使用gson和fastjson来解析json

自己开发过程中使用gson和fastjson来解析json的一点总结。

一、使用谷歌的gson和阿里巴巴的fastjson都能够很好地实现json和java对象的互相转换，只是所引用的jar库不同，具体使用方法也不同。

　　(1)gson需要引用google的的jar，比如gson-2.3.jar（http://maven.outofmemory.cn/com.google.code.gson/gson/2.3/）

　　(2)fastjson需要引用alibaba的jar，比如fastjson-1.2.28.jar（http://mvnrepository.com/artifact/com.alibaba/fastjson/1.2.28）

二、测试代码

  注：两种方法使用时，对象模型字段注解有差别

 (1)测试main方法

package mytest;
import java.lang.reflect.Type;
import java.util.List;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;
import com.google.gson.Gson;
import com.google.gson.reflect.TypeToken;

import mytest.model.GsonModelP;
import mytest.model.ModelP;

/**
 * json - java 转换
 * 
 * @author Administrator
 * @time 2018-09-06
 */
public class JsonParse {
    public static void main(String[] args) {
        //1、json字符串数组转java对象集合
        String arrayJson = "[{"
                + "\"layerId\":" + "0"
                + ",\"layerName\":"+ "\"SIP_BDC_QJ.dbo.BDC_ZD工业地块\""
                + ",\"displayFieldName\":"+ "\"YSDM\""
                + ",\"value\":"+ "\"73\""
                + ",\"attributes\":"
                + "{"
                + "\"地块号\":"+ "\"23066\""
                + ",\"ID\":"+ "\"73\""
                + ",\"ZDMJ\":"+ "\"20063.45\""
                + ",\"QLRMC\":"+ "\"ABC科技有限公司\""
                + ",\"SHAPE.STLength()\":"+ "\"625.749399\""
                + "}"
                + "}]";
        
        //(1.1)阿里巴巴JSON
        List<ModelP> modelPList = JSON.parseArray(arrayJson, ModelP.class);
        System.out.println("array JSON:" + modelPList.get(0).toString());
        
        //(1.2)谷歌GSON
        Type type = new TypeToken<List<GsonModelP>>(){}.getType(); //复杂对象，定义转换类型
        List<GsonModelP> modelPList2 = new Gson().fromJson(arrayJson, type);
        System.out.println("array GSON:" + modelPList2.get(0));
        
        
        //2、json字符串转java对象
        String strJson = "{"
                + "\"layerId\":" + "0"
                + ",\"layerName\":"+ "\"SIP_BDC_QJ.dbo.BDC_ZD工业宗地\""
                + ",\"displayFieldName\":"+ "\"YSDM\""
                + ",\"value\":"+ "\"73\""
                + ",\"attributes\":"
                + "{"
                + "\"宗地号\":"+ "\"23066\""
                + ",\"ID\":"+ "\"73\""
                + ",\"ZDMJ\":"+ "\"20063.45\""
                + ",\"QLRMC\":"+ "\"苏州晶能科技有限公司\""
                + ",\"SHAPE.STLength()\":"+ "\"625.749399\""
                + "}"
                + "}";
        
        //(2.1)阿里巴巴JSON
        JSONObject jsonObj = JSON.parseObject(strJson);
        ModelP modelP = jsonObj.toJavaObject(ModelP.class);
        System.out.println("str JSON:" + modelP.toString());
        
        //(2.2)谷歌GSON
        GsonModelP modelP2 = new Gson().fromJson(strJson, GsonModelP.class);
        System.out.println("str GSON:" + modelP2.toString());
        
        
        //3、java对象转json字符串
        //(3.1)阿里巴巴JSON
        String javaObjToJsonStr = JSON.toJSON(modelP).toString();
        System.out.println("java obj to JSON:" + javaObjToJsonStr);
        
        //(3.2)谷歌GSON
        String javaToJson = new Gson().toJson(modelP2);
        System.out.println("java obj to GSON:" + javaToJson);
    }

