If you want to see a live example of the capabilities of the Java Ecosystem, you can have a look at SonarQube on SonarQube.
Analysing a Java project without providing the Java bytecode of the source files and of all the project dependencies (jar files) is possible but will lead to highly decrease the number of issues found by the analyzer (false-negatives). Moreover the detection of cycles between packages and the display of the DSM will be automatically deactivated. As soon as a class required to efficiently do an analysis is missing a warning like the following one is logged :
[WARN] [08:40:21.769] Class 'XXXXXX' is not accessible through the ClassLoader.
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