请有人帮帮我，我正在尝试在haoopYarn上安装spark，我遇到以下错误：

org.apache.spark.SparkException: Yarn application has already ended! It might have been killed or unable to launch application master.
        at org.apache.spark.scheduler.cluster.YarnClientSchedulerBackend.waitForApplication(YarnClientSchedulerBackend.scala:113)
        at org.apache.spark.scheduler.cluster.YarnClientSchedulerBackend.start(YarnClientSchedulerBackend.scala:59)
        at org.apache.spark.scheduler.TaskSchedulerImpl.start(TaskSchedulerImpl.scala:141)
        at org.apache.spark.SparkContext.<init>(SparkContext.scala:379)
java.lang.NullPointerException
    at org.apache.spark.sql.SQLContext.<init>(SQLContext.scala:141)
    at org.apache.spark.sql.hive.HiveContext.<init>(HiveContext.scala:49)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:526)

hadoop守护进程包括：

4064 SecondaryNameNode
3478 NameNode
4224 ResourceManager
4480 NodeManager
3727 DataNode
6279 Jps

和bash文件：

export JAVA_HOME=/home/user/hadoop-two/jdk1.7.0_71
export HADOOP_INSTALL=/home/user/hadoop-two/hadoop-2.6.0
export PATH=$PATH:$HADOOP_INSTALL/bin
export PATH=$PATH:$HADOOP_INSTALL/sbin
export HADOOP_MAPRED_HOME=$HADOOP_INSTALL
export HADOOP_COMMON_HOME=$HADOOP_INSTALL
export HADOOP_HDFS_HOME=$HADOOP_INSTALL
export YARN_HOME=$HADOOP_INSTALL
export HADOOP_COMMON_LIB_NATIVE_DIR=$HADOOP_INSTALL/lib/native
export HADOOP_OPTS="-Djava.library.path=$HADOOP_INSTALL/lib"
export HADOOP_CONF_DIR=$HADOOP_INSTALL/etc/hadoop
export YARN_CONF_DIR=$HADOOP_INSTALL/etc/hadoop
export SPARK_HOME=/home/user/hadoop-two/spark-1.4.0