### Question:
Attribute implements Map.Entry<String, String>, Cloneable { public String html() { StringBuilder sb = StringUtil.borrowBuilder(); try { html(sb, (new Document("")).outputSettings()); } catch(IOException exception) { throw new SerializationException(exception); } return StringUtil.releaseBuilder(sb); } Attribute(String key, String value);  Attribute(String key, String val, Attributes parent); String getKey(); void setKey(String key); String getValue(); String setValue(String val); String html(); @Override String toString(); static Attribute createFromEncoded(String unencodedKey, String encodedValue); @Override boolean equals(Object o); @Override int hashCode(); @Override Attribute clone();  }### Answer:
@Test public void html() { Attribute attr = new Attribute("key", "value &"); assertEquals("key=\"value &amp;\"", attr.html()); assertEquals(attr.html(), attr.toString()); }