Why does relocation with the maven shade plugin not work?

Question

I am having some trouble running a Hadoop job that includes a newer version of Guava than the one that is included in the Hadoop distribution (CDH 5.2). This is a known problem. I try to solve it by shading the libraries using the Maven shade plugin. Therefore, I added the following lines to my pom.xml:

  <plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-shade-plugin</artifactId>
    <version>2.3</version>
    <executions>
      <execution>
        <phase>package</phase>
        <goals>
          <goal>shade</goal>
        </goals>
        <configuration>
          <relocations>
            <relocation>
              <pattern>com.google</pattern>
              <shadedPattern>thirdparty.com.google</shadedPattern>
            </relocation>
          </relocations>
        </configuration>
      </execution>
    </executions>
  </plugin>

Unfortunately, the shading seems not to work. When I extract the uber-JAR there is no folder thirdparty/com/google but still the folder com/google.

Does someone have an idea what is going wrong?

it is avaibable for me, you can try it again then check the generated jar whether it takes effect.
com.google shade.com.google — Jiayu Wang, May 07 '20 at 09:12

score 13 · Answer 1 · answered Apr 12 '17 at 03:17

13

This worked for me:

<relocations>
   <relocation>
     <pattern>com.google.</pattern>
     <shadedPattern>thirdparty.com.google.</shadedPattern>
   </relocation>
 </relocations>

note the dot at the end of the pattern.

answered Apr 12 '17 at 03:17

wcolen

1,401
10
15

How would one import this within a .scala file? import thirdparty.com.google. does not work for me. – Rorschach Dec 29 '20 at 05:42

score 4 · Answer 2 · answered Dec 18 '14 at 18:35

4

You may need to specify explicit artifactSet::includes under your <configuration> section:

    <configuration>
        <artifactSet>
            <includes>
                <include>com.google.guava:*</include>
                ...
            </includes>
        </artifactSet>
        <relocations>
        ...

answered Dec 18 '14 at 18:35

Dennis Huo

10,517
27
43

Doing this requires you to then specify every inclusion. It also did not fix the shading issue. – AaronM Oct 06 '16 at 22:58
An empty `` made it work for me. – user1639030 Jun 21 '23 at 22:32

score 3 · Answer 3 · answered May 26 '17 at 21:52

Seems like you need to refer to the package name in the relocation rule, not the maven groupId, I'm using rx v1 in my lib and don't want to pollute the user's namespace with it, the pom.xml section below rewrites the bytecode, so the final uberjar will have rx, but renamed (shaded.rx).

shade relocation doc

<plugin>
  <groupId>org.apache.maven.plugins</groupId>
  <artifactId>maven-shade-plugin</artifactId>
  <version>3.0.0</version>
  <executions>
    <execution>
      <phase>package</phase>
        <goals>
          <goal>shade</goal>
        </goals>
        <configuration>
          <relocations>
            <relocation>
              <pattern>rx</pattern>
              <shadedPattern>shaded.rx</shadedPattern>
            </relocation>
          </relocations>
        </configuration>
      </execution>
    </executions>
  </plugin>

Why does relocation with the maven shade plugin not work?

3 Answers3

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