README
“The
REFCODES.ORG
codes represent a group of artifacts consolidating parts of my work in the past years. Several topics are covered which I consider useful for you, programmers, developers and software engineers.”
What is this repository for?
This archetype helps processing table like data structures including the processing of CSV
files with records, headers as well as comments whilst supporting Plain old java objects
(POJO
) and simple new Java record
types.
Quick start archetype
Use the refcodes-archetype-alt-csv
archetype to create a bare metal CSV
(CLI
) driven Java
application:
Please adjust
my.corp
with your actual Group-ID andmyapp
with your actual Artifact-ID!
mvn archetype:generate \
-DarchetypeGroupId=org.refcodes \
-DarchetypeArtifactId=refcodes-archetype-alt-csv \
-DarchetypeVersion=3.0.4 \
-DgroupId=my.corp \
-DartifactId=myapp \
-Dversion=1.0-SNAPSHOT
Using the defaults, this will generate a CSV
processing application harnessing the refcodes-tabular
toolkit whilst providing a command line interface by harnessing the refcodes-cli
toolkit.
How do I get set up?
To get up and running, include the following dependency (without the three dots “…”) in your pom.xml
:
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<dependencies>
...
<dependency>
<artifactId>refcodes-tabular</artifactId>
<groupId>org.refcodes</groupId>
<version>3.0.4</version>
</dependency>
...
</dependencies>
The artifact is hosted directly at Maven Central. Jump straight to the source codes at Bitbucket. Read the artifact’s javadoc at javadoc.io.
Code snippets of interest
The below example presumes a type Tupel
being defined with the attributes date
(Date), n1
(int), n2
(int), n3
(int), n4
(int), n5
(int), n6
, (int), jackpot
(float) and currency
(String). An input CSV
file is being read line by line where each line represents a Record
and which’s field are mapped to the Tupel
type. This Tupel
instance then is written (to exemplify writing to an output CSV
file) back to the output CSV
file.
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...
import static org.refcodes.tabular.TabularSugar.*;
import org.refcodes.tabular.CsvRecordReader;
import org.refcodes.tabular.CsvRecordWriter;
import org.refcodes.tabular.Header;
public class SomeClass {
...
public void someMethod(boolean hasHeader) {
...
File theSourceFile = ...
File theDestFile = ...
...
Tupel eTupel;
Header<?> theHeader = headerOf( dateColumn( "date", DateFormat.MIN_DATE_FORMAT.getFormatter() ), intColumn( "n1" ), intColumn( "n2" ), intColumn( "n3" ), intColumn( "n4" ), intColumn( "n5" ), intColumn( "n6" ), floatColumn( "jackpot" ), stringColumn( "currency" ) );
try (CsvRecordReader<?> theCsvReader = theSourceFile != null ? new CsvRecordReader<>( theHeader, theSourceFile, theSourceDelimiter ) : new CsvRecordReader<>( theHeader, new BufferedInputStream( System.in ), theSourceDelimiter )) {
try (CsvRecordWriter<?> theCsvWriter = theDestFile != null ? new CsvRecordWriter<>( theHeader, theDestFile, theDestDelimiter ) : new CsvRecordWriter<>( theHeader, new BufferedOutputStream( System.out ), theDestDelimiter )) {
if ( hasHeader ) {
theCsvReader.readHeader();
theCsvWriter.writeHeader();
}
while ( theCsvReader.hasNext() ) {
eTupel = theCsvReader.nextType( Tupel.class );
theCsvWriter.writeType( eTupel );
}
}
}
...
}
...
}
Note: As said above, the type
Tupel
corresponds to the headertheHeader
in terms of attributes and their types!
An sample of the CSV
file being processed might look as follows:
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date;n1;n2;n3;n4;n5;n6;jackpot;currency
2021-02-24;1;5;13;36;44;46;26529922;EUR
2021-02-17;4;10;25;29;40;48;26362228;EUR
2021-02-10;5;19;21;27;32;46;28438716;EUR
2021-02-03;3;6;10;12;34;47;27384502;EUR
2021-01-27;1;4;15;16;44;45;25298324;EUR
2021-01-20;5;6;11;31;35;42;26535136;EUR
Examples
See the sources of the funcodes-calcsv
and funcodes-waves
command line tools for a demo of this toolkit as well as the source code examples of this artifact.
Contribution guidelines
- Writing tests
- Code review
- Adding functionality
- Fixing bugs
Who do I talk to?
- Siegfried Steiner (steiner@refcodes.org)
Terms and conditions
The REFCODES.ORG
group of artifacts is published under some open source licenses; covered by the refcodes-licensing
(org.refcodes
group) artifact - evident in each artifact in question as of the pom.xml
dependency included in such artifact.