java.lang.UnsupportedOperationException

2015-06-23 14:50:12   作者：MangoCool   来源：MangoCool

在Scala的学习中，List集合并非像Java集合那样是可变的。如果要使用到可变的集合，就须要用ListBuffer；否则一旦使用了List，如果在后续设计到要操作集合，将会抛出异常：java.lang.UnsupportedOperationException

def main(agrs: Array[String]) {
    try {
      val sf = ("zhangsan","90","270")
      val lists = List[(String, String, String)]()
      lists.add(sf)
    } catch {
      case e: Exception => {
        e.printStackTrace
    }
  }
}

运行就会抛出异常：

java.lang.UnsupportedOperationException
at java.util.AbstractList.add(AbstractList.java:148)
at java.util.AbstractList.add(AbstractList.java:108)
at HbaseTest$.main(HbaseTest.scala:112)
at HbaseTest.main(HbaseTest.scala)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at com.intellij.rt.execution.application.AppMain.main(AppMain.java:134)

更改List为ListBuffer即可！

标签： Scala Java List exception

分享：

上一篇org.apache.spark.SparkException: Job aborted due to stage failure: Task 0.0 in stage 2.0 (TID 2) had a not serializable result: org.apache.hadoop.hbase.io.ImmutableBytesWritable

下一篇Scala的基础学习（三）数据类型