proguard

pom.xml

<build>
    <plugins>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-shade-plugin</artifactId>
            <executions>
                <execution>
                    <phase>package</phase>
                    <goals><goal>shade</goal></goals>
                </execution>
            </executions>
            <configuration>
                <artifactSet>
                    <includes>
                        <include>com.yourcompany.*:*</include>
                    </includes>

                    <!--
                        maven-shade-plugin experiences issues shading dlls.
                        Unfortunately, our application has several.
                        You could also place some modules you don't want obfuscate.
                    -->
                    <excludes>
                        <exclude>com.yourcompany:native-library</exclude>
                        <exclude>com.yourcompany:another-native-library</exclude>
                    </excludes>
                </artifactSet>

                <transformers>
                    <transformer implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">

                        <!-- This is entry point of your jar -->
                        <mainClass>com.yourcompany.Main</mainClass>
                    </transformer>
                </transformers>
            </configuration>
        </plugin>
        <plugin>
          <groupId>com.github.wvengen</groupId>
          <artifactId>proguard-maven-plugin</artifactId>
          <executions>
              <execution>
                  <phase>package</phase>
                  <goals><goal>proguard</goal></goals>
              </execution>
          </executions>
          <configuration>
              <!-- Our application is so big that ProGuard had ran out of memory -->
              <maxMemory>1024m</maxMemory>
      
              <!-- File with proguard configuration -->
              <proguardInclude>${basedir}/proguard.conf</proguardInclude>
      
              <!-- Now exclude all modules that are embedded in the jar, so that
                  ProGuard won't see redefinition of each single class.
                  You don't have to write down your main module. -->
              <exclusions>
                  <exclusion>
                      <groupId>com.yourcompany</groupId>
                      <artifactId>data</artifactId>
                  </exclusion>
      
                  <!-- And so on -->
              </exclusions>
      
              <!--
                  List external jars your application depends on
                  (that not listed in maven dependencies).
                  You probably depend on jave runtime (rt.jar).
      
                  JCE stands for Java Cryptography Extension.
                  You probably don't need it, but my application does.
              -->
              <libs>
                  <lib>${java.home}/lib/rt.jar</lib>
                  <lib>${java.home}/lib/jce.jar</lib>
                  <lib>${java.home}/lib/ext/sunjce_provider.jar</lib>
              </libs>
          </configuration>
      </plugin>
    </plugins>
</build>

Proguard example

-optimizationpasses 5
-dontusemixedcaseclassnames
-dontskipnonpubliclibraryclasses
-dontpreverify
-verbose

-keep, allowobfuscation class be.ogregoire.*
-keepclassmembers, allowobfuscation class * {
    *;
}


-keepnames class be.ogregoire.MyClass
-keepclassmembernames class be.ogregoire.MyClass {
    public <methods>;
    public <fields>;
}