Bug#895885: freeplane does not start up without (exactly) java 9

[Raphael Wimmer]

Package: freeplane
Version: 1.6.13-1
Severity: important

Dear Maintainers,

Freeplane will not start up if a user has not installed the Java 9
JRE, providing the error message:

> [...]
> Exception in thread "main" java.lang.UnsupportedClassVersionError: org/knopflerfish/framework/Main has been compiled by a more recent version of the Java Runtime (class file version 53.0), this version of the Java Runtime only recognizes class file versions up to 52.0
> [...]

It seems that recent knopflerfish packages are getting compiled with
Java 9 (class file version 53). 
However, `/usr/bin/freeplane` only asks for at least Java 7 (line 125):

> require_java_runtime java7

As the java-wrappers package only knows about Java versions up to Java
9 at the moment [1], having Java 10 or 11 installed does not help as
java-wrappers will never look for them.

Workaround: 
Users can still start up freeplane with the following command if they have
installed (and set as default) at least a Java 9 JRE:

> JAVA_CMD=/usr/bin/java freeplane

All the best,
Raphael

[1] https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=895884

-- Package-specific info:
[debug] /usr/bin/freeplane: Found JAVA_HOME = '/usr/lib/jvm/java-8-openjdk-amd64'
[debug] /usr/bin/freeplane: Found JAVA_CMD = '/usr/lib/jvm/java-8-openjdk-amd64/bin/java'
DEBUG:   Freeplane parameters are ''.
DEBUG:   Linux anywhere 4.16.0-trunk-amd64 #1 SMP Debian 4.16-1~exp1 (2018-04-08) x86_64 GNU/Linux
No LSB modules are available.
DEBUG:   Distributor ID:	Debian
Description:	Debian GNU/Linux testing (buster)
Release:	testing
Codename:	buster
DEBUG:   The following DEB packages are installed:
ii  freeplane                   1.6.13-1           all                Java program for working with Mind Maps
DEBUG:   Link '/usr/bin/freeplane' resolved to '/usr/share/freeplane/freeplane.sh'.
DEBUG:   Freeplane Directory is '/usr/share/freeplane'.
DEBUG:   Calling: /usr/lib/jvm/java-8-openjdk-amd64/bin/java
         -Xmx512m
         -Dorg.freeplane.basedirectory=/usr/share/freeplane
         -Dorg.freeplane.userfpdir=/home/raphael/.config/freeplane
         -Dorg.freeplane.old_userfpdir=/home/raphael/.freeplane
         -Dorg.freeplane.globalresourcedir=/usr/share/freeplane/resources
         -Dswing.systemlaf=javax.swing.plaf.metal.MetalLookAndFeel
         -Dorg.freeplane.os.lib.ext=/usr/share/java
         -Dawt.useSystemAAFontSettings=on
         -Dswing.aatext=true
         -Dgnu.java.awt.peer.gtk.Graphics=Graphics2D
         -jar
         /usr/share/freeplane/freeplanelauncher.jar

-- System Information:
Debian Release: buster/sid
  APT prefers testing
  APT policy: (990, 'testing'), (500, 'unstable'), (1, 'experimental')
Architecture: amd64 (x86_64)

Kernel: Linux 4.16.0-trunk-amd64 (SMP w/4 CPU cores)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8), LANGUAGE=en_US:en (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled

Versions of packages freeplane depends on:
ii  default-jre [java7-runtime]          2:1.8-59
ii  groovy                               2.4.15-1
ii  javahelp2                            2.0.05.ds1-9
ii  jmapviewer                           2.7+dfsg-1
ii  libavalon-framework-java             4.2.0-10
ii  libbatik-java                        1.9-3
ii  libcommons-codec-java                1.11-1
ii  libcommons-io-java                   2.6-2
ii  libcommons-lang-java                 2.6-8
ii  libcommons-logging-java              1.2-2
ii  libfop-java                          1:2.1-7
ii  libidw-java                          1.6.1-1
ii  libjaxp1.3-java                      1.3.05-5
ii  libjgoodies-forms-java               1.9.0-3
ii  libjlatexmath-java                   1.0.6-1
ii  libjsyntaxpane-java                  0.9.6~r156-6
ii  libknopflerfish-osgi-framework-java  6.1.1-2
ii  libmnemonicsetter-java               0.5-1
ii  librhino-java                        1.7.7.1-1
ii  libsvgsalamander-java                1.1.1+dfsg-2
ii  libxerces2-java                      2.11.0-8
ii  libxml-commons-external-java         1.4.01-3
ii  libxmlgraphics-commons-java          2.2-1
ii  openjdk-11-jre [java7-runtime]       11~9-1
ii  openjdk-8-jre [java7-runtime]        8u162-b12-1
ii  simplyhtml                           0.17.3+dfsg1-1

Versions of packages freeplane recommends:
ii  java-wrappers  0.2
ii  xdg-utils      1.1.2-2

Versions of packages freeplane suggests:
pn  freeplane-scripting-api  <none>

-- no debconf information