1. Too many connections
數據庫達到最大連接數
mysql> SELECT @@MAX_CONNECTIONS AS 'Max Connections';
mysql> set GLOBAL max_connections=2000;
數據庫達到最大連接數
mysql> SELECT @@MAX_CONNECTIONS AS 'Max Connections';
mysql> set GLOBAL max_connections=2000;
引入依賴 <dependency> <groupId>com.itextpdf</groupId> <artifactId>itextpdf</artifactId>