描述: 这几天在windows环境上,部署了vagrant,在启动虚拟机的时候报错: [c:\~]$ vagrant upBringing machine 'default' up with 'virtualbox' provider...==> default: Importing base box 'centos'...==> default: Matching MAC address for NAT networking...==> default: Setting the nam…
MySQL报错:The MySQL server is running with the --skip-grant-tables option so it cannot execute this statement等问题 1.登录的mysql:mysql –u root –p mysql> set global read_only=0;(关掉新主库的只读属性) flush privileges; 2.修改mysql配置文件my.cnf,该文件在/etc目录下 重启mysql服务:service…
刚接触Scala时就很奇怪, 为什么Java已经有null了,却偏偏还要弄出个None 后来依然我行我素在Scala里使用null, 结果就是经常被NullPointerException折磨得阴魂不散...于是终于领悟. WHY? 举个例子: 假设有一个简单的对象A, A类里有2个Int属性, a和b case class A(val a : Int, val b : Int) 然后有这么一个map val map1 = Map(1 -> A(111, 1111), 2 -> A(222,…
报错背景: CDH集成kafka插件之后,启动kafka时就报出此错误. 报错现象: -- ::, ERROR state.change.logger: [Controller epoch=] Initiated state change from OfflinePartition to OnlinePartition failed kafka.common.NoReplicaOnlineException: No replica in ISR for partition __consumer_…
报错背景: CDH中集成kafka的服务,解决完kafka的jar包报错之后重启,发现这个报错. 报错现象: java.lang.VerifyError: Instruction type does not match stack map Exception Details: Location: org/eclipse/jetty/servlet/ServletHandler.doStart()V @: putfield Reason: Type ]) is not assignable to…
报错背景: CDH启动kafka的时候出现报错情况,并且报错的节点挂掉. 报错现象: Exiting Kafka due to fatal exception java.lang.AbstractMethodError: nl.techop.kafka.KafkaHttpMetricsReporter.logger()Lcom/typesafe/scalalogging/Logger; at kafka.utils.Logging$class.) at ) at ) at kafka.metri…
===================== Scala语言的高级特性 ========================一.Scala的集合 1.可变集合mutable 不可变集合immutable //不可变集合 val math = scala.collection.immutable.Map("Alice"->80,"Bob"->90) //可变集合 val chinese = scala.collection.mutable.Map("A…
项目当中用到cookie保存中文,但是会报如下错误: Control character in cookie value, consider BASE64 encoding your value 大概意思是保存到cookie当中的值存在控制字符,无法保存.但实际上数据是不存在这种问题的.再看后面的那句话,好像是将要保存的值进行了base64编码,可能是因为中文在编码时出现乱码导致一些控制字符的出现.看来setCookie方法不支持保存中文(GBK)编码的样子. 解决方案:将要保存的值进行URLE…
报错现象: Exception in thread "main" java.lang.NoClassDefFoundError: Lorg/apache/hadoop/fs/FileSystem; at java.lang.Class.getDeclaredFields0(Native Method) at java.lang.Class.privateGetDeclaredFields(Class.java:2583) at java.lang.Class.getDeclaredFi…
1.创建多行字符串,只要把多行字符串放在3个双引号间("""...""")即可.这是Scala对于here document,或者叫heredoc的支持.这里我们创建一个三行长的字符串: MultiLine.scala val str = """Hello world! How are you! Good morning!""" println(str) 输出如下: Hello worl…
