Question

我对json很新，我在下面做了一个例子，虽然我遇到问题，但也试图以一种好的方式解析它

我正在使用Eclipse：
JRE系统库[Java1.8]
并使用库：
的 JSON-简单1.1.1.jar

我制作了以下JSON文件：

Available kernels:
  ir         C:\ProgramData\Anaconda3\share\jupyter\kernels\ir
  python3    C:\ProgramData\Anaconda3\share\jupyter\kernels\python3

这是我的脚本尝试读取文件

[
  [
    {
      "TestScenario_1": {
        "Transaction": "A",
        "description": "This is a test A",
        "Co-no": "",
        "Project": "Proj1"
      }
    }
  ],
  [
    {
      "TestScenario_2": {
        "Transaction": "B",
        "description": "This is a test B",
        "Co-no": "",
        "Project": "Proj2"
      }
    }
  ]
]

虽然我收到以下错误：

import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import org.json.simple.JSONArray;
import org.json.simple.JSONObject;
import org.json.simple.parser.JSONParser;
import org.json.simple.parser.ParseException;

public class JsonParseTest {

    private static final String filePath = "C:\\temp\\mytest2.json";

    @SuppressWarnings({ "unchecked", "unused", "rawtypes" })
    public static void main(String[] args) {

        try {


            // read the json file
            FileReader reader = new FileReader(filePath);

            JSONParser jsonParser = new JSONParser();
            JSONObject jo = (JSONObject) jsonParser.parse(reader);

            // get a String from the JSON object
            Long TestScenario=(Long) jo.get("TestScenario");
            System.out.println("TestScenario " + TestScenario);

            String Transaction=(String) jo.get("Transaction");
            System.out.println("Transaction " + Transaction);

            String Description=(String) jo.get("Description");
            System.out.println("Description " + Description);

            String Cono=(String) jo.get("Co-no");
            System.out.println("Co-no " + Cono);

            JSONArray Parameters= (JSONArray) jo.get("Parameters");


        } catch (FileNotFoundException ex) {
            ex.printStackTrace();
        } catch (IOException ex) {
            ex.printStackTrace();
        } catch (ParseException ex) {
            ex.printStackTrace();
        } catch (NullPointerException ex) {
            ex.printStackTrace();
        }

    }

}

有人可以帮助我吗？

提前谢谢

Answer 1

一个简单的方法可能是json字符串的递归方法，json数组和java中带有instanceof方法的对象。

所以，需要两个方法，一个用于json数组

private static void searchJSONArray(JSONArray arry) {
    JSONArray jarry = arry;
    JSONObject jobj = null;

    for (Iterator iter = jarry.iterator(); iter.hasNext();) {
        Object o = iter.next();
        if (o instanceof JSONArray) {
            searchJSONArray((JSONArray) o);
        } else if (o instanceof JSONObject) {
            jobj = (JSONObject) o;
            Set keyset = jobj.keySet();

            for (Iterator iter2 = keyset.iterator(); iter2.hasNext();) {
                String key = (String) iter2.next();
                Object value = jobj.get(key);

                if(value instanceof JSONObject)
                {
                    System.out.println("[" + key + "]");
                    searchJSONObject((JSONObject)value);
                }
                else
                {
                    System.out.println(key + "=" + (String)value);
                }
            }
        }

    }
}

和json对象的另一个。

private static void searchJSONObject(JSONObject obj) {
    JSONObject jobj = obj;

    Set keyset = jobj.keySet();

    for (Iterator iter2 = keyset.iterator(); iter2.hasNext();) {
        String key = (String) iter2.next();
        Object value = jobj.get(key);

        if(value instanceof JSONObject)
        {
            searchJSONObject((JSONObject)value);
        }
        else
        {
            System.out.println(key + "=" + (String)value);
        }
    }

}

然后，完整的来源如下;

package com.tobee.tests.parse.json;

import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.util.Iterator;
import java.util.Set;

import org.json.simple.JSONArray;
import org.json.simple.JSONObject;
import org.json.simple.parser.JSONParser;
import org.json.simple.parser.ParseException;

public class JsonParseTest {

    private static final String filePath = "resource/aa/mytest2.json";

    private static void searchJSONObject(JSONObject obj) {
        JSONObject jobj = obj;

