Question

我认为我在解析这个json对象时遗漏了一些东西。我收到的输出采用以下格式：

   {
  "columns" : [ "type", "relation" ],
  "data" : [ [ "SOURCE", {
    "paged_traverse" : "localhost/db/data/node/26/paged/traverse/{returnType}{?pageSize,leaseTime}",
    "outgoing_relationships" : "localhost/db/data/node/26/relationships/out",
    "data" : {
      "DATUM" : "December"
    },
    "all_typed_relationships" : "localhost/db/data/node/26/relationships/all/{-list|&|types}",
    "traverse" : "localhost/db/data/node/26/traverse/{returnType}",
    "self" : "localhost/db/data/node/26",
    "all_relationships" : "localhost/db/data/node/26/relationships/all",
    "property" : "localhost/db/data/node/26/properties/{key}",
    "outgoing_typed_relationships" : "localhost/db/data/node/26/relationships/out/{-list|&|types}",
    "properties" : "localhost/db/data/node/26/properties",
    "incoming_relationships" : "localhost/db/data/node/26/relationships/in",
    "incoming_typed_relationships" : "localhost/db/data/node/26/relationships/in/{-list|&|types}",
    "extensions" : {
    },
    "create_relationship" : "localhost/db/data/node/26/relationships"
  } ]]
}

我设法在GSON中正确地解析了最内部的部分：

public class Data
{
    private String paged;
    private String out;
    private Map<String, String> data;  
        ...
}

但是当我提供全身时，我得到以下异常：

Exception in thread "main" com.google.gson.JsonParseException: The JsonDeserializer MapTypeAdapter failed to deserialize json object
  {
      "columns" : [ "type", "relation" ],
      "data" : [ [ "SOURCE", {
        "paged" : foo/{returnType}{?pageSize,leaseTime}",
        "out" : "bar",
        "data" : {
          "DATUM" : "December"
          }
        } ], 
        [ "SOURCE", {
        "paged" : "test/{returnType}{?pageSize,leaseTime}",
        "out" : "baz",
        "data" : {
          "DATUM" : "Steve"
           }
         } 
        ]
      ] 
    }  given the type java.util.Map<java.lang.String, java.lang.String>

在 com.google.gson.JsonDeserializerExceptionWrapper.deserialize（JsonDeserializerExceptionWrapper.java:64）在 com.google.gson.JsonDeserializationVisitor.invokeCustomDeserializer（JsonDeserializationVisitor.java:92）在 com.google.gson.JsonObjectDeserializationVisitor.visitFieldUsingCustomHandler（JsonObjectDeserializationVisitor.java:117）在 com.google.gson.ReflectingFieldNavigator.visitFieldsReflectively（ReflectingFieldNavigator.java:63）在com.google.gson.ObjectNavigator.accept（ObjectNavigator.java:120）在 com.google.gson.JsonDeserializationContextDefault.fromJsonObject（JsonDeserializationContextDefault.java:76）在 com.google.gson.JsonDeserializationContextDefault.deserialize（JsonDeserializationContextDefault.java:54）在com.google.gson.Gson.fromJson（Gson.java:551）at com.google.gson.Gson.fromJson（Gson.java:498）at com.google.gson.Gson.fromJson（Gson.java:467）at com.google.gson.Gson.fromJson（Gson.java:417）at com.google.gson.Gson.fromJson（Gson.java:389）at com.skyscraper.transformer.NodeTransformer.fromGson（NodeTransformer.java:24）在com.skyscraper.query.read.Retriever.queryNode（Retriever.java:128）在com.skyscraper.query.read.Retriever.main（Retriever.java:67）引起的 by：java.lang.IllegalStateException：这不是JSON对象。在 com.google.gson.JsonElement.getAsJsonObject（JsonElement.java：83）at com.google.gson.MapTypeAdapter.deserialize（MapTypeAdapter.java:66）at com.google.gson.MapTypeAdapter.deserialize（MapTypeAdapter.java:33）at at com.google.gson.JsonDeserializerExceptionWrapper.deserialize（JsonDeserializerExceptionWrapper.java:51） ......还有14个

所以问题是如何正确解析这个json输出。如果它具有任何价值，则来自neo4j休息电话。

目前的实施：

   import java.util.ArrayList;
import java.util.List;

public class Wrapper {

    private String[] columns = new String[] { "type", "relation" };
    private List<List<Object>> f = new ArrayList<List<Object>>();

    public String[] getColumns() {
        return columns;
    }

    public void setColumns(String[] columns) {
        this.columns = columns;
    }

    public List<List<Object>> getF() {
        return f;
    }

    public void setF(List<List<Object>> f) {
        this.f = f;
    }
}


public class NodeTransformer {

    public static void main(String[] a) {

        Gson gson = new Gson();
        Wrapper w = new Wrapper();
        List<List<Object>> blah = w.getF();
        List<Object> objects = new ArrayList<Object>();
        objects.add(new DataNode());
        objects.add(new DataNode());

        blah.add(objects);
        w.setF(blah);
        System.out.println(gson.toJson(w));
    }

产量：

{
    "columns":["type","relation"],
    "f": [ [ 
        {"paged_traverse":"localhost/db/data/node/25/paged/traverse/{returnType}{?pageSize,leaseTime}",
        "outgoing_relationships":"localhost/db/data/node/25/relationships/out",
        "data":{},
        "all_typed_relationships":"localhost/db/data/node/25/relationships/all/{-list|\u0026|types}",
        "traverse":"localhost/db/data/node/25/traverse/{returnType}",
        "self":"localhost/db/data/node/25",
        "all_relationships":"localhost/db/data/node/25/relationships/all",
        "property":"localhost/db/data/node/25/properties/{key}",
        "outgoing_typed_relationships":"localhost/db/data/node/25/relationships/out/{-list|\u0026|types}",
        "properties":"localhost/db/data/node/25/properties",
        "incoming_relationships":"localhost/db/data/node/25/relationships/in",
        "incoming_typed_relationships":"localhost/db/data/node/25/relationships/in/{-list|\u0026|types}",
        "extensions":{},
        "create_relationship":"localhost/db/data/node/25/relationships"}}
        ]
    ]
}

Answer 1

尝试使用：

private List<List<Object>> f = new ArrayList<List<Object>>();

然后f.get(0).get(0)将为您提供一个“类型”字符串，而f.get(0).get(1)将为您提供JsonObject

http://google-gson.googlecode.com/svn/trunk/gson/docs/javadocs/com/google/gson/JsonObject.html

或者，在单独的列中返回您需要的关系数据，而不是整个关系图。

更新：也许你应该只使用springdata-neo4j。：）

如何使用数组数组解析json数组

1 个答案: