I have a project that reads from mongodb and sends that information to the queue. my listener picks up the queue message from cloud. I am able to create a .txt file that inputs all the information inside from the queue. My problem that I have been searching for is: How can I sort through a specific field inside the POJO (IBusiness1,IBusiness2,IBusiness3)and create the file for each? The following code allows me to create only 1 txt file and it does not sort the field:
public static void main(String[] args) {
SpringApplication.run(PaymentPortalBatchListenerApplication.class, args);
}
private class MessageHandler implements IMessageHandler {
private final Logger logger = LoggerFactory.getLogger(MessageHandler.class);
public CompletableFuture<Void> onMessageAsync(IMessage message) {
System.out.println("received "+message.getBody());
ObjectMapper om = new ObjectMapper();
PortalList auditList = null;
try {
auditList = om.readValue( message.getBody(), PortalList.class );
System.out.println( "**Audit Message " + auditList );
logger.info( "Creating file");
String exportFilePath = "C:\\filewriter\\IBusiness1 " +
LocalDateTime.now().format(formatter) + ".txt";
File file = new File(exportFilePath);
FileWriter writeToFile = new FileWriter(file);
String exportFileHeader = "CREATE_DTTM|FNAME|LNAME|IBusiness";
StringHeaderWriter headerWriter = new
StringHeaderWriter(exportFileHeader);
writeToFile.write(exportFileHeader);
writeToFile.write( String.valueOf( headerWriter));
writeToFile.write( String.valueOf(auditList));
writeToFile.flush();
} catch (IOException e) {
e.printStackTrace();
}
// System.out.println(auditList);
return CompletableFuture.completedFuture(null);
}
Here is what I did:
PaymentPortalBean = POJO
auditlist =on-prem copy of PPB
PortalList =
import lombok.Data;
import java.util.List;
#Data
public class PortalList{
private List<PaymentPortalBean> portalList;
}
answer to creating files:
for(PaymentPortalBean bean: auditList.getPortalList()) {
if(bean.RxBusiness().contains( "IBusiness")){
File file = new File( exportFilePath );
FileWriter writeToFile = new FileWriter( file );
String exportFileHeader = CREATE_DTTM|FNAME|LNAME|IBusiness";
writeToFile.write( exportFileHeader );
writeToFile.write( String.valueOf(bean));
writeToFile.flush();
}
that worked to to find IBusiness, I created two more conditional statements for the types I needed. runs fine.
Mongo db was able to separate the fields I needed.
Related
I am trying to implement an Helper class using OpenCSV and I am thinking to define the related methods as static like this:
public class CsvHelper {
private enum Headers {
ID,
NAME,
EMAIL,
COUNTRY
}
public static List<EmployeeRequest> csvToEmployees(InputStream is) throws IllegalAccessException {
try (BufferedReader reader = new BufferedReader(new InputStreamReader(is, StandardCharsets.UTF_8));
CSVParser parser = new CSVParser(reader,
CSVFormat.DEFAULT.withFirstRecordAsHeader().withIgnoreHeaderCase().withTrim())) {
List<EmployeeRequest> employees = new ArrayList<>();
Iterable<CSVRecord> records = parser.getRecords();
for (CSVRecord rec : records) {
EmployeeRequest employee = new EmployeeRequest(
Long.parseLong(rec.get(Headers.ID)),
rec.get(Headers.NAME),
rec.get(Headers.EMAIL),
rec.get(Headers.COUNTRY)
);
employees.add(employee);
}
return employees;
} catch (IOException e) {
throw new IllegalAccessException("Failed: " + e.getMessage());
}
}
}
However, I am not sure if I should define csvToEmployees method without static in a service class for proper testing. So:
1. Should I define csvToEmployees method in this Helper class as static? Or should I define it in y service as the other service methods (without static)?
2. Can I write Unit and Integration test for reading data from CSV file? Or should I write only Integration test for that?
I need to store and read ArrayList Objects to a file, which that itself isn't the issue. I need to store it with a specific format and have it have a "header" of sorts while still having each ArrayList Object be usable from the file. Another part to it, is it needs to be readable by opening the text file itself, so no serialization can be used (Unless I'm just severely mistaken on how to use serialization). Example of how the working file should look below (Figure 1).
I will include all my code below just so nothing important isn't show on accident.
