Guide de JavaLite - Construction d’une application RESTful CRUD

<dependency>
    <groupId>org.javalite</groupId>
    <artifactId>activeweb</artifactId>
    <version>1.15</version>
</dependency>

<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <version>5.1.45</version>
</dependency>

<plugin>
    <groupId>org.javalite</groupId>
    <artifactId>activejdbc-instrumentation</artifactId>
    <version>1.4.13</version>
    <executions>
        <execution>
            <phase>process-classes</phase>
            <goals>
                <goal>instrument</goal>
            </goals>
        </execution>
    </executions>
</plugin>

@RESTful
public class ProductsController extends AppController {

    public void index() {
       //...
    }

}

http://<host>:<port>/products

@RESTful
public class ProductsController extends AppController {

    public void index() {
       //code to get all products
    }

    public void create() {
       //code to create a new product
    }

    public void update() {
       //code to update an existing product
    }

    public void show() {
       //code to find one product
    }

    public void destroy() {
       //code to remove an existing product
    }
}

src
 |----main
       |----java.app
       |     |----config
       |     |----controllers
       |     |----models
       |----resources
       |----webapp
             |----WEB-INF
             |----views

public class DbConfig extends AbstractDBConfig {
    @Override
    public void init(AppContext appContext) {
        this.configFile("/database.properties");
    }
}

development.driver=com.mysql.jdbc.Driver
development.username=user
development.password=password
development.url=jdbc:mysql://localhost/dbname

public class AppControllerConfig extends AbstractControllerConfig {

    @Override
    public void init(AppContext appContext) {
        add(new DBConnectionFilter()).to(ProductsController.class);
    }
}

public class AppBootstrap extends Bootstrap {
    public void init(AppContext context) {}
}

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns=...>

    <filter>
        <filter-name>dispatcher</filter-name>
        <filter-class>org.javalite.activeweb.RequestDispatcher</filter-class>
        <init-param>
            <param-name>exclusions</param-name>
            <param-value>css,images,js,ico</param-value>
        </init-param>
        <init-param>
            <param-name>encoding</param-name>
            <param-value>UTF-8</param-value>
        </init-param>
    </filter>

    <filter-mapping>
        <filter-name>dispatcher</filter-name>
        <url-pattern>/** </url-pattern>
    </filter-mapping>

</web-app>

@RESTful
public class ProductsController extends AppController {

    private ObjectMapper mapper = new ObjectMapper();

    public void index() {
        List<Product> products = Product.findAll();
       //...
    }

    public void create() {
        Map payload = mapper.readValue(getRequestString(), Map.class);
        Product p = new Product();
        p.fromMap(payload);
        p.saveIt();
       //...
    }

    public void update() {
        Map payload = mapper.readValue(getRequestString(), Map.class);
        String id = getId();
        Product p = Product.findById(id);
        p.fromMap(payload);
        p.saveIt();
       //...
    }

    public void show() {
        String id = getId();
        Product p = Product.findById(id);
       //...
    }

    public void destroy() {
        String id = getId();
        Product p = Product.findById(id);
        p.delete();
       //...
    }
}

{
    "id" : ${product.id},
    "name" : "${product.name}"
}

----[<@render partial="product" collection=products/>]----

@RESTful
public class ProductsController extends AppController {

    public void index() {
        List<Product> products = Product.findAll();
        view("products", products);
        render();
    }

    public void show() {
        String id = getId();
        Product p = Product.findById(id);
        view("product", p);
        render("__product");
    }
}

{
    "message" : "${message}",
    "code" : ${code}
}

view("message", "There was an error.", "code", 200);
render("message");

@RESTful
public class ProductsController extends AppController {

    private ObjectMapper mapper = new ObjectMapper();

    public void index() {
        view("products", Product.findAll());
        render().contentType("application/json");
    }

    public void create() {
        Map payload = mapper.readValue(getRequestString(), Map.class);
        Product p = new Product();
        p.fromMap(payload);
        p.saveIt();
        view("message", "Successfully saved product id " + p.get("id"), "code", 200);
        render("message");
    }

    public void update() {
        Map payload = mapper.readValue(getRequestString(), Map.class);
        String id = getId();
        Product p = Product.findById(id);
        if (p == null) {
            view("message", "Product id " + id + " not found.", "code", 200);
            render("message");
            return;
        }
        p.fromMap(payload);
        p.saveIt();
        view("message", "Successfully updated product id " + id, "code", 200);
        render("message");
    }

    public void show() {
        String id = getId();
        Product p = Product.findById(id);
        if (p == null) {
            view("message", "Product id " + id + " not found.", "code", 200);
            render("message");
            return;
        }
        view("product", p);
        render("__product");
    }

    public void destroy() {
        String id = getId();
        Product p = Product.findById(id);
        if (p == null) {
            view("message", "Product id " + id + " not found.", "code", 200);
            render("message");
            return;
        }
        p.delete();
        view("message", "Successfully deleted product id " + id, "code", 200);
        render("message");
    }

    @Override
    protected String getContentType() {
        return "application/json";
    }

    @Override
    protected String getLayout() {
        return null;
    }
}

<plugin>
    <groupId>org.eclipse.jetty</groupId>
    <artifactId>jetty-maven-plugin</artifactId>
    <version>9.4.8.v20171121</version>
</plugin>

mvn jetty:run

$ curl -X POST http://localhost:8080/products
  -H 'content-type: application/json'
  -d '{"name":"Water"}'
{
    "message" : "Successfully saved product id 1",
    "code" : 200
}

$ curl -X POST http://localhost:8080/products
  -H 'content-type: application/json'
  -d '{"name":"Bread"}'
{
    "message" : "Successfully saved product id 2",
    "code" : 200
}

$ curl -X GET http://localhost:8080/products[    {
        "id" : 1,
        "name" : "Water"
    },
    {
        "id" : 2,
        "name" : "Bread"
    }]----

.. mettre à jour l'un d'entre eux:

[source,bash,gutter:,true]

... lisez celui que nous venons de mettre à jour:

[source,bash,gutter:,true]

Enfin, nous pouvons en supprimer un:

[source,bash,gutter:,true]

[[conclusions]]

===  **  9. Conclusion**

JavaLite propose de nombreux outils pour aider les développeurs à **  mettre en place une application en quelques minutes ** . Cependant, si le fait de se baser sur des conventions donne un code plus propre et plus simple, il faut un certain temps pour comprendre le nom et l'emplacement des classes, des packages et des fichiers.

Ce n'était qu'une introduction à ActiveWeb et ActiveJDBC, retrouvez plus de documentation sur leur http://javalite.io[site web]et recherchez notre application de produits dans https://github.com/eugenp/tutorials/tree/master/java- Lite[le projet Github].