        Set keyset = jobj.keySet();

        for (Iterator iter2 = keyset.iterator(); iter2.hasNext();) {
            String key = (String) iter2.next();
            Object value = jobj.get(key);

            if(value instanceof JSONObject)
            {
                searchJSONObject((JSONObject)value);
            }
            else
            {
                System.out.println(key + "=" + (String)value);
            }
        }

    }

    private static void searchJSONArray(JSONArray arry) {
        JSONArray jarry = arry;
        JSONObject jobj = null;

        for (Iterator iter = jarry.iterator(); iter.hasNext();) {
            Object o = iter.next();
            if (o instanceof JSONArray) {
                searchJSONArray((JSONArray) o);
            } else if (o instanceof JSONObject) {
                jobj = (JSONObject) o;
                Set keyset = jobj.keySet();

                for (Iterator iter2 = keyset.iterator(); iter2.hasNext();) {
                    String key = (String) iter2.next();
                    Object value = jobj.get(key);

                    if(value instanceof JSONObject)
                    {
                        System.out.println("[" + key + "]");
                        searchJSONObject((JSONObject)value);
                    }
                    else
                    {
                        System.out.println(key + "=" + (String)value);
                    }
                }
            }

        }
    }

    public static void main(String[] args) {

        try {

            // read the json file
            FileReader reader = new FileReader(filePath);

            JSONParser jsonParser = new JSONParser();

            Object jsonThing = jsonParser.parse(reader);

            if (jsonThing instanceof JSONArray) {
                searchJSONArray((JSONArray) jsonThing);
            } else if (jsonThing instanceof JSONObject) {
                JSONObject jobj = (JSONObject) jsonThing;

                Set keyset = jobj.keySet();

                for (Iterator iter2 = keyset.iterator(); iter2.hasNext();) {
                    String key = (String) iter2.next();
                    String value = (String) jobj.get(key);

                    System.out.println(key + "=" + value);

                }
            }

        } catch (FileNotFoundException ex) {
            ex.printStackTrace();
        } catch (IOException ex) {
            ex.printStackTrace();
        } catch (ParseException ex) {
            ex.printStackTrace();
        } catch (NullPointerException ex) {
            ex.printStackTrace();
        }

    }

    @SuppressWarnings({ "unchecked", "unused", "rawtypes" })
    public static void your_main(String[] args) {

        try {

            // read the json file
            FileReader reader = new FileReader(filePath);

            JSONParser jsonParser = new JSONParser();
            JSONObject jo = (JSONObject) jsonParser.parse(reader);

            // get a String from the JSON object
            Long TestScenario = (Long) jo.get("TestScenario");
            System.out.println("TestScenario " + TestScenario);

            String Transaction = (String) jo.get("Transaction");
            System.out.println("Transaction " + Transaction);

            String Description = (String) jo.get("Description");
            System.out.println("Description " + Description);

            String Cono = (String) jo.get("Co-no");
            System.out.println("Co-no " + Cono);

            JSONArray Parameters = (JSONArray) jo.get("Parameters");

        } catch (FileNotFoundException ex) {
            ex.printStackTrace();
        } catch (IOException ex) {
            ex.printStackTrace();
        } catch (ParseException ex) {
            ex.printStackTrace();
        } catch (NullPointerException ex) {
            ex.printStackTrace();
        }

    }

}

输出在这里

[TestScenario_1]
Co-no=
Project=Proj1
Transaction=A
description=This is a test A
[TestScenario_2]
Co-no=
Project=Proj2
Transaction=B
description=This is a test B

Answer 2

[
  {
  "TestScenario_1": {
    "Transaction": "A",
    "description": "This is a test A",
    "Co-no": "",
    "Project": "Proj1"
  }
 },
  {
  "TestScenario_2": {
    "Transaction": "B",
    "description": "This is a test B",
    "Co-no": "",
    "Project": "Proj2"
  }
 }
]

然后

FileReader reader = new FileReader(filePath);

JSONParser jsonParser = new JSONParser();
JSONArray jo = (JSONArray) jsonParser.parse(reader);

// get a String from the JSON object
JSONObject testScenario=(JSONObject) ((JSONObject)jo.get(0)).get("TestScenario_1");

Long transaction = (Long)testScenario.get("Transaction");
System.out.println("transaction " + transaction);

`

使用for循环迭代JSONArray ......我只是举个例子

不能投json

2 个答案: