code: public BigInteger getBigInteger(String key) throws JSONException {
  		Object object = this.get(key);
  		try {
  			return new BigInteger(object.toString());
  		} catch (Exception e) {
  			throw new JSONException("JSONObject[" + quote(key)
  					+ "] could not be converted to BigInteger.");
  		}
  	}
docs: Get the BigInteger value associated with a key.
  
  @param key A key string.
  @return The numeric value.
  @throws JSONException if the key is not found or if the value cannot be
  converted to BigInteger.