### Question:
BaseFineIoReader implements Reader { @Override public boolean isReadable() { return readFile != null && readFile.exists(); }  @Override boolean isReadable(); @Override final void release();  }### Answer:
@Test public void isReadable() throws Exception { assertFalse(fineIoReader.isReadable()); fineIoReader.readFile = readFile; when(readFile.exists()).thenReturn(true, false); assertTrue(fineIoReader.isReadable()); assertFalse(fineIoReader.isReadable()); }