Hi,
Thanks for the kind reply.
If only the common and mapred are used, then what is hadoop-hdfs-0.21.0.jar
used for?
My code looks like this:
*import java.util.*;*
*import java.lang.*;*
*import java.io.*;*
*import org.apache.hadoop.*;*
*
*
*class MapReduce {*
* *
* public static void main(String[] args) throws Exception {*
* *
* try {*
* Path pt=new Path(
"hdfs://localhost:54310//Users/arko/Documents/Research/HDFS/abc");*
* FileSystem fs = FileSystem.get(new Configuration());*
* BufferedWriter br=new
BufferedWriter(newOutputStreamWriter(fs.create(pt,
true)));*
* String line;*
* line="Testing";*
* System.out.println(line);*
* br.write(line);*
* br.close();*
* }catch(Exception e){*
* System.out.println("File not found");*
* }*
* }*
*}*
When I compile the code, I get the following erros:
*$javac -classpath
/Users/arko/Documents/hadoop-0.21.0/hadoop-common-0.21.0.jar -d class/
FileSystemCat.java clear*
FileTest.java:16: cannot find symbol
symbol : class Path
location: class FileTest
Path pt=new
Path("hdfs://localhost:54310//Users/arko/Documents/Research/HDFS/abc");
^
FileTest.java:16: cannot find symbol
symbol : class Path
location: class FileTest
Path pt=new
Path("hdfs://localhost:54310//Users/arko/Documents/Research/HDFS/abc");
^
FileTest.java:17: java.io.FileSystem is not public in java.io; cannot be
accessed from outside package
FileSystem fs = FileSystem.get(new Configuration());
^
FileTest.java:17: cannot find symbol
symbol : class Configuration
location: class FileTest
FileSystem fs = FileSystem.get(new Configuration());
^
FileTest.java:17: java.io.FileSystem is not public in java.io; cannot be
accessed from outside package
FileSystem fs = FileSystem.get(new Configuration());
^
5 errors
Thanks again for help!
Warm Regards
Arko
On Wed, Aug 31, 2011 at 5:00 PM, Robert Evans <[email protected]> wrote:
> You should be able to use hadoop-common-0.21.0.jar for accessing HDFS
> APIS and use hadoop-mapred.0.21.0.jar for accessing the mapreduce APIs. I
> cannot really comment further on compilation errors without seeing the
> code/error messages.
>
> --Bobby Evans
>
>
> On 8/31/11 4:34 PM, "Arko Provo Mukherjee" <[email protected]>
> wrote:
>
> Hello,
>
> I am trying to learn Hadoop and doing a project on it.
>
> I need to update some files in my project and hence wanted to use version
> 0.21.0
>
> However, I am confused as to how I can compile my programs on version
> 0.21.0 as it doesn't have any hadoop-core-0.21.0.jar file. What option
> should I have to give in the -classpath option?
> I can see three different JAR files namely hadoop-common-0.21.0.jar,
> hadoop-hdfs-0.21.0.jar & hadoop-mapred-0.21.0.jar.
>
> I am getting compilation errors which using the the common jar file.
>
> Also I would like to learn the FileContext Library as the docs that I have
> read says that it has a simpler interface than the FileSystem. However, I
> cannot find any links to some example code which can help me to grasp the
> API. Request you to kindly share any link / code snippet to demonstrate the
> use of the new API.
>
> Many thanks in advance for your kind response.
>
> Warm regards
> Arko
>
>