Airline.java
public class Airline extends Application {
#Override
public void start(Stage stage) throws Exception {
Parent root = FXMLLoader.load(getClass().getResource("Airline.fxml"));
Scene scene = new Scene(root);
stage.setTitle("Seat Reservation");
stage.setResizable(false);
stage.setScene(scene);
stage.show();
}
public static void main(String[] args) {
Passenger p1 = new Passenger(0001, "John Smith", "1A", "AA12");
Passenger p2 = new Passenger(0002, "Annah Smith", "1B", "AA12");
//creating arraylist
ArrayList <Passenger> pList = new ArrayList <Passenger>();
pList.add(p1);
pList.add(p2);
try {
FileOutputStream fos = new FileOutputStream(new
File("reservations.txt"));
ObjectOutputStream oos = new ObjectOutputStream(fos);
oos.writeObject(pList);
oos.close();
fos.close();
FileInputStream fis = new FileInputStream(new
File("reservations.txt"));
ObjectInputStream ois = new ObjectInputStream(fis);
ArrayList list = (ArrayList) ois.readObject();
System.out.println(list.toString());
ois.close();
fis.close();
} catch (FileNotFoundException e) {
System.out.println("File not found");
} catch (IOException e) {
System.out.println("Error initializing stream");
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
launch(args);
}
}
Passenger.java
public class Passenger implements Serializable {
private static final long serialVersionUID = 1L;
private int id;
private String name;
private String seat;
private String flight;
Passenger() {
};
public Passenger (int idP, String nameP,String seatP, String flightP) {
this.id = idP;
this.name = nameP;
this.seat = seatP;
this.flight = flightP;
}
#Override
public String toString() {
return "\n" + id + " " + name + " " + seat + " " + flight;
}
}
The code I have currently shows this when opening the text file (Figure 2 below).
If anyone has any suggestions please let me know! I've been stumped for quite a while now.
Also, if this breaks any rules or doesn't have the proper tags, let me know and I'll remove/edit it.
In your example you use serialization (you can read more about it here Introduction to Java Serialization), which saves an object to a file in binary format. So basically you're saving the whole ArrayList, including its internal fields and values as an array of bytes.
But what you really need is simply writing to a text file.
Here's one of the ways you can do that using java.io.PrintWriter:
PrintWriter p = new PrintWriter("reservations.txt");
p.write("your text goes here");
And yes, you have to prepare the text for writing manually.
In your case the best approach would be overriding toString() method of Passenger class, so you can write to a file as simply as this:
Passenger p1 = new Passenger(0001, "John Smith", "1A", "AA12");
Passenger p2 = new Passenger(0002, "Annah Smith", "1B", "AA12");
p.write(p1.toString());
p.write(p2.toString());
toString() method has to concatenate required fields(ID, Name, SeatNumber, Flight#) and return them as a single String with a TAB character as a delimiter.
I want to create a class that wraps Properties and specifically hides the file I/O operations. I have come up with the abridged code below. This is intended to read the properties from a file at a fixed location outside of the class path. It also has a method to write the properties to the same file.
//
/* Defines key properties of the iFlag application.
* Methods read and write properties.
*/
public class ClientProperties {
private Properties props;
private static String xPanelSizeStg = "32";
private static int xPanelSize = 32;
private static String configFilename = "/home/myname/config/client_config.properties";
public ClientProperties() {
props = new Properties();
}
/**
* Reads properties from file
* Reads the current properties object from file.
* The file is stored in /home/mimibox/config/flag_config.properties
*/
public Properties readPropertiesFromFile( ){
// create and load default properties
InputStream input = null;
logger.trace("Read flag config properties.");
try {
input = new FileInputStream( configFilename );
//load a properties file from class path, inside static method
props.load(input);
//get the property values and save
xPanelSizeStg = props.getProperty("xPanelsize","32");
yPanelSizeStg = props.getProperty("yPanelsize", "32");
}
catch (IOException ex) {
logger.error("Could not open config file" + configFilename,ex );
}
finally{
if(input!=null){
try {
input.close();
}
catch (IOException e) {
logger.error( "Could not close config file" + configFilename,e );
}
}
}
return props;
}
/**
* Writes properties to file
* Writes the current properties object to file.
* The file is stored in /home/mimibox/config/flag_config.properties
*/
public void writePropertiesToFile() {
//saves the current properties to file. Overwrites the existing properties.
Properties props = new Properties(); //a list of properties
OutputStream outStrm = null;
logger.info("Writing default flag config properties.");
System.out.println("Panel size x = " + xPanelSizeStg );
try {
outStrm = new FileOutputStream( configFilename );
// set the properties values
props.setProperty("xPanelsize", xPanelSizeStg);
props.setProperty("yPanelsize", yPanelSizeStg);
// save properties to file, include a header comment
props.store(outStrm, "This is the Server configuration file");
} catch (IOException io) {
logger.error( "The file :{0} could not be opened", configFilename,io);
} finally {
if (outStrm!= null) {
try {
outStrm.close();
} catch (IOException e) {
logger.error("The file :{0} could not be closed", configFilename, e);
}
}
}
}
}
The read and write methods work. What doesn't work is trying to change the value of a property, and then save it. The demo code below successfully reads the properties file and displays the correct value for XPanelsize.
I then change that value and attempt to write the properties to a file. The new value 64 for xPanelsize is not written to the file.
public static void main(String[] args) {
Properties props;
ClientProperties p = new ClientProperties();
props = p.readPropertiesFromFile();
String txt = props.getProperty("xPanelsize");
System.out.println("Panel size x = " + txt );
p.setProperty("xPanelsize","64"); //method not found error
p.writePropertiesToFile();
So I would like to be able to use the Property.setProperty() method to set the value of a property. When I do that, the changed property is not written to the file. I can see that is because I have more than 1 Property instance and one is not visible to the other. I think I need to extend the built-in Properties class to achieve what I want to do, but I am not sure how to make it all work.
I have found plenty of examples of using Properties on the internet. What I haven't found are any examples that hide the related file I/O in a class. How would I do that??
OK so thanks to the comments and answers above, I have made a number of changes. For the benefit of those that stumble upon this post, I have posted the working code in this answer. The main change is to extend Properties. This allows me to use the Properties methods directly.
package com.test;
import java.util.Properties;
import java.io.FileOutputStream;
import java.io.FileInputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.IOException;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import java.io.File;
public class ClientProperties extends Properties {
//initiate logger
private final static Logger logger = LogManager.getLogger();
private static String xPanelSizeStg = "32";
private static String yPanelSizeStg = "32";
private final configFilename = "/home/myname/myConfig.properties";
public ClientProperties() {
}
public Properties readPropertiesFromFile( ){
// create and load default properties
InputStream input = null;
logger.trace("Read flag config properties.");
try {
input = new FileInputStream( configFilename );
//load a properties file from class path, inside static method
this.load(input);
//get the property values and save
xPanelSizeStg = this.getProperty("xPanelsize","32");
yPanelSizeStg = this.getProperty("yPanelsize", "32");
}
catch (IOException ex) {
logger.error("Could not open config file" + configFilename,ex );
}
finally{
if(input!=null){
try {
input.close();
}
catch (IOException e) {
logger.error( "Could not close config file" + configFilename,e );
}
}
}
return this;
}
public void writePropertiesToFile() {
//saves the current properties to file. Overwrites the existing properties.
//Properties props = new Properties(); //a list of properties
OutputStream outStrm = null;
logger.info("Writing default flag config properties.");
System.out.println("Panel size x = " + xPanelSizeStg );
try {
outStrm = new FileOutputStream( configFilename );
// save properties to file, include a header comment
this.store(outStrm, "This is the Server configuration file");
} catch (IOException io) {
logger.error( "The file :{0} could not be opened", configFilename,io);
} finally {
if (outStrm!= null) {
try {
outStrm.close();
} catch (IOException e) {
logger.error("The file :{0} could not be closed", configFilename, e);
}
}
}
}
}
I have relied on the Properties parent to initiate Properties which I have accessed with "this". So now main looks like:
public static void main(String[] args) {
ClientProperties p = new ClientProperties();
p.readPropertiesFromFile();
String txt = p.getProperty("xPanelsize");
System.out.println("Panel size x = " + txt );
p.setProperty("xPanelsize","64");
p.writePropertiesToFile();
}
The class now hides all the admin around reading, writing and files. Crucially it avoids writing a setter/getter for each property (and I have a lot more properties than the two shown here). That is what I had in my first version.
Thanks for your help. It would have taken me a long time to figure all this out by myself.
