从Intellij切换到Maven build时Java的空指针异常

我在使用Intellij构建时使用了一些代码。我切换到Maven是因为我想要一个易于执行的jar文件，但现在服务的行为方式不同了

我希望能做到

curl-X POSThttp://localhost:8080/api/values --数据“value=10”

并在此处接收：

@Path("api/values")
public class Receive {
    @EJB
    Tracker tracker;

    @POST
    @Consumes(MediaType.APPLICATION_FORM_URLENCODED)
    @Produces(MediaType.TEXT_PLAIN)
    public Response doPost(@FormParam("value") int val) {
        Logger l = Logger.getLogger("org.glassfish.grizzly.http.server.HttpHandler");
        l.setLevel(Level.FINE);
        l.setUseParentHandlers(false);
        ConsoleHandler ch = new ConsoleHandler();
        ch.setLevel(Level.ALL);
        l.addHandler(ch);
        l.log(Level.FINE, val);
        tracker.increaseSum(10);
        return Response.status(200).entity("ok").build();
    }

    @GET
    @Produces(MediaType.TEXT_PLAIN)
    public String getIt() {
        return "Got it!";
    }

但我现在得到一个空指针异常：

Apr 30, 2017 5:35:07 PM org.glassfish.grizzly.http.server.HttpHandler$1 run
FINE: service exception
java.lang.NullPointerException
    at com.underdog.jersey.grizzly.Receive.doPost(Receive.java:35)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.glassfish.jersey.server.model.internal.ResourceMethodInvocationHandlerFactory$1.invoke(ResourceMethodInvocationHandlerFactory.java:81)
    at org.glassfish.jersey.server.model.internal.AbstractJavaResourceMethodDispatcher$1.run(AbstractJavaResourceMethodDispatcher.java:164)
    at org.glassfish.jersey.server.model.internal.AbstractJavaResourceMethodDispatcher.invoke(AbstractJavaResourceMethodDispatcher.java:181)
    at org.glassfish.jersey.server.model.internal.JavaResourceMethodDispatcherProvider$ResponseOutInvoker.doDispatch(JavaResourceMethodDispatcherProvider.java:158)
    at org.glassfish.jersey.server.model.internal.AbstractJavaResourceMethodDispatcher.dispatch(AbstractJavaResourceMethodDispatcher.java:101)
    at org.glassfish.jersey.server.model.ResourceMethodInvoker.invoke(ResourceMethodInvoker.java:389)
    at org.glassfish.jersey.server.model.ResourceMethodInvoker.apply(ResourceMethodInvoker.java:347)
    at org.glassfish.jersey.server.model.ResourceMethodInvoker.apply(ResourceMethodInvoker.java:102)
    at org.glassfish.jersey.server.ServerRuntime$2.run(ServerRuntime.java:305)
    at org.glassfish.jersey.internal.Errors$1.call(Errors.java:271)
    at org.glassfish.jersey.internal.Errors$1.call(Errors.java:267)
    at org.glassfish.jersey.internal.Errors.process(Errors.java:315)
    at org.glassfish.jersey.internal.Errors.process(Errors.java:297)
    at org.glassfish.jersey.internal.Errors.process(Errors.java:267)
    at org.glassfish.jersey.process.internal.RequestScope.runInScope(RequestScope.java:317)
    at org.glassfish.jersey.server.ServerRuntime.process(ServerRuntime.java:288)
    at org.glassfish.jersey.server.ApplicationHandler.handle(ApplicationHandler.java:1110)
    at org.glassfish.jersey.grizzly2.httpserver.GrizzlyHttpContainer.service(GrizzlyHttpContainer.java:381)
    at org.glassfish.grizzly.http.server.HttpHandler$1.run(HttpHandler.java:219)
    at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:565)
    at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.run(AbstractThreadPool.java:545)
    at java.lang.Thread.run(Thread.java:748)

我的pom中是否缺少依赖项？简单的

@GET

方法似乎运行良好

编辑：所做的更改：

@Path("/api/values")
public class Receive {

    @Inject
    public Tracker tracker;

    @POST
    @Consumes(MediaType.APPLICATION_FORM_URLENCODED)
    @Produces(MediaType.TEXT_PLAIN)
    public String doPost(@FormParam("value") int val) {
        this.tracker.increaseSum(val);
        return "\nok\n";
    }

    // Tell the tracker to set sum == 0, effectively "erasing" the "stored"
    // values.
    @DELETE
    @Produces(MediaType.TEXT_PLAIN)
    public Response deleteSum() {
        this.tracker.clearSum();
        return Response.status(200).entity("\nok\n").build();
    }
}

@Path("/api/sum/values")
public class Send {
    @Inject
    public Tracker tracker;

    @GET
    @Produces("text/plain")
    function
}

@Immediate
public class Tracker {
    ...
    @PostConstruct
    function 

    @PreDestroy
    function

    @Lock(LockType.READ)
    function
}

//Defines the base URI for all resource URIs.
@ApplicationPath("/api")
public class AppConfig extends ResourceConfig {

    public AppConfig() {
        packages(true, "com.underdog.jersey.grizzly");
        register(new AbstractBinder() {
            @Override
            protected void configure() {
                bind(Tracker.class)
                    .to(Tracker.class)
                    .in(Immediate.class);
            }
        });
    }
}

mvn清洁包后出现错误

[ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:2.5.1:compile (default-compile) on project jersey-grizzly: Compilation failure: Compilation failure:
[ERROR] /home/user/kochava/simple-service/src/main/java/com/underdog/jersey/grizzly/Tracker.java:[18,7] error: duplicate class: Tracker
[ERROR] /home/user/kochava/simple-service/src/main/java/com/underdog/jersey/grizzly/Send.java:[16,11] error: cannot access Tracker
[ERROR] -> [Help 1]
[ERROR] 
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR] 
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/MojoFailureException

---

如果您没有运行EE容器，那么EJB将无法工作。您应该去掉项目中的任何EE依赖项，这样您就不会试图使用任何不起作用的东西

---

相反，您应该只使用Jersey内部DI系统HK2来处理服务注入。

tracker为

null

。我想它需要以某种方式被实例化。所以我试着浏览那个文档。我创建了一个扩展

ResourceConfig

的类，注册了一个

AbstractBinder

，通过将

Tracker

绑定到

Immediate

中的

Tracker

（因为Tracker在服务启动和销毁时需要做一些事情）并将

@Singleton

替换为

@Immediate

作为类的注释。我有两个类试图

@注入
跟踪器。现在编译错误是，
Tracker
是一个重复的类，
Send
，另一个类访问它，不能访问它。还有其他建议吗？是的。将您所做的作为编辑发布到您的帖子中，并发布完整的错误。没有它我就无能为力。“你说的对米尔赖特来说没有多大意义，”编辑说。让我知道如果这更有意义，我是100%新的东西。还有，谢谢你的帮助。我不知道这是什么意思。我从来没见过。这是一个编译错误，所以这是您在编码中没有正确执行的部分。不确定它是什么。您需要启用立即作用域。看见