JackJson解析json的字符串格式

男娘i 2022-05-19 14:28 780阅读 0赞

从前台获取了一个xml,然后解析xml的属性的时候,其属性值是一个json的String类型.所以在解析json的时候,给出的问题是:

## 1,不管什么对象类型,根据json的构造,根据的key值,去取对应的value值; ##

## 2,将操作的json的对象,定义为对应的java对象,然后将json转换为对应的java对象.取java对象的属性值,即是处理的结果值. ##

两种不同的思路,性能和可维护性上面,个人感觉还是后者相对方便一点..贴下代码,看看...

第一种方式::

其json的直观视觉是:

![70][]

![70 1][]

package azkabanproject;
    
    import com.google.gson.Gson;
    import com.google.gson.JsonArray;
    import com.google.gson.JsonElement;
    import com.google.gson.JsonObject;
    
    public class ParseJsonString {
    
        public static void main(String[] args) {
    
            String jsonString = "{\n" +
                    "          \"sources\":[\n" +
                    "                {\n" +
                    "                    \"baseList\":{\n" +
                    "                        \"tableName\":\"trs_action_dzwl_zm1\",\n" +
                    "                        \"tableAlias\":\"50\",\n" +
                    "                        \"tableSize\":\"10000\",\n" +
                    "                        \"tableFields\":[\n" +
                    "                            {\n" +
                    "                                \"field\":\"name1\",\n" +
                    "                                \"fieldDesc\":\"名称1\",\n" +
                    "                                \"fieldInputtype\":\"0\"\n" +
                    "                            },\n" +
                    "                            {\n" +
                    "                                \"field\":\"name2\",\n" +
                    "                                \"fieldDesc\":\"名称2\",\n" +
                    "                                \"fieldInputtype\":\"1\"\n" +
                    "                            }\n" +
                    "                        ]\n" +
                    "                    },\n" +
                    "                    \"infoList\":[\n" +
                    "                        {\n" +
                    "                            \"field\":\"start_time\",\n" +
                    "                            \"fieldContent\":\"20170724000000到20170724101010\",\n" +
                    "                            \"fieldDesc\":\"创建时间\"\n" +
                    "                        },\n" +
                    "                        {\n" +
                    "                            \"field\":\"site_address\",\n" +
                    "                            \"fieldContent\":\"南苑大厦\",\n" +
                    "                            \"fieldDesc\":\"详细地址\"\n" +
                    "                        },\n" +
                    "                        {\n" +
                    "                            \"field\":\"name\",\n" +
                    "                            \"fieldContent\":\"自定义名称1\",\n" +
                    "                            \"fieldDesc\":\"名称\"\n" +
                    "                        }\n" +
                    "                    ]\n" +
                    "                },\n" +
                    "                {\n" +
                    "                    \"baseList\":{\n" +
                    "                        \"tableName\":\"trs_action_dzwl_zm1\",\n" +
                    "                        \"tableAlias\":\"50\",\n" +
                    "                        \"tableSize\":\"10000\",\n" +
                    "                        \"tableFields\":[\n" +
                    "                            {\n" +
                    "                                \"field\":\"name1\",\n" +
                    "                                \"fieldDesc\":\"名称1\",\n" +
                    "                                \"fieldInputtype\":\"0\"\n" +
                    "                            },\n" +
                    "                            {\n" +
                    "                                \"field\":\"name2\",\n" +
                    "                                \"fieldDesc\":\"名称2\",\n" +
                    "                                \"fieldInputtype\":\"1\"\n" +
                    "                            }\n" +
                    "                        ]\n" +
                    "                    },\n" +
                    "                    \"infoList\":[\n" +
                    "                        {\n" +
                    "                            \"field\":\"start_time\",\n" +
                    "                            \"fieldContent\":\"20170724000000到20170724101010\",\n" +
                    "                            \"fieldDesc\":\"创建时间\"\n" +
                    "                        },\n" +
                    "                        {\n" +
                    "                            \"field\":\"site_address\",\n" +
                    "                            \"fieldContent\":\"南苑大厦\",\n" +
                    "                            \"fieldDesc\":\"详细地址\"\n" +
                    "                        },\n" +
                    "                        {\n" +
                    "                            \"field\":\"name\",\n" +
                    "                            \"fieldContent\":\"自定义名称1\",\n" +
                    "                            \"fieldDesc\":\"名称\"\n" +
                    "                        }\n" +
                    "                    ]\n" +
                    "                }\n" +
                    "            ],\n" +
                    "        \"outFields\":[\n" +
                    "                {\n" +
                    "                    \"field\":\"name1\",\n" +
                    "                    \"fieldDesc\":\"名称1\",\n" +
                    "                    \"fieldInputtype\":\"0\"\n" +
                    "                },\n" +
                    "                {\n" +
                    "                    \"field\":\"name2\",\n" +
                    "                    \"fieldDesc\":\"名称2\",\n" +
                    "                    \"fieldInputtype\":\"1\"\n" +
                    "                }\n" +
                    "             ]\n" +
                    " }";
    
            parse(jsonString);
        }
        public static void parse(String jsonString) {
          //  String jsonString = "";
            Gson json = new Gson();
            JsonObject jsb = json.fromJson(jsonString, JsonObject.class);
            JsonArray sources = jsb.getAsJsonArray("sources");  //数组
            for (JsonElement ja : sources) {
                JsonElement jba = ja.getAsJsonObject().get("baseList");
                String tableName = jba.getAsJsonObject().get("tableName").getAsString();
                String tableAlias = jba.getAsJsonObject().get("tableAlias").getAsString();
                String tableSize = jba.getAsJsonObject().get("tableSize").getAsString();
                System.out.println(tableName+"___"+tableAlias+"___"+tableSize);
    
                JsonArray tableFields = jba.getAsJsonObject().get("tableFields").getAsJsonArray();
                for (JsonElement tableField : tableFields) {
                    String field = tableField.getAsJsonObject().get("field").getAsString();
                    String fieldDesc = tableField.getAsJsonObject().get("fieldDesc").getAsString();
                    String fieldInputtype = tableField.getAsJsonObject().get("fieldInputtype").getAsString();
                    System.out.println(field+"___"+fieldDesc+"___"+fieldInputtype);
                }
    
                JsonArray infoList = ja.getAsJsonObject().get("infoList").getAsJsonArray();
                for (JsonElement info : infoList) {
                    String field = info.getAsJsonObject().get("field").getAsString();
                    String fieldContent = info.getAsJsonObject().get("fieldContent").getAsString();
                    String fieldDesc = info.getAsJsonObject().get("fieldDesc").getAsString();
                    System.out.println(field+"___"+fieldContent+"___"+fieldDesc);
                }
    
            }
    
            JsonArray outFields = jsb.getAsJsonArray("outFields");
            for (JsonElement outField : outFields) {
    
               String field= outField.getAsJsonObject().get("field").getAsString();
               String fieldDesc=  outField.getAsJsonObject().get("fieldDesc").getAsString();
               String fieldInputtype=outField.getAsJsonObject().get("fieldInputtype").getAsString();
                System.out.println(field+"___"+fieldDesc+"___"+fieldInputtype);
            }
        }
    }

以上是第一种方式,使用的是Gson,然后根据json结构直接操作json数据类型.

第二种是:构建对象

对象JsonValue

package com.trs.idap.web.rest.util;
    
    import java.io.Serializable;
    import java.util.Arrays;
    
    /**
     * Created by Administrator on 2018/7/25.
     * 描述:
     * @author Young
     * @create 2018-07-25 17:44
     */
    public class JsonValue implements Serializable{
        private BaseInfo[] sources;
        private OutFields[] outFields;
    
        @Override
        public String toString() {
            return "JsonValue{" +
                "sources=" + Arrays.toString(sources) +
                ", outFields=" + Arrays.toString(outFields) +
                '}';
        }
    
        public OutFields[] getOutFields() {
            return outFields;
        }
    
        public void setOutFields(OutFields[] outFields) {
            this.outFields = outFields;
        }
    
        public BaseInfo[] getSources() {
            return sources;
        }
    
        public void setSources(BaseInfo[] sources) {
            this.sources = sources;
        }
    
    }

对象BaseInfo

package com.trs.idap.web.rest.util;
    
    import java.io.Serializable;
    import java.util.Arrays;
    
    /**
     * Created by Administrator on 2018/7/25.
     * 描述:
     *
     * @author Young
     * @create 2018-07-25 17:47
     */
    public class BaseInfo implements Serializable{
        private BaseList baseList;
        private InfoList[] infoList;
        
