java.lang.NoClassDefFoundError: org/apache/kafka/common/security/auth/SecurityProtocol

在编写kafka操作API的过程中，查询的方法都没有什么问题，删除、修改topic或者消费组的时候，会出现一大堆红色报错：

java.lang.NoClassDefFoundError: org/apache/kafka/common/security/auth/SecurityProtocol

	at kafka.zk.BrokerIdZNode$.$anonfun$decode$3(ZkData.scala:213)
	at scala.collection.TraversableLike.$anonfun$map$1(TraversableLike.scala:234)
	at scala.collection.immutable.Map$Map1.foreach(Map.scala:120)
	at scala.collection.TraversableLike.map(TraversableLike.scala:234)
	at scala.collection.TraversableLike.map$(TraversableLike.scala:227)
	at scala.collection.AbstractTraversable.map(Traversable.scala:104)
	at kafka.zk.BrokerIdZNode$.$anonfun$decode$2(ZkData.scala:212)
	at scala.Option.map(Option.scala:146)
	at kafka.zk.BrokerIdZNode$.decode(ZkData.scala:212)
	at kafka.utils.ZkUtils.parseBrokerJson(ZkUtils.scala:708)
	at kafka.utils.ZkUtils.$anonfun$getCluster$1(ZkUtils.scala:702)
	at scala.collection.Iterator.foreach(Iterator.scala:929)
	at scala.collection.Iterator.foreach$(Iterator.scala:929)
	at scala.collection.AbstractIterator.foreach(Iterator.scala:1417)
	at scala.collection.IterableLike.foreach(IterableLike.scala:71)
	at scala.collection.IterableLike.foreach$(IterableLike.scala:70)
	at scala.collection.AbstractIterable.foreach(Iterable.scala:54)
	at kafka.utils.ZkUtils.getCluster(ZkUtils.scala:700)
	at com.sunline.channel.kafkaAPI.manager.ConsoleApi.getCluster(ConsoleApi.java:42)
	at com.sunline.channel.kafkaAPI.manager.ConsoleApiTest.getCluster(ConsoleApiTest.java:25)
	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.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
	at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
	at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
	at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
	at org.springframework.test.context.junit4.statements.RunBeforeTestMethodCallbacks.evaluate(RunBeforeTestMethodCallbacks.java:75)
	at org.springframework.test.context.junit4.statements.RunAfterTestMethodCallbacks.evaluate(RunAfterTestMethodCallbacks.java:86)
	at org.springframework.test.context.junit4.statements.SpringRepeat.evaluate(SpringRepeat.java:84)
	at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
	at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:252)
	at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:94)
	at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
	at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
	at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
	at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
	at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
	at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61)
	at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:70)
	at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
	at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:191)
	at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
	at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:68)
	at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:47)
	at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:242)
	at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:70)
Caused by: java.lang.ClassNotFoundException: org.apache.kafka.common.security.auth.SecurityProtocol
	at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
	at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:338)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
	... 48 more

我的pom依赖是这样的：

<dependency>
            <groupId>org.springframework.kafka</groupId>
            <artifactId>spring-kafka</artifactId>
            <version>1.1.0</version>
        </dependency>
        <dependency>
            <groupId>org.apache.kafka</groupId>
            <artifactId>kafka_2.12</artifactId>
            <version>1.1.0</version>
        </dependency>

在网上各种搜，很多答案都是缺少jar包，有的说是kafka版本要换回到0.8.2.2,当然这也是一种方案，姑且可以算作方案一。

但是我的整个项目的Kafka版本使用的是最新版本，包括发送，接收消息等功能。而且全局搜索了一下，是存在这个类的，只是不在该路径下而已。那么思索一下，系统加载这个类的方法肯定不是期望版本中的，那么。。。。。。。。。。。。。

对呀，很可能是jar包冲突！！！

于是查了maven依赖的Jar包，果然有个冲突：

那么，pom依赖变成如下所示：

<dependency>
			<groupId>org.springframework.kafka</groupId>
			<artifactId>spring-kafka</artifactId>
			 <version>1.1.0</version>
			<exclusions>
				<exclusion>
					<groupId>org.apache.kafka</groupId>
					<artifactId>kafka-clients</artifactId>
				</exclusion>
			</exclusions>
		</dependency>
		<dependency>
			<groupId>org.apache.kafka</groupId>
			<artifactId>kafka_2.12</artifactId>
			<version>1.1.0</version>
		</dependency>

解决冲突以后，再次执行，错误便消失了，删除修改操作轻松搞定~

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