/usr/share/doc/libhamcrest1.2-java/api/package-list is in libhamcrest1.2-java-doc 1.2-0ubuntu1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 | org.hamcrest
org.hamcrest.beans
org.hamcrest.collection
org.hamcrest.core
org.hamcrest.integration
org.hamcrest.internal
org.hamcrest.number
org.hamcrest.object
org.hamcrest.text
org.hamcrest.xml
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