Question

我正在尝试测试java应用程序（有主要方法）。我正在使用maven将依赖项添加到我的项目中。我直接从IntelliJ IDE运行应用程序，而不是创建一个胖jar然后运行。但不知何故，我无法在运行时找到JSON类并获得异常

Exception in thread "main"
java.lang.NoClassDefFoundError: com/fasterxml/jackson/databind/ObjectMapper
at com.hospitality.component.visma.websocket.Test.<init>(Test.java:10)
at com.hospitality.component.visma.websocket.Test.main(Test.java:16)
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:497)
at com.intellij.rt.execution.application.AppMain.main(AppMain.java:147)
Caused by: java.lang.ClassNotFoundException: com.fasterxml.jackson.databind.ObjectMapper

这是我的pom.xml：

     <dependency>
       <groupId>com.fasterxml.jackson.jaxrs</groupId>
       <artifactId>jackson-jaxrs-json-provider</artifactId>
     </dependency>

这个项目有一个父pom.xml文件，它已经包含了这个jar.mvn dependecy：树，显示了以下jar列表：

[INFO] Building visma-websocket-server 0.0.1-SNAPSHOT
[INFO] -----------------------------------------------------------
  -------------
[INFO] 
[INFO] --- maven-dependency-plugin:2.1:tree (default-cli) @ visma-websocket-server ---
[INFO] com.hospitality.hp.components:visma-websocket-server:jar:0.0.1-SNAPSHOT
[INFO] +- org.glassfish.metro:webservices-rt:jar:2.3:provided
[INFO] |  \- org.glassfish.metro:webservices-api:jar:2.3:provided
[INFO] |     \- javax.annotation:javax.annotation-api:jar:1.2-b03:provided
[INFO] +- junit:junit:jar:4.11:test
[INFO] |  \- org.hamcrest:hamcrest-core:jar:1.3:test
[INFO] +- org.hamcrest:hamcrest-all:jar:1.3:test
[INFO] +- javax:javaee-api:jar:7.0:provided
[INFO] |  \- com.sun.mail:javax.mail:jar:1.5.0:provided
[INFO] |     \- javax.activation:activation:jar:1.1:provided
[INFO] +- org.slf4j:slf4j-api:jar:1.7.21:compile
[INFO] +- ch.qos.logback:logback-classic:jar:1.1.7:compile
[INFO] |  \- ch.qos.logback:logback-core:jar:1.1.7:compile
[INFO] +- org.eclipse.jetty.websocket:websocket-server:jar:9.0.3.v20130506:compile
[INFO] |  +- org.eclipse.jetty.websocket:websocket-common:jar:9.0.3.v20130506:compile
[INFO] |  |  +- org.eclipse.jetty.websocket:websocket-api:jar:9.0.3.v20130506:compile
[INFO] |  |  \- org.eclipse.jetty:jetty-util:jar:9.0.3.v20130506:compile
[INFO] |  +- org.eclipse.jetty.websocket:websocket-servlet:jar:9.0.3.v20130506:compile
[INFO] |  \- org.eclipse.jetty:jetty-http:jar:9.0.3.v20130506:compile
[INFO] +- com.hospitality.hp.components:jndi-tools:jar:0.0.1-SNAPSHOT:compile
[INFO] +- org.eclipse.jetty:jetty-server:jar:9.0.3.v20130506:compile
[INFO] |  +- org.eclipse.jetty.orbit:javax.servlet:jar:3.0.0.v201112011016:compile
[INFO] |  \- org.eclipse.jetty:jetty-io:jar:9.0.3.v20130506:compile
[INFO] +- com.fasterxml.jackson.jaxrs:jackson-jaxrs-json-provider:jar:2.2.1:provided
[INFO] |  +- com.fasterxml.jackson.jaxrs:jackson-jaxrs-base:jar:2.2.1:provided
[INFO] |  +- com.fasterxml.jackson.core:jackson-core:jar:2.2.1:provided
[INFO] |  +- com.fasterxml.jackson.core:jackson-databind:jar:2.2.1:provided
[INFO] |  |  \- com.fasterxml.jackson.core:jackson-annotations:jar:2.2.1:provided
[INFO] |  \- com.fasterxml.jackson.module:jackson-module-jaxb-annotations:jar:2.2.1:provided
[INFO] \- org.projectlombok:lombok:jar:1.16.8:provided

有人可以告诉我如何解决这个问题，因为默认范围是编译，所以当我在IDE中运行我的应用程序时，为什么这不可用？但是在JunitTest中没有任何问题。知道如何解决这个问题吗？

------------------------- dependencyManagement --------------------- ------------

<dependencyManagement>
    <dependencies>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-annotations</artifactId>
            <scope>compile</scope>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
            <scope>compile</scope>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-core</artifactId>
            <scope>compile</scope>
        </dependency>
    </dependencies>
</dependencyManagement>

Answer 1

|  +- com.fasterxml.jackson.core:jackson-databind:jar:2.2.1:provided

范围为provided，因此NoClassDefFoundError是正常的;应该省略范围说明并使用默认值。

杰克逊提供商在运行应用程序时不可用

1 个答案: