Hadoop C ++ HDFS测试运行异常 [英] Hadoop C++ HDFS test running Exception
问题描述
我正在使用Hadoop 2.2.0并尝试运行此 hdfs_test.cpp 应用程序:
I'm working with Hadoop 2.2.0 and trying to run this hdfs_test.cpp application:
#include "hdfs.h"
int main(int argc, char **argv) {
hdfsFS fs = hdfsConnect("default", 0);
const char* writePath = "/tmp/testfile.txt";
hdfsFile writeFile = hdfsOpenFile(fs, writePath, O_WRONLY|O_CREAT, 0, 0, 0);
if(!writeFile) {
fprintf(stderr, "Failed to open %s for writing!\n", writePath);
exit(-1);
}
char* buffer = "Hello, World!";
tSize num_written_bytes = hdfsWrite(fs, writeFile, (void*)buffer, strlen(buffer)+1);
if (hdfsFlush(fs, writeFile)) {
fprintf(stderr, "Failed to 'flush' %s\n", writePath);
exit(-1);
}
hdfsCloseFile(fs, writeFile);
}
我编译它,但是当我用 ./ hdfs_test 我有这个:
I compiled it but when I'm running it with ./hdfs_test I have this:
loadFileSystems error:
(unable to get stack trace for java.lang.NoClassDefFoundError exception: ExceptionUtils::getStackTrace error.)
hdfsBuilderConnect(forceNewInstance=0, nn=default, port=0, kerbTicketCachePath=(NULL), userName=(NULL)) error:
(unable to get stack trace for java.lang.NoClassDefFoundError exception: ExceptionUtils::getStackTrace error.)
hdfsOpenFile(/tmp/testfile.txt): constructNewObjectOfPath error:
(unable to get stack trace for java.lang.NoClassDefFoundError exception: ExceptionUtils::getStackTrace error.)
Failed to open /tmp/testfile.txt for writing!
也许是类路径的问题。
我的$ HADOOP_HOME是/ usr / local / hadoop,这是我的实际变量* CLASSPATH * :
Maybe is a problem with the classpath. My $HADOOP_HOME is /usr/local/hadoop and this is my actually variable *CLASSPATH*:
echo $CLASSPATH
/usr/local/hadoop/etc/hadoop:/usr/local/hadoop/share/hadoop/common/lib/*:/usr/local/hadoop/share/hadoop/common/*:/usr/local/hadoop/share/hadoop/hdfs:/usr/local/hadoop/share/hadoop/hdfs/lib/*:/usr/local/hadoop/share/hadoop/hdfs/*:/usr/local/hadoop/share/hadoop/yarn/lib/*:/usr/local/hadoop/share/hadoop/yarn/*:/usr/local/hadoop/share/hadoop/mapreduce/lib/*:/usr/local/hadoop/share/hadoop/mapreduce/*:/contrib/capacity-scheduler/*.jar
任何帮助。感谢。
推荐答案
在类路径中使用基于JNI的程序。尝试使用 direct-jar-in-classpath 方法,例如在 https://github.com/QwertyManiac/cdh4-libhdfs-example/blob/master/exec.sh#L3 ,我相信它应该工作。 https://github.com/QwertyManiac/cdh4-libhdfs-example目前正在工作。
I've faced problems with using wildcards in classpath when using JNI based programs. Try the direct-jar-in-classpath approach, such as the one generated in this sample code of mine at https://github.com/QwertyManiac/cdh4-libhdfs-example/blob/master/exec.sh#L3, and I believe it should instead work. The whole contained example at https://github.com/QwertyManiac/cdh4-libhdfs-example does work presently.
另请参阅 http://stackoverflow.com/ a / 9322747/1660002
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