Best way to get maven dependencies

Question

I just need to use this org.apache.commons.io.FileUtils class, and yet I am loading all the public classes that I really don't need, is there any way to tell that maven only loads the FileUtils class? Not whole domains, as depending on the dependency below

<dependency>
   <groupId>commons-io</groupId>
   <artifactId>commons-io</artifactId>
   <version>1.4</version>
</dependency>

Answer 1

is there any way to tell maven to download only the FileUtils class?

No. But depending on your specific use case, you can use Maven Shade Plugin to create uber-jar and filter the contents of included dependencies

Content Selection for Uber JAR

...

, :

<project>
  ... 
  <build>
    <plugins>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-shade-plugin</artifactId>
        <version>1.3.3</version>
        <executions>
          <execution>
            <phase>package</phase>
            <goals>
              <goal>shade</goal>
            </goals>
            <configuration>
              <filters>
                <filter>
                  <artifact>junit:junit</artifact>
                  <includes>
                    <include>junit/framework/**</include>
                    <include>org/junit/**</include>
                  </includes>
                  <excludes>
                    <exclude>org/junit/experimental/**</exclude>
                    <exclude>org/junit/runners/**</exclude>
                  </excludes>
                </filter>
                <filter>
                  <artifact>*:*</artifact>
                  <excludes>
                    <exclude>META-INF/*.SF</exclude>
                    <exclude>META-INF/*.DSA</exclude>
                    <exclude>META-INF/*.RSA</exclude>
                  </excludes>
                </filter>
              </filters>
            </configuration>
          </execution>
        </executions>
      </plugin>
    </plugins>
  </build>
  ...
</project>

Ant - , junit: junit / uber JAR. , 1.3 . , , .

, FileUtils :

import org.apache.commons.io.filefilter.DirectoryFileFilter;
import org.apache.commons.io.filefilter.FalseFileFilter;
import org.apache.commons.io.filefilter.FileFilterUtils;
import org.apache.commons.io.filefilter.IOFileFilter;
import org.apache.commons.io.filefilter.SuffixFileFilter; // depends on org.apache.commons.io.IOCase
import org.apache.commons.io.filefilter.TrueFileFilter;
import org.apache.commons.io.output.NullOutputStream;

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Answer 2

Apache commons io apache. io, . 100 , .

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FileUtils io. !

Answer 3

<exclusion>

    <dependency>
      <groupId>sample.ProjectA</groupId>
      <artifactId>Project-A</artifactId>
      <version>1.0</version>
      <scope>compile</scope>
      <exclusions>
        <exclusion>  <!-- declare the exclusion here -->
          <groupId>sample.ProjectB</groupId>
          <artifactId>Project-B</artifactId>
        </exclusion>
      </exclusions> 
    </dependency>

, .

mvn dependency:analyze-only mvn dependecy:tree, , , , / .

.

Answer 4

. jar; ( ). , .

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