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How can I change the default (in my case SHA256) digest algorithm within the configuration of maven-jarsigner-plugin? I would like it to be SHA1. I tried adding <digestalg>SHA1</digestalg> to the configuration block in the pom but that didn't do it because MANIFEST.MF still came out reporting SHA256.
In a command line, you would just do:
jarsigner ... -digestalg SHA1 myjar.jar myalias

As per this post, using arguments worked for me:
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-jarsigner-plugin</artifactId>
<version>1.4</version>
<executions>
<execution>
<phase>package</phase>
<id>sign</id>
<goals>
<goal>sign</goal>
</goals>
</execution>
</executions>
<configuration>
<keystore>mykey.jks</keystore>
<alias>myalias</alias>
<storepass>somepass</storepass>
<arguments>
<argument>-digestalg</argument><argument>SHA1</argument>
</arguments>
</configuration>
</plugin>