这是一个jar包冲突引起的Java程序错误，而且是runtime的错误，编译的时候不出错，一运行起来就挂。
大致的错误信息如下：
Thread[main,5,main] exit with uncaught error java.lang.SecurityException: class "javax.servlet.FilterRegistration"'s signer information does not match signer information of other classes in the same package
java.lang.SecurityException: class "javax.servlet.FilterRegistration"'s signer information does not match signer information of other classes in the same package
at java.lang.ClassLoader.checkCerts(ClassLoader.java:895)
at java.lang.ClassLoader.preDefineClass(ClassLoader.java:665)
at java.lang.ClassLoader.defineClass(ClassLoader.java:758)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:467)
at java.net.URLClassLoader.access$100(URLClassLoader.java:73)
at java.net.URLClassLoader$1.run(URLClassLoader.java:368)
at java.net.URLClassLoader$1.run(URLClassLoader.java:362)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:361)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
网上一搜就知道，这是jar包冲突引起的，也就是说，classpath中的两个版本不同的jar包都含有FilterRegistration类的实现，并且它们不兼容。
那为什么会产生冲突呢？虽然你的pom.xml文件（Maven的工程）里只包含有一个javax-servlet-api的依赖，但是有其他的jar包会间接依赖于其他版本的 servlet-api，从而可能会产生冲突。
为了找出这个冲突的jar包，你可以使用IntelliJ IDEA的Maven插件 Maven Helper 来帮忙，或者你不愿装新插件的话，直接用如下命令来导出各jar包的依赖关系：
mvn dependency:tree > dependency.txt
在这里，我把结果输出到了一个文件 x.txt 中，内容类似于（仅部分）：
[INFO] +- org.apache.hadoop:hadoop-client:jar:2.6.0:compile [INFO] | +- org.apache.hadoop:hadoop-common:jar:2.6.0:compile [INFO] | | +- commons-cli:commons-cli:jar:1.2:compile [INFO] | | +- xmlenc:xmlenc:jar:0.52:compile [INFO] | | +- commons-collections:commons-collections:jar:3.2.1:compile [INFO] | | +- commons-configuration:commons-configuration:jar:1.6:compile [INFO] | | | +- commons-digester:commons-digester:jar:1.8:compile [INFO] | | | | \- commons-beanutils:commons-beanutils:jar:1.7.0:compile [INFO] | | | \- commons-beanutils:commons-beanutils-core:jar:1.8.0:compile [INFO] | | +- org.codehaus.jackson:jackson-core-asl:jar:1.9.13:compile [INFO] | | +- com.google.code.gson:gson:jar:2.2.4:compile [INFO] | | +- org.apache.curator:curator-client:jar:2.6.0:compile [INFO] | | +- org.htrace:htrace-core:jar:3.0.4:compile [INFO] | | \- org.apache.commons:commons-compress:jar:1.4.1:compile [INFO] | | \- org.tukaani:xz:jar:1.0:compile [INFO] | +- org.apache.hadoop:hadoop-hdfs:jar:2.6.0:compile [INFO] | | +- org.mortbay.jetty:jetty-util:jar:6.1.26:compile [INFO] | | +- io.netty:netty:jar:3.6.2.Final:compile [INFO] | | \- xerces:xercesImpl:jar:2.9.1:compile [INFO] | | \- xml-apis:xml-apis:jar:1.3.04:compile [INFO] | +- org.apache.hadoop:hadoop-mapreduce-client-app:jar:2.6.0:compile [INFO] | | +- org.apache.hadoop:hadoop-mapreduce-client-common:jar:2.6.0:compile [INFO] | | | +- org.apache.hadoop:hadoop-yarn-client:jar:2.6.0:compile [INFO] | | | \- org.apache.hadoop:hadoop-yarn-server-common:jar:2.6.0:compile [INFO] | | \- org.apache.hadoop:hadoop-mapreduce-client-shuffle:jar:2.6.0:compile [INFO] | +- org.apache.hadoop:hadoop-yarn-api:jar:2.6.0:compile [INFO] | +- org.apache.hadoop:hadoop-mapreduce-client-core:jar:2.6.0:compile [INFO] | | \- org.apache.hadoop:hadoop-yarn-common:jar:2.6.0:compile [INFO] | | +- javax.xml.bind:jaxb-api:jar:2.2.2:compile [INFO] | | | +- javax.xml.stream:stax-api:jar:1.0-2:compile [INFO] | | | \- javax.activation:activation:jar:1.1:compile [INFO] | | +- javax.servlet:servlet-api:jar:2.5:compile [INFO] | | +- com.sun.jersey:jersey-client:jar:1.9:compile [INFO] | | +- org.codehaus.jackson:jackson-jaxrs:jar:1.9.13:compile [INFO] | | \- org.codehaus.jackson:jackson-xc:jar:1.9.13:compile [INFO] | +- org.apache.hadoop:hadoop-mapreduce-client-jobclient:jar:2.6.0:compile [INFO] | \- org.apache.hadoop:hadoop-annotations:jar:2.6.0:compile [INFO] +- org.apache.spark:spark-core_2.10:jar:1.6.0:provided [INFO] | +- org.apache.avro:avro-mapred:jar:hadoop2:1.7.7:provided [INFO] | | +- org.apache.avro:avro-ipc:jar:1.7.7:compile [INFO] | | \- org.apache.avro:avro-ipc:jar:tests:1.7.7:provided [INFO] | +- com.twitter:chill_2.10:jar:0.5.0:compile [INFO] | | \- com.esotericsoftware.kryo:kryo:jar:2.21:compile [INFO] | | +- com.esotericsoftware.reflectasm:reflectasm:jar:shaded:1.07:compile [INFO] | | +- com.esotericsoftware.minlog:minlog:jar:1.2:compile [INFO] | | \- org.objenesis:objenesis:jar:1.2:compile [INFO] | +- com.twitter:chill-java:jar:0.5.0:compile [INFO] | +- org.apache.xbean:xbean-asm5-shaded:jar:4.4:provided [INFO] | +- org.apache.spark:spark-launcher_2.10:jar:1.6.0:provided [INFO] | +- org.apache.spark:spark-network-common_2.10:jar:1.6.0:provided [INFO] | +- org.apache.spark:spark-network-shuffle_2.10:jar:1.6.0:provided [INFO] | | +- org.fusesource.leveldbjni:leveldbjni-all:jar:1.8:compile [INFO] | | \- com.fasterxml.jackson.core:jackson-annotations:jar:2.4.4:compile [INFO] | +- org.apache.spark:spark-unsafe_2.10:jar:1.6.0:compile [INFO] | +- net.java.dev.jets3t:jets3t:jar:0.7.1:provided [INFO] | +- org.apache.curator:curator-recipes:jar:2.4.0:compile [INFO] | | \- org.apache.curator:curator-framework:jar:2.4.0:compile [INFO] | +- org.eclipse.jetty.orbit:javax.servlet:jar:3.0.0.v201112011016:provided [INFO] | +- org.apache.commons:commons-lang3:jar:3.3.2:provided [INFO] | +- org.apache.commons:commons-math3:jar:3.4.1:compile
可见有两处用到 javax.servlet 而且版本不一致
于是我们需要在pom.xml中，视情况把不同版本的servlet-api给“除掉”，这里我选择的是除掉hadoop-common中的旧版本servlet-api：
<dependency> <groupId>org.apache.hadoop</groupId> <artifactId>hadoop-client</artifactId> <version>2.6.0</version> <exclusions> <exclusion> <groupId>javax.servlet</groupId> <artifactId>*</artifactId> </exclusion> </exclusions> </dependency>
重新打包使用或者直接运行。