Java小數點格式化

1.BigDecimal

import java.math.BigDecimal;

import java.math.RoundingMode;

BigDecimal bd = new BigDecimal(輸入);

bd = bd.setScale(小數位數, RoundingMode.HALF_UP);

2.DecimalFormat

import java.math.RoundingMode;

import java.text.DecimalFormat;

DecimalFormat df = new DecimalFormat("0.00");

df.setRoundingMode(RoundingMode.HALF_UP);

df.format(輸入);

MySQL參數

wait_timeout
等待非交互式連接的秒數

interactive_timeout
等待交互式連接的秒數
交互式客戶端定義為在mysql_real_connect（）中使用CLIENT_INTERACTIVE選項的客戶端

Java發送Request

URL urlObtainToken = new URL(URL);
HttpURLConnection connectionObtainToken = (HttpURLConnection) urlObtainToken.openConnection();
connectionObtainToken.setRequestMethod("POST");

connectionObtainToken.setDoOutput(true);
OutputStreamWriter writer = new OutputStreamWriter(connectionObtainToken.getOutputStream());
writer.write("...");
writer.close();
if (connectionObtainToken.getResponseCode() == HttpURLConnection.HTTP_OK) {}