java - 无法序列化 MongoDB 中的类 Java 和字符串被编码

Question

我的简单应用程序假设只是用 _id 到 user 之间的映射填充 MongoDB。我的key(_id)是JSON格式的，它的值只是一个long。

{
    "_id": {
        "a": "1B2ac",
        "b": "Windows NT 5.2; WOW64; rv:16.0 Ff/6.0"
    },
    "user": 1999129
}

我有几个问题:

问题 1:当我尝试插入时，我得到 can's serialize class...:

Caused by: java.lang.IllegalArgumentException: can't serialize class test.mongo.foo.DummyObject
    at org.bson.BSONEncoder._putObjectField(BSONEncoder.java:234)
    at org.bson.BSONEncoder.putObject(BSONEncoder.java:121)
    at org.bson.BSONEncoder.putObject(BSONEncoder.java:86)
    at com.mongodb.OutMessage.putObject(OutMessage.java:190)
    at com.mongodb.DBApiLayer$MyCollection.insert(DBApiLayer.java:253)
    at com.mongodb.DBApiLayer$MyCollection.insert(DBApiLayer.java:217)
    at com.mongodb.DBCollection.insert(DBCollection.java:102)
    at     com.test.mongo.foo.DaoImpl.insertRecords(DaoImpl.java:130)

这是我的 DummyObject 类(它实现了 Serializable):

 package test.mongo.foo;

import java.io.Serializable;

public class DummyObject implements Serializable{

    private static final long serialVersionUID = -2715467675581503964L;

    //default constructor
    public DummyObject(){

    }

    private String a;
    private String b;

    public String getA() {
        return a;
    }

    public String getB() {
        return b;
    }

    public void setA(String a) {
        this.a = a;
    }

    public void setB(String b) {
        this.b = b;
    }

}

这是我的DaoImp类

package test.mongo.foo;
public class DaoImpl extends MongoDAOImpl{

    public int insertRecords(List<DBObject> records) {
        DBCollection coll = getDBCollection();

        Exception e = null;
        try {
            WriteResult res =  coll.insert(records);
            if (res.getError() != null) {
                throw new MongoRuntimeException(res.getError());
            }
            return res.getN();
        } catch (Exception err) {
            e = err;
            throw new MongoRuntimeException(err);
        }
    }

    public static DBObject convertToDBObject(DummyObject obj, long value) {
        DBObject bdbo = new BasicDBObject();
        bdbo.put("_id",obj);
        bdbo.put("user",value);
        return bdbo;
    }
    public static void main(String [] args){
          DummyObject d = new DummyObject();
           d.setA("1B2ac");
           d.setB("Windows NT 5.2; WOW64; rv:16.0 Ff/6.0");
           long val = 1999129;
           List<DBObject> l = new ArrayList<DBObject>();
           l.add(DaoImpl.convertToDBObject(d,val));
           DaoImpl impl = new DaoImpl();
    }
}

问题 2: 为了避免上述问题，我尝试插入带有字符串到字符串映射的记录。虽然我的输入字符串(对于 _id)没有转义，DBObject 在内部转义它并最终写入 MongoDB，如下所示:

{
    "_id": {
        \"a\": \"1B2ac\",
        \"b\": \"WindowsNT5.2;WOW64;rv: 16.0Ff/6.0\"
    },
    "user": NumberLong(1999129)
}

代替

{
    "_id": {
        "a": "1B2ac",
        "b": "Windows NT 5.2; WOW64; rv:16.0 Ff/6.0"
    },
    "user": 1999129
}

关于如何解决这两个问题有什么建议吗？非常感谢任何指点。

Answer 1

没关系。在玩了一会儿之后，我找到了自己问题的答案。作为 JsonObject 插入。我将 DummyObject 转换为 JsonObject/Object(提示:Json.parse(jstr))

谢谢 马斯蒂