You should probably need to create a getter for your 'props' object.
public Properties getProps()
{
return props;
}
And you will be able to invoke it like this:
p.getProps().setProperty("key", "value");
Or, if you are planning to make your ClientProperties class a children of Properties class, then you will need to use 'extends' and you would be able to invoke it by using
p.setProperty("key", "value");
And in this case you wouldn't need any Properties object in your class' fields.
This is my suggestion for your example.
First, you don't need to be edit again the properties in your writePropertiesToFile method like this:
public void writePropertiesToFile() {
// saves the current properties to file. Overwrites the existing properties.
// Properties props = new Properties(); // a list of properties
OutputStream outStrm = null;
logger.info("Writing default flag config properties.");
logger.debug("Panel size x = " + xPanelSizeStg);
try {
outStrm = new FileOutputStream(configFilename);
// set the properties values
//props.setProperty("xPanelsize", xPanelSizeStg);
//props.setProperty("yPanelsize", yPanelSizeStg);
// save properties to file, include a header comment
props.store(outStrm, "This is the Server configuration file");
} catch (IOException io) {
logger.error("The file :{0} could not be opened", configFilename, io);
} finally {
if (outStrm != null) {
try {
outStrm.close();
} catch (IOException e) {
logger.error("The file :{0} could not be closed", configFilename, e);
}
}
}
}
Then, you just create a setProperty method using the global variable -props- in the class.
private void setProperty(String key, String value) {
this.props.setProperty(key, value);
}
If your property file looks like image below:
The value of xPanelsize should be changed after running application.
public static void main(String[] args) {
Properties props = null;
ClientProperties p = new ClientProperties();
props = p.readPropertiesFromFile();
String xPanelsize = props.getProperty("xPanelsize");
System.out.println("Panel size x = " + xPanelsize);
p.setProperty("xPanelsize", "64"); // method not found error
p.writePropertiesToFile();
props = p.readPropertiesFromFile();
xPanelsize = props.getProperty("xPanelsize");
System.out.println("So, now the Panel size x = " + xPanelsize);
}
The debug message is,
The property file contents will be:
Here is full source:
package stackoverflow;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Properties;
import java.util.logging.Level;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/* Defines key properties of the iFlag application.
* Methods read and write properties.
*/
public class ClientProperties {
Logger logger = LoggerFactory.getLogger(ClientProperties.class.getSimpleName());
private Properties props;
private String xPanelSizeStg;
private String yPanelSizeStg;
private int xPanelSize;
private int yPanelSize;
// private static String configFilename =
// "/home/myname/config/client_config.properties";
private static String configFilename = "resource/client_config.properties";
public ClientProperties() {
props = new Properties();
xPanelSizeStg = "32";
yPanelSizeStg = "32";
xPanelSize = 32;
yPanelSize = 32;
}
/**
* Reads properties from file Reads the current properties object from file. The
* file is stored in /home/mimibox/config/flag_config.properties
*/
public Properties readPropertiesFromFile() {
// create and load default properties
InputStream input = null;
logger.trace("Read flag config properties.");
try {
input = new FileInputStream(configFilename);
// load a properties file from class path, inside static method
props.load(input);
// get the property values and save
xPanelSizeStg = props.getProperty("xPanelsize", "32");
yPanelSizeStg = props.getProperty("yPanelsize", "32");
} catch (IOException ex) {
logger.error("Could not open config file" + configFilename, ex);
} finally {
if (input != null) {
try {
input.close();
} catch (IOException e) {
logger.error("Could not close config file" + configFilename, e);
}
}
}
return props;
}
/**
* Writes properties to file Writes the current properties object to file. The
* file is stored in /home/mimibox/config/flag_config.properties
*/
public void writePropertiesToFile() {
// saves the current properties to file. Overwrites the existing properties.
