Fingerprinting code

gistfile1.java

            FingerprintMap map = Hudson.getInstance().getFingerprintMap();
            Map<String,String> fingerprints = new HashMap<String, String>();
            
            FilePath[] list = srcDir.list(expandedFilter);
            for (FilePath file : list) {
                String digest = file.digest(); 
                map.getOrCreate(null, file.getName(), digest).add(build);
                fingerprints.put(file.getName(), digest);
            }   
            
            // add action
            FingerprintAction fa = build.getAction(FingerprintAction.class);
            if (fa != null) fa.add(fingerprints);
            else            build.getActions().add(new FingerprintAction(build, fingerprints));