Hello,
could someone please help me to understand why my Java snap is not able to play sounds? If I create a deb package with a custom runtime (jpackage), it works fine.
I am sharing the yml file:
name: fromgtog
version: '7.0.0'
summary: Clone ALL GitHub/Gitea/Local to GitHub/Gitea.
description: |
Helps to clone all repositories from GitHub on Gitea/Local and vice versa.
grade: stable
confinement: strict
base: core24
icon: snap/gui/icon.png
title: FromGtoG
website: https://andre-i.eu
issues: https://github.com/goto-eof
license: MIT
compression: xz
slots:
fromgtog-dbus:
interface: dbus
bus: session
name: it.es5.fromgtog.dbus
apps:
fromgtog:
environment:
LD_LIBRARY_PATH: $LD_LIBRARY_PATH:$SNAP_DESKTOP_RUNTIME/usr/lib/$CRAFT_ARCH_TRIPLET_BUILD_FOR/libproxy:$SNAP_DESKTOP_RUNTIME/usr/lib/$CRAFT_ARCH_TRIPLET_BUILD_FOR/gio/modules
command: executor
extensions: [ gnome ]
plugs:
- network
- x11
- browser-support
- unity7
- home
- desktop
- desktop-legacy
- removable-media
- wayland
- network-bind
- pulseaudio
- alsa
slots:
- fromgtog-dbus
platforms:
amd64:
build-on: [ amd64 ]
build-for: [ amd64 ]
arm64:
build-on: [ arm64 ]
build-for: [ arm64 ]
parts:
wrapper:
plugin: dump
source: snap/local
source-type: local
application:
plugin: maven
source: .
build-packages:
- openjdk-21-jdk
- maven
stage-packages:
- openjdk-21-jre
- glib-networking
- libgtk-3-0
- xdg-utils
override-prime: |
snapcraftctl prime
rm -vf usr/lib/jvm/java-*-openjdk-*64/lib/security/blacklisted.certs
Have a look here:
You need to set up a bit more config to get the Alsa → Pulse backend working.
You need this file somewhere in $SNAP, e.g., $SNAP/etc/asound.conf
pcm.!default {
type pulse
fallback "sysdefault"
hint {
show on
description "Default ALSA Output (currently PulseAudio Sound Server)"
}
}
ctl.!default {
type pulse
fallback "sysdefault"
}
You need these stage packages
- libasound2
- libasound2-plugins
You…
In summary, Java is attempting to use ALSA directly and whilst snap can support this, it’s better to use PulseAudio (which might also actually be Pipewire, to your snap, they’re one and the same).
So you need to configure the environment just a little to get the ALSA/Pulse wrapper going, which would be applicable to both Java but other platforms in the same position of only having ALSA support natively.
Thanks James for your response.
I have updated my yml file:
name: fromgtog
version: '7.0.0'
summary: Clone ALL GitHub/Gitea/Local to GitHub/Gitea.
description: |
Helps to clone all repositories from GitHub on Gitea/Local and vice versa.
grade: stable
confinement: strict
base: core24
icon: snap/gui/icon.png
title: FromGtoG
website: https://andre-i.eu
issues: https://github.com/goto-eof
license: MIT
compression: xz
slots:
fromgtog-dbus:
interface: dbus
bus: session
name: it.es5.fromgtog.dbus
apps:
fromgtog:
environment:
ALSA_CONFIG_PATH: $SNAP/etc/asound.conf
LD_LIBRARY_PATH: $LD_LIBRARY_PATH:$SNAP_DESKTOP_RUNTIME/usr/lib/$CRAFT_ARCH_TRIPLET_BUILD_FOR/libproxy:$SNAP_DESKTOP_RUNTIME/usr/lib/$CRAFT_ARCH_TRIPLET_BUILD_FOR/gio/modules
command: executor
extensions: [ gnome ]
plugs:
- network
- x11
- browser-support
- unity7
- home
- desktop
- desktop-legacy
- removable-media
- wayland
- network-bind
- pulseaudio
- alsa
slots:
- fromgtog-dbus
parts:
wrapper:
plugin: dump
source: snap/local
source-type: local
alsa-config:
plugin: dump
source: snap/audio/asound.conf
source-type: file
organize:
asound.conf: etc/asound.conf
prime:
- etc/asound.conf
application:
plugin: maven
source: .
build-packages:
- openjdk-21-jdk
- maven
stage-packages:
- openjdk-21-jre
- glib-networking
- libgtk-3-0
- xdg-utils
- libasound2
- libasound2-plugins
- alsa-utils
after:
- alsa-config
prime:
- etc/asound.conf
override-prime: |
snapcraftctl prime
rm -vf usr/lib/jvm/java-*-openjdk-*64/lib/security/blacklisted.certs
But i am still obtaining the same error:
No line matching interface Clip supporting format PCM_SIGNED unknown sample rate, 16 bit, stereo, 4 bytes/frame, big-endian is supported.
at java.desktop/javax.sound.sampled.AudioSystem.getLine(AudioSystem.java:423)
at java.desktop/javax.sound.sampled.AudioSystem.getClip(AudioSystem.java:459)
event if the .wav file is little-endian. I want to reaffirm that from itellij the sounds works fine.
