOnBuilder= null;
  static {
    gsOnBuilder= new GsonBuilder();
    gsonBuilder.setDateFormat("yyyy-MM-dd HH:mm:ss");
  }
  public static Gson getGson() {
    return gsonBuilder.create();
  }
  public static  T fromJson(String json, Class cls) {
    return getGson().fromJson(json, cls);
  }
  public static  T fromJson(String json, Type type) {
    return getGson().fromJson(json, type);
  }
}

public class GsonUtilTest {
    @Test
    public void testParseJson() {
        String json = RWTool.readFromSource("/json.txt");
        List ade = GsonUtil.fromJson(json, new TypeToken>(){}.getType());
        Assert.assertNotNull(ade);
    }
}

       com.google.code.gson
       gson
       2.3.1

@Test
public void testParseSimpleNestedJson() {
    String json = "{"goods":{"desc":"2箱*250g","goodsId":8866,"orderNo":"E20210522120237009258","shopId":659494,"title":"认养一头牛"},"order":{"bookTime":1621656157,"codPay":false,"deliveryType":"express","orderNo":"E20210522120237009258","shopId":659494,"userId":1476}}";
    BookInfo bookInfo = JsonUtil.toObject(json, BookInfo.class);
    Assert.assertNotNull(bookInfo);
}
@Test
public void testParseSimpleNestedJson() {
    String json = "{"goods":{"desc":"2箱*250g","goodsId":8866,"orderNo":"E20210522120237009258","shopId":659494,"title":"认养一头牛"},"order":{"bookTime":1621656157,"codPay":false,"deliveryType":"express","orderNo":"E20210522120237009258","shopId":659494,"userId":1476}}";
    BookInfo bookInfo = GsonUtil.fromJson(json, BookInfo.class);
    Assert.assertNotNull(bookInfo);
}