### Question:
JpqlFunctionUtil { public static String unquoteDoubleQuotes(String s) { return unquote(s, '\"'); } private  JpqlFunctionUtil(); static String unquoteSingleQuotes(String s); static String unquoteDoubleQuotes(String s);  }### Answer:
@Test public void testUnquoteDoubleQuotes() { assertEquals("0", JpqlFunctionUtil.unquoteDoubleQuotes("0")); assertEquals("0", JpqlFunctionUtil.unquoteDoubleQuotes("\"0\"")); assertEquals("\"0\"", JpqlFunctionUtil.unquoteDoubleQuotes("\"\"0\"\"")); }