java连接mysql并向其中插入数据中文乱码问题

dbhelper boringdb = new dbhelper();
boringdb.connSQL();
String insert = "insert into boring(prflurl,name,post,school,reside) values('www.地址地址f','csdn','好无聊啊','家里蹲大学','北京')";
if (boringdb.insertSQL(insert) == true) {
System.out.println("insert successfully");
}