}

(2)测试model

package mytest.model;

public class ModelP {
    private String layerId;
    private String layerName;
    private String displayFieldName;
    private String value;
    private ModelC attributes;
    
    public String getLayerId() {
        return layerId;
    }
    public void setLayerId(String layerId) {
        this.layerId = layerId;
    }
    public String getLayerName() {
        return layerName;
    }
    public void setLayerName(String layerName) {
        this.layerName = layerName;
    }
    public String getDisplayFieldName() {
        return displayFieldName;
    }
    public void setDisplayFieldName(String displayFieldName) {
        this.displayFieldName = displayFieldName;
    }
    public String getValue() {
        return value;
    }
    public void setValue(String value) {
        this.value = value;
    }
    public ModelC getAttributes() {
        return attributes;
    }
    public void setAttributes(ModelC attributes) {
        this.attributes = attributes;
    }
    @Override
    public String toString() {
        return "ModelP ["
                + "layerId=" + layerId
                + ", layerName=" + layerName
                + ", displayFieldName=" + displayFieldName
                + ", value=" + value
                + ", attributes ["
                + "ID =" + attributes.getID()
                + ", landID =" + attributes.getLandID()
                + ", landArea =" + attributes.getLandArea()
                + ", obliName =" + attributes.getObliName()
                + "]"
                + "]";
    }

}

package mytest.model;
import com.alibaba.fastjson.annotation.JSONField;

public class ModelC {

    private String ID;
    
    @JSONField(name = "地块号")
    private String landID;
    
    @JSONField(name = "ZDMJ")
    private String landArea;
    
    @JSONField(name = "QLRMC")
    private String obliName;
    
    public String getID() {
        return ID;
    }
    public void setID(String iD) {
        ID = iD;
    }
    public String getLandID() {
        return landID;
    }
    public void setLandID(String landID) {
        this.landID = landID;
    }
    public String getLandArea() {
        return landArea;
    }
    public void setLandArea(String landArea) {
        this.landArea = landArea;
    }
    public String getObliName() {
        return obliName;
    }
    public void setObliName(String obliName) {
        this.obliName = obliName;
    }
    
}

package mytest.model;

public class GsonModelP {
    private String layerId;
    private String layerName;
    private String displayFieldName;
    private String value;
    private GsonModelC attributes;
    
    public String getLayerId() {
        return layerId;
    }
    public void setLayerId(String layerId) {
        this.layerId = layerId;
    }
    public String getLayerName() {
        return layerName;
    }
    public void setLayerName(String layerName) {
        this.layerName = layerName;
    }
    public String getDisplayFieldName() {
        return displayFieldName;
    }
    public void setDisplayFieldName(String displayFieldName) {
        this.displayFieldName = displayFieldName;
    }
    public String getValue() {
        return value;
    }
    public void setValue(String value) {
        this.value = value;
    }
    public GsonModelC getAttributes() {
        return attributes;
    }
    public void setAttributes(GsonModelC attributes) {
        this.attributes = attributes;
    }
    @Override
    public String toString() {
        return "ModelP ["
                + "layerId=" + layerId
                + ", layerName=" + layerName
                + ", displayFieldName=" + displayFieldName
                + ", value=" + value
                + ", attributes ["
                + "ID =" + attributes.getID()
                + ", landID =" + attributes.getLandID()
                + ", landArea =" + attributes.getLandArea()
                + ", obliName =" + attributes.getObliName()
                + "]"
                + "]";
    }

}

package mytest.model;
import com.google.gson.annotations.SerializedName;

public class GsonModelC {

    private String ID;
    
    @SerializedName("地块号")
    private String landID;
    
    @SerializedName("ZDMJ")
    private String landArea;
    
    @SerializedName("QLRMC")
    private String obliName;
    
    public String getID() {
        return ID;
    }
    public void setID(String iD) {
        ID = iD;
    }
    public String getLandID() {
        return landID;
    }
    public void setLandID(String landID) {
        this.landID = landID;
    }
    public String getLandArea() {
        return landArea;
    }
    public void setLandArea(String landArea) {
        this.landArea = landArea;
    }
    public String getObliName() {
        return obliName;
    }
    public void setObliName(String obliName) {
        this.obliName = obliName;
    }
    
}