我正在创建orc文件并向该文件添加行。它在linux上运行。但它在windows.writer.close（）上不起作用，返回NPE。请找到下面的代码和下面的堆栈跟踪，并在这方面给我帮助。代码：--包com.testing；
import java.io.IOException;
import java.util.Arrays;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.hive.ql.io.orc.OrcFile;
import org.apache.hadoop.hive.ql.io.orc.OrcFile.WriterOptions;
import org.apache.hadoop.hive.serde2.objectinspector.ObjectInspector;
import org.apache.hadoop.hive.serde2.typeinfo.TypeInfo;
import org.apache.hadoop.hive.serde2.typeinfo.TypeInfoUtils;
import org.apache.hadoop.hive.ql.io.orc.OrcFile;
import org.apache.hadoop.hive.ql.io.orc.OrcFile.WriterOptions;
import org.apache.hadoop.hive.ql.io.orc.Writer;
public class Typical {
public static void main(String args[]){
String filePath ="C:/usr/tmp/EDMS_FILE_ARCHIVE_.orc";
TypeInfo typeInfo=TypeInfoUtils.getTypeInfoFromTypeString("struct<a:string>");
ObjectInspector inspector=TypeInfoUtils.getStandardJavaObjectInspectorFromTypeInfo(typeInfo);
WriterOptions options=OrcFile.writerOptions(new Configuration()).inspector(inspector);
//Path path=new Path(temporaryFolder.getRoot().getCanonicalPath(),"part-00000");
Writer writer;
try {
writer = OrcFile.createWriter(new Path(filePath),options);
writer.addRow(Arrays.asList("hello"));
writer.close();
} catch (IllegalArgumentException | IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
statcktrace:--
Exception in thread "main" java.lang.NullPointerException
at java.lang.ProcessBuilder.start(Unknown Source)
at org.apache.hadoop.util.Shell.runCommand(Shell.java:482)
at org.apache.hadoop.util.Shell.run(Shell.java:455)
at org.apache.hadoop.util.Shell$ShellCommandExecutor.execute(Shell.java:715)
at org.apache.hadoop.util.Shell.execCommand(Shell.java:808)
at org.apache.hadoop.util.Shell.execCommand(Shell.java:791)
at org.apache.hadoop.fs.RawLocalFileSystem.setPermission(RawLocalFileSystem.java:656)
at org.apache.hadoop.fs.FilterFileSystem.setPermission(FilterFileSystem.java:490)
at org.apache.hadoop.fs.ChecksumFileSystem.create(ChecksumFileSystem.java:462)
at org.apache.hadoop.fs.ChecksumFileSystem.create(ChecksumFileSystem.java:428)
at org.apache.hadoop.fs.FileSystem.create(FileSystem.java:908)
at org.apache.hadoop.fs.FileSystem.create(FileSystem.java:889)
at org.apache.hadoop.hive.ql.io.orc.WriterImpl.getStream(WriterImpl.java:1967)
at org.apache.hadoop.hive.ql.io.orc.WriterImpl.flushStripe(WriterImpl.java:1984)
at org.apache.hadoop.hive.ql.io.orc.WriterImpl.close(WriterImpl.java:2289)
at com.testing.Typical.main(Typical.java:30)
Advance Thanks
Hanuman
在windows上使用orc库并写入本地文件时出现问题：
java.lang.NullPointerException
at java.lang.ProcessBuilder.start(Unknown Source)
程序想要执行chmod命令，但它不存在于windows中——在这里您可以获得NPE。我找到了我不喜欢的变通方法：
- dowload winutils.exe
- System.setProperty（"hadoop.home.dir"，"c:\path\to\winutils"）；wintutils库的实际路径应该是c:\path\to\winutils\bin