Questions tagged [writable]
121 questions
0
votes
0 answers
Empty value in write() method : Custom Datatype in Hadoop MapReduce
I am emitting two 2D double arrays as key and value. I am constructing WritableComparable class.
public class MF implements WritableComparable{
/**
* @param args
*/
private double[][] value;
public MF() {
// TODO Auto-generated…
user2922060
0
votes
1 answer
Writable Issue: Not able to print the contents
My input value to reducer is a double array.
719.000 501.000 -75.000
501.000 508.000 -62.000
-75.000 -62.000 10.000
In my reducer i need to print this matrix.so i did
public void reduce(IntWritable key,
Iterable…
user2922060
0
votes
1 answer
Save and read complicated Writable value in Hadoop job
I need to move complicated value (implements Writable) from output of 1st map-reduce job to input of other map-reduce job. Results of 1st job saved to file. File can store Text data or BytesWritable (with default output \ input formats). So I need…
user2737635
0
votes
2 answers
Hashmap in Hadoop
I would like to use the hashmap class defined in java.util.* in hadoop program.
A hashmap in Java is instantiated using Map D = new HashMap();
When you use the above line and compile with hadoop jar , it throws an error as Map is used for something…
user2623946
- 55
- 1
- 13
0
votes
1 answer
Serialization in Hadoop - Writable
This is the class that implements Writable ..
public class Test implements Writable {
List atoms = new ArrayList();
public void write(DataOutput out) throws IOException {
IntWritable size = new…
rekha gupta
- 27
- 4
0
votes
1 answer
Updating dependencies of writable computed observable
I'm trying use knockout.js' computed observables to setup C#-like properties on a model. I want observable to only accept valid values. Simplified example:
function Model()
{
var a = 100;
var b = 200;
var $ = this;
this.a =…
zzandy
- 2,263
- 1
- 23
- 43
0
votes
1 answer
Parent Directory is not Writable Error Android Emulator
Getting "Parent directory of file is not writable" when trying to create a temp file. I am using Eclipse and the emulator. I am using the permission in my Manifest:
Kristy Welsh
- 7,828
- 12
- 64
- 106
0
votes
2 answers
Writing to different tables from writable view
I want to write to different tables depending on the state of my development (b=backup, t=testing).
The minimal example showing the problem is the following:
SELECT s.Monat FROM (
SELECT 'b' as mode, * FROM [BACKUP].IstMonat
UNION
SELECT 't' as…
Felix Moeller
- 35
- 4
0
votes
0 answers
hdfs text with 3rd party writable
I have generated an hdfs sequence file and it uses a 3rd party library's Writable, so when I try to show the text of the file by running hadoop fs -text /some/file/path, I get an error message saying:
text: java.io.IOException: WriableName can't…
Jeff Storey
- 56,312
- 72
- 233
- 406
0
votes
1 answer
Hadoop Serialization Nested Objects
I have a class:
class Class1 implements Writable{
int intField;
double doubleField;
Class2 refToClass2;
public void readField(DataInput in){...}
public void write(DataOutput out){...}
class Class2 implements…
Razvan
- 9,925
- 6
- 38
- 51
0
votes
3 answers
Multiple Custom Writable formats
I have multiple input sources and I have used Sqoop's codegen tool to generate custom classes for each input source
public class SQOOP_REC1 extends SqoopRecord implements DBWritable, Writable
public class SQOOP_REC2 extends SqoopRecord …
haden
- 164
- 1
- 6
-1
votes
1 answer
Kubernetes - mount read only share as writable
I am using this config to mount drive that is read-only to docker image:
volumes:
- name: drive-c
hostPath:
path: /media/sf_C_DRIVE
containers:
...
volumeMounts:
- name: drive-c
mountPath: /c
When I try to write (mkdir)…
Bojan Vukasovic
- 2,054
- 22
- 43
-1
votes
1 answer
Using toString when setting object prototype to null
If I set the prototype to null, then how come I can still use toString on the object?
var nakedObject=Object.create(null,{
name:{
configurable:true,
enumerable:true,
value:"Hello",
writable:true
}
});
…
akotch
- 215
- 5
- 11
-1
votes
1 answer
Why to use Writable when we can directly use DataInput and DataOutput?
Probably because implementing Writable would present us with a serializable object. I know DataInput and DataOutput directly deal with byte streams but I see no harm in directly reading values off them and storing it in primitive types too.
That…
Aakash Verma
- 3,705
- 5
- 29
- 66
-1
votes
2 answers
How to pass string as value in mapper?
I am trying to pass a string as value in the mapper, but getting error that it is not Writable. How to resolve?
public void map(LongWritable key, Text value, Context context) throws IOException, InterruptedException {
String TempString =…
Raunak Tibrewal
- 1
- 3