// Properties props = new Properties(); // a list of properties
OutputStream outStrm = null;
logger.info("Writing default flag config properties.");
logger.debug("Panel size x = " + xPanelSizeStg);
try {
outStrm = new FileOutputStream(configFilename);
// set the properties values
//props.setProperty("xPanelsize", xPanelSizeStg);
//props.setProperty("yPanelsize", yPanelSizeStg);
// save properties to file, include a header comment
props.store(outStrm, "This is the Server configuration file");
} catch (IOException io) {
logger.error("The file :{0} could not be opened", configFilename, io);
} finally {
if (outStrm != null) {
try {
outStrm.close();
} catch (IOException e) {
logger.error("The file :{0} could not be closed", configFilename, e);
}
}
}
}
private void setProperty(String key, String value) {
this.props.setProperty(key, value);
}
public int getxPanelSize() {
return this.xPanelSize;
}
public void setxPanelSize(int xPanelSize) {
this.xPanelSize = xPanelSize;
}
public int getyPanelSize() {
return yPanelSize;
}
public void setyPanelSize(int yPanelSize) {
this.yPanelSize = yPanelSize;
}
public static void main(String[] args) {
Properties props = null;
ClientProperties p = new ClientProperties();
props = p.readPropertiesFromFile();
String xPanelsize = props.getProperty("xPanelsize");
System.out.println("Panel size x = " + xPanelsize);
p.setProperty("xPanelsize", "64"); // method not found error
p.writePropertiesToFile();
props = p.readPropertiesFromFile();
xPanelsize = props.getProperty("xPanelsize");
System.out.println("So, now the Panel size x = " + xPanelsize);
}
}
I have got couple of Jersey REST Web services say SendPassword and ResetPassword whose purpose is to send email .
For sending email , i have configured a properties file under tomcat and all this works fine
The code of the SendPassword.java is somewhat this way
#Path("/sendpassword")
public class SendPassword {
#GET
#Produces("application/json")
public String sendPasswordToEmail(#QueryParam("empid") String empid)
throws JSONException
{
try {
SendEmailUtility.sendmail("weqw","2312");
}
catch(Exception e)
{
}
}
SendEmailUtility.java
public class SendEmailUtility
{
public static String sendmail(String sendemalto,String generatedpwd) throws IOException {
String result = "fail";
File configDir = new File(System.getProperty("catalina.base"), "conf");
File configFile = new File(configDir, "email.properties");
InputStream stream = new FileInputStream(configFile);
Properties props_load = new Properties();
props_load.load(stream);
final String username = props_load.getProperty("username");
final String password = props_load.getProperty("password");
Properties props_send = new Properties();
props_send.put("mail.smtp.auth","true");
props_send.put("mail.smtp.starttls.enable","true");
Transport.send(message);
// Some code to send email
result = "success";
} catch (MessagingException e) {
result = "fail";
e.printStackTrace();
}
return result;
}
}
As you can see i am reading the properties file for every call of the websercice
(As reading operation is somewhat costly) , Is there any way to resolve this ??
Could you please let me know whats the best approach to handle this.
Thanks in advance .
There are few ways to do this the one way of doing it is to make the props_load a private static member of the class and call it like this
public class SendEmailUtility
{
private static Properties props;
private static Properties getProperties() {
if (props == null) {
File configDir = new File(System.getProperty("catalina.base"), "conf");
File configFile = new File(configDir, "email.properties");
InputStream stream = new FileInputStream(configFile);
props = new Properties();
props.load(stream);
}
return props;
}
public static String sendmail(String sendemalto,String generatedpwd) throws IOException {
String result = "fail";
Properties props_load = getProperties();
final String username = props_load.getProperty("username");
final String password = props_load.getProperty("password");
Properties props_send = new Properties();
props_send.put("mail.smtp.auth","true");
props_send.put("mail.smtp.starttls.enable","true");
Transport.send(message);
// Some code to send email
result = "success";
} catch (MessagingException e) {
result = "fail";
e.printStackTrace();
}
return result;
}
}
The other design I would suggest is to make an email service class like EmailSender or EmailService and then inject it into SendPassword class
#Path("/sendpassword")
public class SendPassword {
#Autowired
EmailService emailService;
#GET
#Produces("application/json")
public String sendPasswordToEmail(#QueryParam("empid") String empid)
throws JSONException
{
I would recommend using resource bundle, which does not need InputStream
create a properties file and put directly inside your packages along with your java code
example folder structure
com
- preethi
-SendPassword.java
-email.properties
Then you can code like
ResourceBundle props_load = ResourceBundle.getBundle("com.preethi.email");
final String username = props_load.getString("username");
This way you don't have to worry about opening and closing the stream or file path
You could use a lazy-getter to fetch and cache the Properties object.
private static Properties props;
private static Properties getProperties() {
if (props == null) {
File configDir = new File(System.getProperty("catalina.base"), "conf");
File configFile = new File(configDir, "email.properties");
InputStream stream = new FileInputStream(configFile);
props = new Properties();
props.load(stream);
}
return props;
}
Each time you want to use the Properties, call getProperties(). It will cache it the first time it's called. Each subsequent call will just return the cached object.
Note: This example does not catch any exceptions.
I have a haddop job that its output should be written to HBase. I do not really needs reducer, the kind of row I would like to insert is determined in the Mapper.
How can I use TableOutputFormat to achieve this? From all the examples I have seen the assumption is that the reducer is the one creating the Put, and that TableMapper is just for reading from HBase table.
In my case the input is HDFS the output is Put to specific table, I cannot find anything in TableMapReduceUtil that can help me with that either.
Is there any example out there that can help me with that?
BTW, I am using the new Hadoop API
This is the example of reading from file and put all lines into Hbase. This example is from "Hbase: The definitive guide" and you can find it on repository. To get it just clone repo on your computer:
git clone git://github.com/larsgeorge/hbase-book.git
In this book you can also find all the explanations about the code. But if something is incomprehensible for you, feel free to ask.
` public class ImportFromFile {
public static final String NAME = "ImportFromFile";
public enum Counters { LINES }
static class ImportMapper
extends Mapper<LongWritable, Text, ImmutableBytesWritable, Writable> {
private byte[] family = null;
private byte[] qualifier = null;
#Override
protected void setup(Context context)
throws IOException, InterruptedException {
String column = context.getConfiguration().get("conf.column");
byte[][] colkey = KeyValue.parseColumn(Bytes.toBytes(column));
family = colkey[0];
if (colkey.length > 1) {
qualifier = colkey[1];
}
}
#Override
public void map(LongWritable offset, Text line, Context context)
throws IOException {
try {
String lineString = line.toString();
byte[] rowkey = DigestUtils.md5(lineString);
Put put = new Put(rowkey);
put.add(family, qualifier, Bytes.toBytes(lineString));
context.write(new ImmutableBytesWritable(rowkey), put);
context.getCounter(Counters.LINES).increment(1);
} catch (Exception e) {
e.printStackTrace();
}
}
}
private static CommandLine parseArgs(String[] args) throws ParseException {
Options options = new Options();
Option o = new Option("t", "table", true,
"table to import into (must exist)");
o.setArgName("table-name");
o.setRequired(true);
options.addOption(o);
o = new Option("c", "column", true,
"column to store row data into (must exist)");
o.setArgName("family:qualifier");
o.setRequired(true);
options.addOption(o);
o = new Option("i", "input", true,
"the directory or file to read from");
o.setArgName("path-in-HDFS");
o.setRequired(true);
options.addOption(o);
options.addOption("d", "debug", false, "switch on DEBUG log level");
CommandLineParser parser = new PosixParser();
CommandLine cmd = null;
try {
cmd = parser.parse(options, args);
} catch (Exception e) {
System.err.println("ERROR: " + e.getMessage() + "\n");
HelpFormatter formatter = new HelpFormatter();
formatter.printHelp(NAME + " ", options, true);
System.exit(-1);
}
return cmd;
}
public static void main(String[] args) throws Exception {
Configuration conf = HBaseConfiguration.create();
String[] otherArgs =
new GenericOptionsParser(conf, args).getRemainingArgs();
CommandLine cmd = parseArgs(otherArgs);
String table = cmd.getOptionValue("t");
String input = cmd.getOptionValue("i");
String column = cmd.getOptionValue("c");
conf.set("conf.column", column);
Job job = new Job(conf, "Import from file " + input + " into table " + table);
job.setJarByClass(ImportFromFile.class);
job.setMapperClass(ImportMapper.class);
job.setOutputFormatClass(TableOutputFormat.class);
job.getConfiguration().set(TableOutputFormat.OUTPUT_TABLE, table);
job.setOutputKeyClass(ImmutableBytesWritable.class);
job.setOutputValueClass(Writable.class);
job.setNumReduceTasks(0);
FileInputFormat.addInputPath(job, new Path(input));
System.exit(job.waitForCompletion(true) ? 0 : 1);
}
}`
You just need to make the mapper output the pair. OutputFormat only specifies how to persist the output key-values. It does not necessarily mean that the key values come from reducer.
You would need to do something like this in the mapper:
... extends TableMapper<ImmutableBytesWritable, Put>() {
...
...
context.write(<some key>, <some Put or Delete object>);
}