### Question:
ManifestUpdaterImpl implements ManifestUpdater { protected String getImportString() { Set<String> imports = new HashSet<String>(); for ( Map.Entry<String, String> entry : getImports().entrySet() ) { String importString = entry.getKey(); String version = entry.getValue(); if ( version != null ) { importString += ";version=\"" + entry.getValue() + "\""; } imports.add( importString ); } List<String> importList = new ArrayList<String>( imports ); Collections.sort( importList ); return join( importList, "," ); } ManifestUpdaterImpl(); @Override void setBundleSymbolicName( String name ); @Override String getBundleSymbolicName(); @Override Map<String, String> getImports(); @Override Set<String> getExportServices(); @Override void addEntry( Object key, Object value ); @Override void write( java.util.jar.Manifest originalManifest, OutputStream outputStream, String name,
                               String symbolicName, String version );  }### Answer:
@Test public void testGetImportString() { ManifestUpdaterImpl manifestUpdater = new ManifestUpdaterImpl(); manifestUpdater.getImports().put( "test1", null ); manifestUpdater.getImports().put( "test2", "abc" ); assertEquals( "test1,test2;version=\"abc\"", manifestUpdater.getImportString() ); }