# JsonParser2.0

**Repository Path**: warrior__night/JsonParser2.0

## Basic Information

- **Project Name**: JsonParser2.0
- **Description**: 手写Json解析器，使用了生成式理论来分析各个部分，而且完成了序列化的功能。
- **Primary Language**: Unknown
- **License**: Not specified
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 0
- **Created**: 2021-05-18
- **Last Updated**: 2021-05-18

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

# 项目：Json解析器2.0
这是我的Json解析器2.0版本，使用了编译原理的一些原理，
通过自定义的生成式来解析Json字符串为自定义的对象，并且完成了将对象转换为Json字符串的功能（即反序列化）

测试1：
```json
# first.json
{
  "name": "mike",
  "age": 10,
  "height": 168.5,
  "friends": ["John", "Sara", "CodeReaper"],
  "family": {
    "mom": "Holom",
    "dad": "Geo"
  },
  "message": "his old name is \"haha\""
}
```
代码
```java
String filePath = "testFile/first.json";
String codeText = readJsonText(filePath);
Lexer lexer = new Lexer(codeText);
Parser parser = new Parser(lexer);
ObjectVal dict = (ObjectVal) parser.parse();

JsonPrinter jsonPrinter = new JsonPrinter();
jsonPrinter.printValue(dict);

System.out.println("\nfriends: ");
ArrayVal friends = (ArrayVal) dict.getValue("friends");
for (JsonVal jsonVal : friends.getValueList()) {
    System.out.println(jsonVal);
}

System.out.println("\nfamily:");
ObjectVal family = (ObjectVal) dict.getValue("family");
jsonPrinter.printValue(family);
```
运行输出：
```
{
    "name": "mike",
    "family": {
        "dad": "Geo",
        "mom": "Holom"
    },
    "message": "his old name is \"haha\"",
    "age": 10.0,
    "friends": [
        "John",
        "Sara",
        "CodeReaper"
    ],
    "height": 168.5
}


friends: 
"John"
"Sara"
"CodeReaper"

family:
{
    "dad": "Geo",
    "mom": "Holom"
}
```

测试2：测试反序列化
```java
ObjectVal personInfo = new ObjectVal();
personInfo.putKeyVal("name","codeReaper");
personInfo.putKeyVal("age",new NumVal(20));
ArrayVal hobbies = new ArrayVal();
hobbies.addValue("coding");
hobbies.addValue("lol");
hobbies.addValue("playing pingpong");
personInfo.putKeyVal("hobbies", hobbies);

JsonPrinter jsonPrinter = new JsonPrinter();
jsonPrinter.printValue(personInfo);

System.out.println("--------");
String serializedStr = jsonPrinter.getSerializedStr(personInfo);
System.out.println(serializedStr);
```
运行输出：
```json
{
    "hobbies": [
        "coding",
        "lol",
        "playing pingpong"
    ],
    "name": "codeReaper",
    "age": 20.0
}
```