Do you observe any denials in the logs (journal specifically) when the app attempts to play the file?
Out of curiosity, can you download a random mp3 file and try e.g.,
> snap run --shell fromgtog
> aplay $SNAP_REAL_HOME/test.mp3
This should be able to play the file and if it can’t, it suggests something more confinement related. If it can, then it suggests the problem is more specifically Java related, since aplay would use the same Alsa/Pulse wrappers when it’s set up correctly.
Alongside the logs above (which you can try getting using the snappy-debug snap, running in a second terminal window alongside you trying the above), it should hopefully help determine what’s going on.
Hello James, the result is the following:
> aplay success.wav
> aplay: command not found
I fixed a little bit the yml file, and succeed to have aplay working:
Unknown PCM sysdefault
aplay: main:834: audio open error: No such file or directory
The new version of the yml:
name: fromgtog
version: '7.0.0'
summary: Clone ALL GitHub/Gitea/Local to GitHub/Gitea.
description: |
Helps to clone all repositories from GitHub on Gitea/Local and vice versa.
grade: stable
confinement: strict
base: core24
icon: snap/gui/icon.png
title: FromGtoG
website: https://andre-i.eu
issues: https://github.com/goto-eof
license: MIT
compression: xz
slots:
fromgtog-dbus:
interface: dbus
bus: session
name: it.es5.fromgtog.dbus
apps:
fromgtog:
environment:
ALSA_CONFIG_PATH: $SNAP/etc/asound.conf
LD_LIBRARY_PATH: $LD_LIBRARY_PATH:$SNAP_DESKTOP_RUNTIME/usr/lib/$CRAFT_ARCH_TRIPLET_BUILD_FOR/libproxy:$SNAP_DESKTOP_RUNTIME/usr/lib/$CRAFT_ARCH_TRIPLET_BUILD_FOR/gio/modules
command: executor
extensions: [ gnome ]
plugs:
- network
- x11
- browser-support
- unity7
- home
- desktop
- desktop-legacy
- removable-media
- wayland
- network-bind
- pulseaudio
- alsa
- alsa-utils
slots:
- fromgtog-dbus
parts:
wrapper:
plugin: dump
source: snap/local
source-type: local
alsa-config:
plugin: dump
source: snap/local/asound.conf
source-type: file
organize:
asound.conf: etc/asound.conf
prime:
- etc/asound.conf
application:
plugin: maven
source: .
build-packages:
- openjdk-21-jdk
- maven
stage-packages:
- openjdk-21-jre
- glib-networking
- libgtk-3-0
- xdg-utils
- libasound2
- libasound2-plugins
- alsa-utils
after:
- alsa-config
# prime:
# - etc/asound.conf
override-prime: |
snapcraftctl prime
rm -vf usr/lib/jvm/java-*-openjdk-*64/lib/security/blacklisted.certs
Hello, no i did not observe any denials
I have a new update: I tried on my local the following snapcraft.yml
name: fromgtog
version: '7.0.1'
summary: Clone ALL GitHub/Gitea/Local to GitHub/Gitea.
description: |
Helps to clone all repositories from GitHub on Gitea/Local and vice versa.
grade: stable
confinement: strict
base: core24
icon: snap/gui/icon.png
title: FromGtoG
website: https://andre-i.eu
issues: https://github.com/goto-eof
license: MIT
compression: xz
slots:
fromgtog-dbus:
interface: dbus
bus: session
name: it.es5.fromgtog.dbus
apps:
fromgtog:
environment:
ALSA_CONFIG_PATH: $SNAP/etc/asound.conf
LD_LIBRARY_PATH: $LD_LIBRARY_PATH:$SNAP_DESKTOP_RUNTIME/usr/lib/$CRAFT_ARCH_TRIPLET_BUILD_FOR/libproxy:$SNAP_DESKTOP_RUNTIME/usr/lib/$CRAFT_ARCH_TRIPLET_BUILD_FOR/gio/modules
command: executor
extensions: [ gnome ]
plugs:
- network
- x11
- browser-support
- unity7
- home
- desktop
- desktop-legacy
- removable-media
- wayland
- network-bind
- pulseaudio
- alsa
slots:
- fromgtog-dbus
parts:
wrapper:
plugin: dump
source: snap/local
source-type: local
alsa-config:
plugin: dump
source: snap/local/asound.conf
source-type: file
organize:
asound.conf: etc/asound.conf
prime:
- etc/asound.conf
application:
plugin: maven
source: .
