java - 玩2.4 Finder抛出空指针异常

Question

我目前在 Play 2.4 中遇到一个 Finder 实例的问题，它在使用时返回空指针异常。这是尝试使用它的代码

public ExpressionList<ClientAuthorization> getAuthorizationQuery(String appId) {
        return ClientAuthorization.find.where().eq("app_id", appId).eq("active", 1);
    }

以及模型类

package models;

import com.avaje.ebean.Model;

import javax.persistence.*;
import java.sql.Timestamp;


@Entity
@Table(name="client_authorization")
public class ClientAuthorization extends Model {

    public static final Finder<Long, ClientAuthorization> find = new Finder<>(ClientAuthorization.class);


    @Id
    public long clientAuthorizationId;

    @Column(nullable=false, length=45)
    public String appId;

    @Column(nullable=false, length=45)
    public String apiKey;

    @Column(nullable=false)
    public boolean active;

    @Column(nullable = false)
    public boolean isAdmin;

    @Column(nullable=false)
    public Timestamp createdDate;

    @Column(nullable=false)
    public Timestamp updatedDate;

    @PrePersist
    protected void createdAt() {
        this.createdDate = new Timestamp(System.currentTimeMillis());
        this.updatedDate = new Timestamp(System.currentTimeMillis());
    }

    @PostPersist
    protected void updatedAt() {
        this.updatedDate = new Timestamp(System.currentTimeMillis());
    }


}

这对于我在 Play 中创建的每个模型都适用，所以我不确定发生了什么。这是我得到的内容

我非常感谢我能得到的任何帮助。这让我在我正在进行的升级项目中发疯。我上次的升级进展顺利，但这次却给我带来了问题。

附加信息:在 ClientAuthorization 静态调用 find 后调用 where() 失败

更新

既然它出现在评论中，这不仅仅是一个什么是 NPE 的问题，我已经知道了。由于某种原因，取景器未初始化。然而，看看这个模型以及我曾经编写过的每个模型，没有理由发生这种情况。

