### Question:
NetShellConfiguration extends PersistentObject { public void save(File file) throws IOException { super.saveToFile(file.getPath()); this.canSet = false; this.global.readOnly(); } NetShellConfiguration(boolean canSet);  NetShellConfiguration(); static NetShellConfiguration getInstance(); GlobalConfiguration getGlobal(); final synchronized void setGlobal(GlobalConfiguration global); void save(File file); @JsonIgnore
    static String DEFAULT_FILENAME; }### Answer:
@Test public void testSave() throws Exception { }