maven shade解决storm Elasticsearch log4j jar包版本冲突

新建一个maven简单工程即可，该工程的目的是将es、log4j等jar包里的class文件重新打包，全部放入到一个jar包里，再放入的过程中将所有“org.apache.logging.log4j”开头的报名改为“my.elasticsearch.log4j”，也就相当于将import log4j的地方统统改了，这样就相当于第三方编写的log4j，pom.xml如下：

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
	<modelVersion>4.0.0</modelVersion>
	<groupId>my.elasticsearch.test</groupId>
	<artifactId>es-shaded</artifactId>
	<version>1.0-SNAPSHOT</version>
	<properties>
		<elasticsearch.version>5.2.2</elasticsearch.version>
	</properties>
	<dependencies>
		<dependency>
			<groupId>org.elasticsearch</groupId>
			<artifactId>elasticsearch</artifactId>
			<version>${elasticsearch.version}</version>
		</dependency>
		<dependency>
			<groupId>org.elasticsearch.client</groupId>
			<artifactId>transport</artifactId>
			<version>${elasticsearch.version}</version>
		</dependency>
		<dependency>
			<groupId>org.apache.logging.log4j</groupId>
			<artifactId>log4j-core</artifactId>
			<version>2.7</version>
		</dependency>
		<dependency>
			<groupId>org.slf4j</groupId>
			<artifactId>log4j-over-slf4j</artifactId>
			<version>1.7.7</version>
		</dependency>
	</dependencies>
	<build>
		<plugins>
			<plugin>
				<groupId>org.apache.maven.plugins</groupId>
				<artifactId>maven-shade-plugin</artifactId>
				<version>2.4.1</version>
				<executions>
					<execution>
						<phase>package</phase>
						<goals>
							<goal>shade</goal>
						</goals>
						<configuration>
							<relocations>
								<relocation>
									<pattern>org.apache.logging.log4j</pattern>
									<shadedPattern>my.elasticsearch.log4j</shadedPattern>
								</relocation>
							</relocations>
							<transformers>
								<transformer
									implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer" />
							</transformers>
						</configuration>
					</execution>
				</executions>
			</plugin>
		</plugins>
	</build>
</project>

运行mvn clean install
将打包好的jar包安装到本地，验证效果如下图：

最后在自己的工程里，引入新的jar包即可，不需要额外引入es和log4j的jar包了。