        //TODO getter/setter/toString
    }

对象BaseList

package com.trs.idap.web.rest.util;
    
    import java.io.Serializable;
    import java.util.Arrays;
    
    /**
     * Created by Administrator on 2018/7/25.
     * 描述:
     *
     * @author Young
     * @create 2018-07-25 17:59
     */
    public class BaseList implements Serializable{
        private String tableName;
        private String tableNameDesc;
        private String tableAlias;
        private String tableSize;
        private TableFields[]  tableFields;
    
       //TODO setter getter toString
    }

对象 TableFields

package com.trs.idap.web.rest.util;
    
    import java.io.Serializable;
    
    /**
     * Created by Administrator on 2018/7/25.
     * 描述:
     *
     * @author Young
     * @create 2018-07-25 18:02
     */
    public class TableFields implements Serializable{
        private String field;
        private String fieldDesc;
        private String fieldInputtype;
    
     //TODO setter getter toString
    }

对象InfoList

package com.trs.idap.web.rest.util;
    
    import java.io.Serializable;
    
    /**
     * Created by Administrator on 2018/7/25.
     * 描述:
     *
     * @author Young
     * @create 2018-07-25 18:04
     */
    public class InfoList implements Serializable {
        private String field;
        private String fieldContent;
        private String fieldDesc;
    
       //TODO getter setter toString
    }

对象OutFields

package com.trs.idap.web.rest.util;
    
    import java.io.Serializable;
    
    /**
     * Created by Administrator on 2018/7/25.
     * 描述:
     *
     * @author Young
     * @create 2018-07-25 17:55
     */
    public class OutFields implements Serializable {
        private String field;
        private String fieldDesc;
        private String fieldInputtype;
    
      //TODO getter setter toString
    }

由上图可见.....该json总共建立了6个java对象.但是对于后期的维护性还是比较方便的....

使用方法解析时:

package com.trs.idap.web.rest.util;
    
    import com.fasterxml.jackson.databind.ObjectMapper;
    
    import java.io.IOException;
    
    /**
     * Created by Administrator on 2018/7/25.
     * 描述:解析json格式
     *
     * @author Young
     * @create 2018-07-25 17:07
     */
    public class JsonUtils {
        public static void main(String[] args) throws IOException {
            ObjectMapper mapper = new ObjectMapper();
            JsonValue jsonValue = mapper.readValue(jsonString, JsonValue.class);
    
            OutFields[] outFields = jsonValue.getOutFields();
            //字段值,字段   ===>columnList columnListComment
            StringBuffer sbFieldList = new StringBuffer();
            StringBuffer sbFieldListComment = new StringBuffer();
            Boolean flag = false;
            for (OutFields outField : outFields) {
                System.err.println(outField.getField());
                System.out.println(outField.getFieldDesc());
                System.out.println(outField.getFieldInputtype());
                if (!flag) {
                    sbFieldList.append(outField.getField());
                    sbFieldListComment.append(outField.getFieldDesc());
                    flag = true;
                } else {
                    sbFieldList.append(",").append(outField.getField());
                    sbFieldListComment.append(",").append(outField.getFieldDesc());
                }
            }
            System.out.println("字段列为:======>" + sbFieldList.toString() + ",   字段名为===:" + sbFieldListComment);
            BaseInfo[] sources = jsonValue.getSources();
            for (BaseInfo baseInfo : sources) {
                BaseList baseList = baseInfo.getBaseList();
                System.out.println(baseList.getTableAlias());
                System.out.println(baseList.getTableFields());
                System.out.println(baseList.getTableName());
                System.out.println(baseList.getTableNameDesc());
                System.out.println(baseList.getTableSize());
                InfoList[] infoList = baseInfo.getInfoList();
                for (InfoList info : infoList) {
                    System.out.println(info.getField());
                    System.out.println(info.getFieldContent());
                    System.out.println(info.getFieldDesc());
                }
            }
        }
    
      
    
    }

真正使用的就是获取到指定的类型

ObjectMapper mapper = new ObjectMapper();
            JsonValue jsonValue = mapper.readValue(jsonString, JsonValue.class);

构建起来还很方便的..只要将对象关系处理好.

[70]: /images/20220519/7acb77bcad2148eb9d9381b50f4b357c.png
[70 1]: /images/20220519/9bd8b4fdab45469c9166f9989e3af30b.png