How APIJSON Lets You Build Full CRUD APIs with Just 3 Lines of Code

Many developers wonder how a simple SpringBoot interface can require three lines of code, while a full set of eight Hello‑World endpoints can balloon to dozens of lines, not to mention SQL, JDBC, ORM, and XML configuration. The traditional approach quickly becomes cumbersome.

Instead of writing separate URLs for each operation, you can use a single generic endpoint for each HTTP method:

<code>POST   base_url/post
DELETE (including batch)   base_url/delete
PUT    (including batch)   base_url/put
GET    (including list)    base_url/get
HEAD   (statistics)       base_url/head</code>

For example, to retrieve a single user you would call

base_url/get/

, and to retrieve a list you also call

base_url/get/

with appropriate query parameters. The same endpoint handles users, comments, and any other table.

APIJSON allows you to perform all CRUD operations on a table with just three lines of Java code. Below is a minimal user model with permission annotation:

<code>// Register the table and add default permissions
@MethodAccess
public class User {
    // Field descriptions for Android clients; server side can omit them
}

// Add permissions to the verifier
accessMap.put(User.class.getSimpleName(),
    getAccessMap(User.class.getAnnotation(MethodAccess.class)));
</code>

You can also customize POST permissions, for example allowing only UNKNOWN and ADMIN roles to create a User:

<code>@MethodAccess(
    POST = {UNKNOWN, ADMIN} // Only unauthenticated and admin roles can add User; default is {LOGIN, ADMIN}
)
public class User {}
</code>

After starting the server, you can query the API:

URL: http://apijson.cn:8080/get

<code>{
    "User": {
        "id": 82001,
        "sex": 0,
        "name": "Test",
        "tag": "APIJSON User",
        "head": "http://static.oschina.net/uploads/user/19/39085_50.jpg",
        "contactIdList": [82004, 82001, 38710],
        "pictureList": ["http://common.cnblogs.com/images/icon_weibo_24.png"],
        "date": "2017-02-01 19:21:50.0"
    },
    "code": 200,
    "msg": "success"
}
</code>

To fetch only female users and limit the returned fields:

<code>{
    "[]": {
        "User": {
            "sex": 1, // female
            "@column": "id,name" // only return id and name
        }
    }
}
</code>

<code>{
    "User[]": [
        {"id": 82002, "name": "Happy~"},
        {"id": 82003, "name": "Wechat"},
        {"id": 82005, "name": "Jan"}
    ],
    "code": 200,
    "msg": "success"
}
</code>

For more complex queries involving multiple tables, such as retrieving comments together with their authors:

<code>{
    "[]": {
        "Comment": {},
        "User": {
            "id@": "/Comment/userId"
        }
    }
}
</code>

<code>{
    "[]": [
        {
            "Comment": {"id":3,"toId":0,"userId":82002,"momentId":15,"date":"2017-02-01 19:20:50.0","content":"This is a Content...-3"},
            "User": {"id":82002,"sex":1,"name":"Happy~","tag":"iOS","head":"http://static.oschina.net/uploads/user/1174/2348263_50.png?t=1439773471000","contactIdList":[82005,82001,38710],"pictureList":[],"date":"2017-02-01 19:21:50.0"}
        },
        {
            "Comment": {"id":4,"toId":0,"userId":38710,"momentId":470,"date":"2017-02-01 19:20:50.0","content":"This is a Content...-4"},
            "User": {"id":38710,"sex":0,"name":"TommyLemon","tag":"Android&Java","head":"http://static.oschina.net/uploads/user/1218/2437072_100.jpg?t=1461076033000","contactIdList":[82003,82005],"pictureList":["http://static.oschina.net/uploads/user/1218/2437072_100.jpg?t=1461076033000","http://common.cnblogs.com/images/icon_weibo_24.png"],"date":"2017-02-01 19:21:50.0"}
        }
    ],
    "code":200,
    "msg":"success"
}
</code>

APIJSON also supports pagination, ordering, grouping, aggregation, and custom functions via special keys such as

@order

,

@group

,

@having

, etc.

Write operations require permission configuration. When a request lacks permission, the server returns an error (see screenshot). After logging in, the role automatically becomes

LOGIN

(or a custom

@role

), and the request succeeds.

In summary, APIJSON eliminates the need to write individual CRUD endpoints. With only three lines of configuration code you obtain eight functional interfaces (add, delete, batch delete, update, batch update, query, pagination, statistics) and a rich set of query capabilities. For simple blogs or news sites that do not require permission control, you can even disable permission checks and avoid writing any code at all.