sudo apt-get purge jre
Reading package lists... Done
Building dependency tree
Reading state information... Done
Package 'jre' is not installed, so not removed
0 to upgrade, 0 to newly install, 0 to remove and 0 not to upgrade.
1 not fully installed or removed.
After this operation, 0 B of additional disk space will be used.
Setting up jre1.8.0-101 (1.8.0101-1) ...
Unpacking JAR files...
        plugin.jar...
Error: Could not open input file: /usr/java/jre1.8.0_101/lib/plugin.pack
        javaws.jar...
Error: Could not open input file: /usr/java/jre1.8.0_101/lib/javaws.pack
        deploy.jar...
Error: Could not open input file: /usr/java/jre1.8.0_101/lib/deploy.pack
        rt.jar...
Error: Could not open input file: /usr/java/jre1.8.0_101/lib/rt.pack
        jsse.jar...
Error: Could not open input file: /usr/java/jre1.8.0_101/lib/jsse.pack
        charsets.jar...
Error: Could not open input file: /usr/java/jre1.8.0_101/lib/charsets.pack
        localedata.jar...
Error: Could not open input file: /usr/java/jre1.8.0_101/lib/ext/localedata.pack
/var/lib/dpkg/info/jre1.8.0-101.postinst: line 641: /usr/sbin/alternatives: No such file or directory
dpkg: error processing package jre1.8.0-101 (--configure):
 subprocess installed post-installation script returned error exit status 127
Errors were encountered while processing:
 jre1.8.0-101
E: Sub-process /usr/bin/dpkg returned an error code (1)