测试3：数组类型json 
```json
# array.json
[
  {
    "id": 15,
    "article_tags": [
      {
        "id": 9,
        "tag_name": "日常"
      }
    ],
    "create_time": "2021-04-26T04:30:20.161820Z",
    "update_time": "2021-04-26T15:06:18.641641Z",
    "article_title": "第一篇博客",
    "article_abstract": "第一篇博客",
    "article_content": "# 标题\n## 子标题\n- 1\n- 2\n- 3\n- 4\n1. java\n2. python\n3. js\n```java\nclass Person{\n    void sayHello(){\n        System.out.println(\"Hello\");\n    }\n}\n```\n![image.png](http://127.0.0.1:8000/media/image_c3uq8Wk.png)"
  },
  {
    "id": 16,
    "article_tags": [
      {
        "id": 9,
        "tag_name": "日常"
      }
    ],
    "create_time": "2021-04-26T10:27:19.423945Z",
    "update_time": "2021-04-26T10:27:19.423945Z",
    "article_title": "编辑",
    "article_abstract": "编辑",
    "article_content": "编辑"
  },
  {
    "id": 17,
    "article_tags": [
      {
        "id": 1,
        "tag_name": "c++基础内容"
      }
    ],
    "create_time": "2021-04-26T10:30:47.436020Z",
    "update_time": "2021-04-26T10:30:47.436020Z",
    "article_title": "test",
    "article_abstract": "test",
    "article_content": "test"
  },
  ...
]
```
代码：
```java
Parser parser = ParserBuilder.produceParser("testFile/array.json");
ArrayVal articles = (ArrayVal) parser.parse();

JsonPrinter jsonPrinter = new JsonPrinter();
jsonPrinter.printValue(articles);
```
运行输出：
```json
[
    {
        "update_time": "2021-04-26T15:06:18.641641Z",
        "article_title": "第一篇博客",
        "create_time": "2021-04-26T04:30:20.161820Z",
        "article_abstract": "第一篇博客",
        "article_content": "# 标题\n## 子标题\n- 1\n- 2\n- 3\n- 4\n1. java\n2. python\n3. js\n```java\nclass Person{\n    void sayHello(){\n        System.out.println(\"Hello\");\n    }\n}\n```\n![image.png](http://127.0.0.1:8000/media/image_c3uq8Wk.png)",
        "id": 15.0,
        "article_tags": [
            {
                "tag_name": "日常",
                "id": 9.0
            }
        ]
    },
    {
        "update_time": "2021-04-26T10:27:19.423945Z",
        "article_title": "编辑",
        "create_time": "2021-04-26T10:27:19.423945Z",
        "article_abstract": "编辑",
        "article_content": "编辑",
        "id": 16.0,
        "article_tags": [
            {
                "tag_name": "日常",
                "id": 9.0
            }
        ]
    },
    {
        "update_time": "2021-04-26T10:30:47.436020Z",
        "article_title": "test",
        "create_time": "2021-04-26T10:30:47.436020Z",
        "article_abstract": "test",
        "article_content": "test",
        "id": 17.0,
        "article_tags": [
            {
                "tag_name": "c++基础内容",
                "id": 1.0
            }
        ]
    },
    ...
]
```

测试4：取值
```json
# tags.json
[
  {
    "id": 1,
    "related_article_num": 1,
    "create_time": "2021-04-20T14:42:47.295950Z",
    "update_time": "2021-04-20T14:42:47.295950Z",
    "tag_name": "c++基础内容"
  },
  {
    "id": 2,
    "related_article_num": 0,
    "create_time": "2021-04-20T14:43:00.665498Z",
    "update_time": "2021-04-20T14:43:00.665498Z",
    "tag_name": "设计模式"
  },
  {
    "id": 3,
    "related_article_num": 0,
    "create_time": "2021-04-20T14:43:39.640646Z",
    "update_time": "2021-04-20T14:43:39.640646Z",
    "tag_name": "计算机系统2"
  },
  ...
]
```
代码：
```java
Parser parser = ParserBuilder.produceParser("testFile/tags.json");
ArrayVal articleArray = (ArrayVal) parser.parse();

JsonPrinter jsonPrinter = new JsonPrinter();
jsonPrinter.printValue(articleArray);

for (JsonVal val : articleArray.getValueList()) {
    ObjectVal obj = (ObjectVal)val;
    String tag_name = ((StringVal)obj.getValue("tag_name")).value;
    System.out.println(tag_name);
}
```
运行输出：
```
[
    {
        "update_time": "2021-04-20T14:42:47.295950Z",
        "create_time": "2021-04-20T14:42:47.295950Z",
        "tag_name": "c++基础内容",
        "related_article_num": 1.0,
        "id": 1.0
    },
    {
        "update_time": "2021-04-20T14:43:00.665498Z",
        "create_time": "2021-04-20T14:43:00.665498Z",
        "tag_name": "设计模式",
        "related_article_num": 0.0,
        "id": 2.0
    },
    {
        "update_time": "2021-04-20T14:43:39.640646Z",
        "create_time": "2021-04-20T14:43:39.640646Z",
        "tag_name": "计算机系统2",
        "related_article_num": 0.0,
        "id": 3.0
    },
    ...
]

c++基础内容
设计模式
计算机系统2
数据结构
555
心情
日常
新标签
哈哈
新
```