Question

我通过JavaScript对Jersey资源进行AJAX调用，其中类映射到/ books，GET方法映射到/ allBooks。这是AJAX调用的代码：

function libBooks(){

    alert("Inside js");
    //The above alert is displayed

    var requestData = {
            "dataType":  "application/json",
            "type":   "GET",
            "url":    "http://localhost:8080/library/rest/books/allBooks/"
    };

    var request = $.ajax(requestData);
    alert("Ajax call made");
    //The above alert is displayed

    request.success(function(data) {

        alert("Inside done function");
        //The above alert is not displayed
        var dataReceived =data.listOfBooks;
        var numOfItems = dataReceived.length;
        alert(numOfItems);

    });

    request.fail(function(jqXHR, status, errorMessage) {
        if((errorMessage = $.trim(errorMessage)) === "") {
            alert("An unspecified error occurred.  Check the server error log for details.");
        }
        else {
            alert("An error occurred:  " + errorMessage);
        }
    });

}

在JSP中我有这样的链接：

<p>List of books in library  <a href="" onclick="libBooks();">Click Here</a></p>

这是我的BookResource：

@Path("/books")
public class BookResource {

    @GET
    @Path("/allBooks")
    @Produces(MediaType.APPLICATION_JSON)
    public Response getAllBooks() {

        BooksHelper bookHelper = new BooksHelper();
        ArrayList<Book> listOfBooks = bookHelper.getListOfBooks();

        ResponseBuilder responseBuilder = Response.status(Status.OK);
        responseBuilder.entity(listOfBooks);

        Response response = responseBuilder.build();
        return response;            
    }
}

这是我的pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">

    <modelVersion>4.0.0</modelVersion>

    <groupId>org.sudhanshu</groupId>
    <artifactId>library</artifactId>
    <packaging>war</packaging>
    <version>0.0.1-SNAPSHOT</version>
    <name>library</name>

    <build>
        <finalName>library</finalName>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>2.5.1</version>
                <inherited>true</inherited>
                <configuration>
                    <source>1.7</source>
                    <target>1.7</target>
                </configuration>
            </plugin>
        </plugins>
    </build>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.glassfish.jersey</groupId>
                <artifactId>jersey-bom</artifactId>
                <version>${jersey.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>

    <dependencies>
        <dependency>
            <groupId>org.glassfish.jersey.containers</groupId>
            <artifactId>jersey-container-servlet-core</artifactId>
            <!-- use the following artifactId if you don't need servlet 2.x compatibility -->
            <!-- artifactId>jersey-container-servlet</artifactId -->
        </dependency>
        <!-- uncomment this to get JSON support
        <dependency>
            <groupId>org.glassfish.jersey.media</groupId>
            <artifactId>jersey-media-moxy</artifactId>
        </dependency>
        -->
      <dependency>
    <groupId>javax.servlet</groupId>
    <artifactId>jstl</artifactId>
    <version>1.2</version>
</dependency>

<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <version>5.1.6</version>
</dependency>

    </dependencies>
    <properties>
        <jersey.version>2.16</jersey.version>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>
</project>

我不确定pom.xml中的映射是如何工作的，因为我是第一次使用Maven。这是我的web.xml：

<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" version="2.5">
  <servlet>
    <servlet-name>Jersey Web Application</servlet-name>
    <servlet-class>org.glassfish.jersey.servlet.ServletContainer</servlet-class>
    <init-param>
      <param-name>jersey.config.server.provider.packages</param-name>
      <param-value>org.sudhanshu.library</param-value>
    </init-param>
    <load-on-startup>1</load-on-startup>
  </servlet>

  <servlet-mapping>
    <servlet-name>Jersey Web Application</servlet-name>
    <url-pattern>/rest/*</url-pattern>
  </servlet-mapping>
</web-app>

当我到达URL：http://localhost:8080/library/rest/books/allBooks时，它说资源找不到404.我认为问题可能出在web.xml REST请求入口点和我在Resource中的映射。另外，请建议我的ajax请求中的URL是否正确。我尝试了各种各样的东西，但没有一个在起作用。现在我只想要一个警告，显示ajax调用成功。这是我的目录结构：任何帮助将不胜感激。谢谢。

enter image description here

Answer 1

看这里

<init-param>
  <param-name>jersey.config.server.provider.packages</param-name>
  <param-value>org.sudhanshu.library</param-value>
</init-param>

您指定要扫描的包是org.sudhanshu.library。查看项目结构的图像，该包是空的。您应正在扫描的软件包是com.resources

第二件事（与404无关，但将成为下一个问题）是你需要一个JSON提供者。您可以在生成的pom.xml文件中看到它们提供了一个提示

<!-- uncomment this to get JSON support
<dependency>
    <groupId>org.glassfish.jersey.media</groupId>
    <artifactId>jersey-media-moxy</artifactId>
</dependency>
-->

您需要取消注释该依赖项。另外，我会将依赖项从jersey-media-moxy更改为jersey-media-json-jackson。 IMO杰克逊在许多方面比MOXy做得更好。

Answer 2

这帮助我找出了我的问题：我遇到了同样的问题（资源未找到），我试图建立我的<param-value>标签，只包含资源所在的软件包的名称（不是nameOfMyApp .myResource）。我认为知道同样很少的同事也会有同样的错误。

泽西岛找不到资源（错误404）

2 个答案: