在 Java 中创建一个简单的 Restful api

Creating a simple Restful api in Java

我正在尝试通过 intellij 创建一个简单的 Restful hello world api。我用 maven-archetype-quickstart 创建了一个 maven 项目,然后在 pom.xml 中添加了

<dependency>
  <groupId>org.jboss.resteasy</groupId>
  <artifactId>resteasy-jaxrs</artifactId>
  <version>2.3.7.Final</version>
  <scope>provided</scope>
</dependency>

然后在 src->main->java->webservice 我有两个文件: App.java

    package webservice;

/**
 * Hello world!
 *
 */
public class App 
{
    public static void main( String[] args )
    {
        System.out.println( "Hello World!" );
    }
}

和BookRestService.java

package webservice;

import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;

@Path("/book")
public class BookRestService {
    @GET
    @Produces("text/plain")
    public String getBookTitle() {
        return "H2G2";
    }
}

我正在使用 jBoss-6.4。 Jboss 似乎开始给我以下信息:

15:08:01,550 INFO  [org.jboss.ws.common.management] (MSC service thread 1-2) JBWS022052: Starting JBoss Web Services - Stack CXF Server 4.3.4.Final-redhat-1
15:08:01,824 INFO  [org.jboss.as.remoting] (MSC service thread 1-1) JBAS017100: Listening on 127.0.0.1:4447
15:08:01,824 INFO  [org.jboss.as.remoting] (MSC service thread 1-7) JBAS017100: Listening on 127.0.0.1:9999
15:08:01,827 INFO  [org.jboss.as.server.deployment.scanner] (MSC service thread 1-3) JBAS015012: Started FileSystemDeploymentService for directory /home/symeon/myprojects/applicationserver/jboss-eap-6.4-clean/standalone/deployments
15:08:02,113 INFO  [org.jboss.as] (Controller Boot Thread) JBAS015961: Http management interface listening on http://127.0.0.1:9990/management
15:08:02,114 INFO  [org.jboss.as] (Controller Boot Thread) JBAS015951: Admin console listening on http://127.0.0.1:9990
15:08:02,115 INFO  [org.jboss.as] (Controller Boot Thread) JBAS015874: JBoss EAP 6.4.0.GA (AS 7.5.0.Final-redhat-21) started in 5345ms - Started 153 of 191 services (57 services are lazy, passive or on-demand)
Connected to server
[2019-01-24 03:08:02,544] Artifact webservice: Artifact is being deployed, please wait...
15:08:02,721 INFO  [org.jboss.as.server.deployment] (MSC service thread 1-6) JBAS015876: Starting deployment of "webservice" (runtime-name: "webservice.war")
15:08:03,236 INFO  [org.jboss.web] (ServerService Thread Pool -- 7) JBAS018210: Register web context: /webservice
15:08:03,400 INFO  [org.jboss.as.server] (management-handler-thread - 2) JBAS015859: Deployed "webservice" (runtime-name : "webservice.war")
[2019-01-24 03:08:03,428] Artifact webservice: Artifact is deployed successfully
[2019-01-24 03:08:03,428] Artifact webservice: Deploy took 884 milliseconds

我期望的是当我打开浏览器并写入 http://localhost:8080/book to see H2G2 as answer. I have also tried http://localhost:8080/webservice/book 时,因为它提到 Web 上下文已注册到 /webservice 但再次没有成功。我收到 404 Not Found 错误。我做错了什么?

Register web context: /webservice

表示您编码的所有路径都必须在/webservice 之后。 所以你应该使用 http://localhost:8080/webservice/book

而不是 http://localhost:8080/book

默认情况下,resteasy 不会扫描您的整个项目以获取服务 class。你需要告诉 resteasy 来扫描它。在 web.xml 中使用以下代码启用扫描。

<context-param>
    <param-name>resteasy.scan</param-name>
    <param-value>true</param-value>
</context-param>

Source

在您的 App.java 中,您需要定义 ApplicationPath。如下所示。

import java.util.HashSet;
import java.util.Set;

import javax.ws.rs.ApplicationPath;
import javax.ws.rs.core.Application;

@ApplicationPath("/restRoot")
public class App extends Application {

    @Override
    public Set<Class<?>> getClasses() {
        HashSet<Class<?>> classes = new HashSet<Class<?>>();
        classes.add(BookRestService.class);

        return classes;
    }
}

在此之后您的 REST url 将变为

http://localhost:8080/webservice/restRoot/book