我在ec2示例中安装了sqoop，引用http://kontext.tech/docs/dataandbusinessintelligence/p/configure-sqoop-in-a-edge-node-of-hadoop-cluster 我的hadoop集群也运行良好。
我搞错了 Error: Could not find or load main class org.apache.hadoop.mapreduce.v2.app.MRAppMaster 我用上面提到的方法解决了这个问题。但不幸的是，我在运行sqoop import时遇到另一个错误： Container exited with a non-zero exit code 1. Error file: prelaunch.err. Last 4096 bytes of prelaunch.err : Last 4096 bytes of stderr : Error: Could not find or load main class org.apache.hadoop.mapred.YarnChild .
请建议我如何克服这个错误。
以下是我的sqoop-env.template.sh的外观：

# Licensed to the Apache Software Foundation (ASF) under one or more

# contributor license agreements.  See the NOTICE file distributed with

# this work for additional information regarding copyright ownership.

# The ASF licenses this file to You under the Apache License, Version 2.0

# (the "License"); you may not use this file except in compliance with

# the License.  You may obtain a copy of the License at

# http://www.apache.org/licenses/LICENSE-2.0

# Unless required by applicable law or agreed to in writing, software

# distributed under the License is distributed on an "AS IS" BASIS,

# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

# See the License for the specific language governing permissions and

# limitations under the License.

# included in all the hadoop scripts with source command

# should not be executable directly

# also should not be passed any arguments, since we need original $*

# Set Hadoop-specific environment variables here.

# Set path to where bin/hadoop is available

# export HADOOP_COMMON_HOME=$HOME/hadoop-3.1.0

# Set path to where hadoop-*-core.jar is available

# export HADOOP_MAPRED_HOME=$HOME/hadoop-3.1.0

# set the path to where bin/hbase is available

# export HBASE_HOME=

# Set the path to where bin/hive is available

# export HIVE_HOME=

# Set the path for where zookeper config dir is

# export ZOOCFGDIR=`