这是堆栈跟踪

@6o9455j27 - Internal server error, for (GET) [/] ->

play.api.http.HttpErrorHandlerExceptions$$anon$1: Execution exception[[NullPointerException: null]]
    at play.api.http.HttpErrorHandlerExceptions$.throwableToUsefulException(HttpErrorHandler.scala:265) ~[play_2.11-2.4.4.jar:2.4.4]
    at play.api.http.DefaultHttpErrorHandler.onServerError(HttpErrorHandler.scala:191) ~[play_2.11-2.4.4.jar:2.4.4]
    at play.api.GlobalSettings$class.onError(GlobalSettings.scala:179) [play_2.11-2.4.4.jar:2.4.4]
    at play.api.DefaultGlobal$.onError(GlobalSettings.scala:212) [play_2.11-2.4.4.jar:2.4.4]
    at play.api.http.GlobalSettingsHttpErrorHandler.onServerError(HttpErrorHandler.scala:94) [play_2.11-2.4.4.jar:2.4.4]
    at play.core.server.netty.PlayDefaultUpstreamHandler$$anonfun$9$$anonfun$apply$1.applyOrElse(PlayDefaultUpstreamHandler.scala:151) [play-netty-server_2.11-2.4.4.jar:2.4.4]
    at play.core.server.netty.PlayDefaultUpstreamHandler$$anonfun$9$$anonfun$apply$1.applyOrElse(PlayDefaultUpstreamHandler.scala:148) [play-netty-server_2.11-2.4.4.jar:2.4.4]
    at scala.runtime.AbstractPartialFunction.apply(AbstractPartialFunction.scala:36) [scala-library-2.11.6.jar:na]
    at scala.util.Failure$$anonfun$recover$1.apply(Try.scala:215) [scala-library-2.11.6.jar:na]
    at scala.util.Try$.apply(Try.scala:191) [scala-library-2.11.6.jar:na]
    at scala.util.Failure.recover(Try.scala:215) [scala-library-2.11.6.jar:na]
    at scala.concurrent.Future$$anonfun$recover$1.apply(Future.scala:324) [scala-library-2.11.6.jar:na]
    at scala.concurrent.Future$$anonfun$recover$1.apply(Future.scala:324) [scala-library-2.11.6.jar:na]
    at scala.concurrent.impl.CallbackRunnable.run(Promise.scala:32) [scala-library-2.11.6.jar:na]
    at play.api.libs.iteratee.Execution$trampoline$.executeScheduled(Execution.scala:109) [play-iteratees_2.11-2.4.4.jar:2.4.4]
    at play.api.libs.iteratee.Execution$trampoline$.execute(Execution.scala:71) [play-iteratees_2.11-2.4.4.jar:2.4.4]
    at scala.concurrent.impl.CallbackRunnable.executeWithValue(Promise.scala:40) [scala-library-2.11.6.jar:na]
    at scala.concurrent.impl.Promise$DefaultPromise.tryComplete(Promise.scala:248) [scala-library-2.11.6.jar:na]
    at scala.concurrent.Promise$class.complete(Promise.scala:55) [scala-library-2.11.6.jar:na]
    at scala.concurrent.impl.Promise$DefaultPromise.complete(Promise.scala:153) [scala-library-2.11.6.jar:na]
    at scala.concurrent.impl.Future$PromiseCompletingRunnable.run(Future.scala:23) [scala-library-2.11.6.jar:na]
    at akka.dispatch.TaskInvocation.run(AbstractDispatcher.scala:40) [akka-actor_2.11-2.3.13.jar:na]
    at akka.dispatch.ForkJoinExecutorConfigurator$AkkaForkJoinTask.exec(AbstractDispatcher.scala:397) [akka-actor_2.11-2.3.13.jar:na]
    at scala.concurrent.forkjoin.ForkJoinTask.doExec(ForkJoinTask.java:260) [scala-library-2.11.6.jar:na]
    at scala.concurrent.forkjoin.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1339) [scala-library-2.11.6.jar:na]
    at scala.concurrent.forkjoin.ForkJoinPool.runWorker(ForkJoinPool.java:1979) [scala-library-2.11.6.jar:na]
    at scala.concurrent.forkjoin.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:107) [scala-library-2.11.6.jar:na]
Caused by: java.lang.NullPointerException: null
    at com.avaje.ebean.Model$Find.query(Model.java:547) ~[avaje-ebeanorm-4.6.2.jar:na]
    at com.avaje.ebean.Model$Find.where(Model.java:741) ~[avaje-ebeanorm-4.6.2.jar:na]
    at repositories.AuthRepository.getAuthorizationQuery(AuthRepository.java:12) ~[classes/:na]
    at interceptors.AuthInterceptor.call(AuthInterceptor.java:31) ~[classes/:na]
    at play.core.j.JavaAction$$anonfun$7.apply(JavaAction.scala:94) ~[play_2.11-2.4.4.jar:2.4.4]
    at play.core.j.JavaAction$$anonfun$7.apply(JavaAction.scala:94) ~[play_2.11-2.4.4.jar:2.4.4]
    at scala.concurrent.impl.Future$PromiseCompletingRunnable.liftedTree1$1(Future.scala:24) [scala-library-2.11.6.jar:na]
    at scala.concurrent.impl.Future$PromiseCompletingRunnable.run(Future.scala:24) [scala-library-2.11.6.jar:na]
    at play.core.j.HttpExecutionContext$$anon$2.run(HttpExecutionContext.scala:40) ~[play_2.11-2.4.4.jar:2.4.4]
    at play.api.libs.iteratee.Execution$trampoline$.execute(Execution.scala:70) [play-iteratees_2.11-2.4.4.jar:2.4.4]
    at play.core.j.HttpExecutionContext.execute(HttpExecutionContext.scala:32) ~[play_2.11-2.4.4.jar:2.4.4]
    at scala.concurrent.impl.Future$.apply(Future.scala:31) ~[scala-library-2.11.6.jar:na]
    at scala.concurrent.Future$.apply(Future.scala:492) ~[scala-library-2.11.6.jar:na]
    at play.core.j.JavaAction.apply(JavaAction.scala:94) ~[play_2.11-2.4.4.jar:2.4.4]
    at play.api.mvc.Action$$anonfun$apply$1$$anonfun$apply$4$$anonfun$apply$5.apply(Action.scala:105) ~[play_2.11-2.4.4.jar:2.4.4]
    at play.api.mvc.Action$$anonfun$apply$1$$anonfun$apply$4$$anonfun$apply$5.apply(Action.scala:105) ~[play_2.11-2.4.4.jar:2.4.4]
    at play.utils.Threads$.withContextClassLoader(Threads.scala:21) ~[play_2.11-2.4.4.jar:2.4.4]
    at play.api.mvc.Action$$anonfun$apply$1$$anonfun$apply$4.apply(Action.scala:104) ~[play_2.11-2.4.4.jar:2.4.4]
    at play.api.mvc.Action$$anonfun$apply$1$$anonfun$apply$4.apply(Action.scala:103) ~[play_2.11-2.4.4.jar:2.4.4]
    at scala.Option.map(Option.scala:146) ~[scala-library-2.11.6.jar:na]
    at play.api.mvc.Action$$anonfun$apply$1.apply(Action.scala:103) ~[play_2.11-2.4.4.jar:2.4.4]
    at play.api.mvc.Action$$anonfun$apply$1.apply(Action.scala:96) ~[play_2.11-2.4.4.jar:2.4.4]
    at play.api.libs.iteratee.Iteratee$$anonfun$mapM$1.apply(Iteratee.scala:524) ~[play-iteratees_2.11-2.4.4.jar:2.4.4]
    at play.api.libs.iteratee.Iteratee$$anonfun$mapM$1.apply(Iteratee.scala:524) ~[play-iteratees_2.11-2.4.4.jar:2.4.4]
    at play.api.libs.iteratee.Iteratee$$anonfun$flatMapM$1.apply(Iteratee.scala:560) ~[play-iteratees_2.11-2.4.4.jar:2.4.4]
    at play.api.libs.iteratee.Iteratee$$anonfun$flatMapM$1.apply(Iteratee.scala:560) ~[play-iteratees_2.11-2.4.4.jar:2.4.4]
    at play.api.libs.iteratee.Iteratee$$anonfun$flatMap$1$$anonfun$apply$13.apply(Iteratee.scala:536) ~[play-iteratees_2.11-2.4.4.jar:2.4.4]
    at play.api.libs.iteratee.Iteratee$$anonfun$flatMap$1$$anonfun$apply$13.apply(Iteratee.scala:536) ~[play-iteratees_2.11-2.4.4.jar:2.4.4]
    at scala.concurrent.impl.Future$PromiseCompletingRunnable.liftedTree1$1(Future.scala:24) [scala-library-2.11.6.jar:na]
    at scala.concurrent.impl.Future$PromiseCompletingRunnable.run(Future.scala:24) [scala-library-2.11.6.jar:na]
    ... 6 common frames omitted

Answer 1

如果有人遇到类似的问题，应该仔细检查配置。默认的 Model 父类(super class)不关心它。有关 aplication.conf 和 orm.xml 的详细信息可以在此处找到:

EBean config