/usr/share/doc/libjcsp-java/jcsp-demos/raytrace/ is in libjcsp-java-doc 1.1-rc4-1.
This file is owned by root:root, with mode 0o755.
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/usr/share/doc/libjcsp-java/jcsp-demos/raytrace/Counter.java
/usr/share/doc/libjcsp-java/jcsp-demos/raytrace/Farmer.java
/usr/share/doc/libjcsp-java/jcsp-demos/raytrace/FrameDeMux.java
/usr/share/doc/libjcsp-java/jcsp-demos/raytrace/Harvester.java
/usr/share/doc/libjcsp-java/jcsp-demos/raytrace/ImageDef.java
/usr/share/doc/libjcsp-java/jcsp-demos/raytrace/ImagePacket.java
/usr/share/doc/libjcsp-java/jcsp-demos/raytrace/Main.java
/usr/share/doc/libjcsp-java/jcsp-demos/raytrace/Picasa.ini
/usr/share/doc/libjcsp-java/jcsp-demos/raytrace/ResultPacket.java
/usr/share/doc/libjcsp-java/jcsp-demos/raytrace/Sky.java
/usr/share/doc/libjcsp-java/jcsp-demos/raytrace/WorkPacket.java
/usr/share/doc/libjcsp-java/jcsp-demos/raytrace/Worker.java
/usr/share/doc/libjcsp-java/jcsp-demos/raytrace/WorkerConst.java
/usr/share/doc/libjcsp-java/jcsp-demos/raytrace/clouds.jpg