以太坊：获取ETH余额

    /**
	 * 取余额
	 * 
	 * @param web3j Web3j对象
	 *            
	 * @param address 传入查询的地址
	 *            
	 * @return String 余额
	 * @throws IOException
	 */
	public static String getBalance(Web3j web3j, String address) throws IOException {

		EthGetBalance ethGetBlance = web3j.ethGetBalance(address, DefaultBlockParameterName.LATEST).send();
		// 格式转换 WEI(币种单位) --> ETHER
		String balance = Convert.fromWei(new BigDecimal(ethGetBlance.getBalance()), Convert.Unit.ETHER).toPlainString();

		return balance;
	}