build-packages:
- openjdk-21-jdk
- maven
stage-packages:
- openjdk-21-jre
- glib-networking
- libgtk-3-0
- xdg-utils
- libasound2
- libasound2-plugins
- alsa-utils
after:
- alsa-config
override-prime: |
snapcraftctl prime
rm -vf usr/lib/jvm/java-*-openjdk-*64/lib/security/blacklisted.certs
After enabling manually the connections it worked:
sudo snap connect fromgtog:pulseaudio
sudo snap connect fromgtog:alsa
snap connections fromgtog
Interface Plug Slot Notes
alsa fromgtog:alsa - -
browser-support fromgtog:browser-support :browser-support -
content[gnome-46-2404] fromgtog:gnome-46-2404 gnome-46-2404:gnome-46-2404 -
content[gpu-2404] fromgtog:gpu-2404 mesa-2404:gpu-2404 -
content[gtk-3-themes] fromgtog:gtk-3-themes gtk-common-themes:gtk-3-themes -
content[icon-themes] fromgtog:icon-themes gtk-common-themes:icon-themes -
content[sound-themes] fromgtog:sound-themes gtk-common-themes:sound-themes -
dbus - fromgtog:fromgtog-dbus -
desktop fromgtog:desktop :desktop -
desktop-legacy fromgtog:desktop-legacy :desktop-legacy -
gsettings fromgtog:gsettings :gsettings -
home fromgtog:home :home -
network fromgtog:network :network -
network-bind fromgtog:network-bind :network-bind -
opengl fromgtog:opengl :opengl -
pulseaudio fromgtog:pulseaudio - -
removable-media fromgtog:removable-media - -
unity7 fromgtog:unity7 :unity7 -
wayland fromgtog:wayland :wayland -
x11 fromgtog:x11 :x11 -
I discovered that the interface pulseaudio was deprecated: The pulseaudio interface
So i replaced it with sound-playback and now my application is able to play sounds!
Thank you again James! You have led me on the right path.
For completeness I am sharing the working yaml file:
name: fromgtog
version: '7.0.1'
summary: Clone ALL GitHub/Gitea/Local to GitHub/Gitea.
description: |
Helps to clone all repositories from GitHub on Gitea/Local and vice versa.
grade: stable
confinement: strict
base: core24
icon: snap/gui/icon.png
title: FromGtoG
website: https://andre-i.eu
issues: https://github.com/goto-eof
license: MIT
compression: xz
slots:
fromgtog-dbus:
interface: dbus
bus: session
name: it.es5.fromgtog.dbus
apps:
fromgtog:
environment:
ALSA_CONFIG_PATH: $SNAP/etc/asound.conf
LD_LIBRARY_PATH: $LD_LIBRARY_PATH:$SNAP_DESKTOP_RUNTIME/usr/lib/$CRAFT_ARCH_TRIPLET_BUILD_FOR/libproxy:$SNAP_DESKTOP_RUNTIME/usr/lib/$CRAFT_ARCH_TRIPLET_BUILD_FOR/gio/modules
command: executor
extensions: [ gnome ]
plugs:
- network
- x11
- browser-support
- unity7
- home
- desktop
- desktop-legacy
- removable-media
- wayland
- network-bind
- audio-playback
- alsa
slots:
- fromgtog-dbus
platforms:
amd64:
build-on: [ amd64 ]
build-for: [ amd64 ]
arm64:
build-on: [ arm64 ]
build-for: [ arm64 ]
parts:
wrapper:
plugin: dump
source: snap/local
source-type: local
alsa-config:
plugin: dump
source: snap/local/asound.conf
source-type: file
organize:
asound.conf: etc/asound.conf
prime:
- etc/asound.conf
application:
plugin: maven
source: .
build-packages:
- openjdk-21-jdk
- maven
stage-packages:
- openjdk-21-jre
- glib-networking
- libgtk-3-0
- xdg-utils
- libasound2
- libasound2-plugins
- alsa-utils
after:
- alsa-config
override-prime: |
snapcraftctl prime
rm -vf usr/lib/jvm/java-*-openjdk-*64/lib/security/blacklisted.certs
While in Java I do something like that to load the clip:
private Clip loadClip(String soundFilename) {
try {
InputStream soundStream = SoundPlayer.class.getResourceAsStream(soundFilename);
URL soundURL = getClass().getClassLoader().getResource(soundFilename);
if (soundURL == null) {
logger.error("File not found: {}", soundFilename);
return null;
}
logger.info("Loading file: {}", soundFilename);
AudioInputStream audioStream = AudioSystem.getAudioInputStream(soundURL);
Clip clip = AudioSystem.getClip();
clip.open(audioStream);
audioStream.close();
return clip;
} catch (RuntimeException | UnsupportedAudioFileException | IOException |
LineUnavailableException e) {
logger.error("SoundPlayer failed to load clip", e);
}
return null;
}
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