OpenCSVIterator

Conveniently wraps com.opencsv.CSVReader from the OpenCSV project in an Iterator

Usage

OpenCSVIterator can be used in plain Java but the main intention is to provide support for Groovy iterator functions. For example, to print each row of a CSV file:

new File('myfile.csv').withReader { fileReader ->
    def csvReader = new CSVReader(fileReader)
    def csvIterator = new OpenCSVIterator(csvReader)
    csvIterator.each { row ->
        println row
    }
}

The returned row object is an immutable Map of strings, mapping row values to column names. Column names and row values are trimmed. Each column must be present in each row, but empty values will not be included in the row map.

Column Names

OpenCSVIterator will read the column names from the first row of the reader. Alternatively, they can be specified as a List or String array:

def withList = new OpenCSVIterator(csvReader, ['field1', 'field2'])
def withArray = new OpenCSVIterator(csvReader, 'field1', 'field2')

The column names can be retrieved from the columns property on the iterator.

Extension

OpenCSVIterator also includes an extension module that add an iterator method directly to CSVReader.

~~Implicit iterator:~~

def csvReader = new CSVReader(reader)
csvReader.each {
    ...
}

From OpenCSV version 3, CSVReader began implementing Iterable and added a new iterator() method which returns an iterator of String[]. As DefaultGroovyMethods is now implemented in Java, there is no way to intercept this call.

Array of column names:

def csvReader = new CSVReader(reader)
csvReader.iterator('column1', 'column2').each {
    ...
}

List of column names:

def csvReader = new CSVReader(reader)
csvReader.iterator(['column1', 'column2']).each {
    ...
}

Get it

OpenCSVIterator can be obtained from Bintray JCenter. Groovy is also required as a dependency of the project.

build.gradle

repositories {
    jcenter()
}

dependencies {
    compile 'com.adjectivecolournoun:opencsv-iterator:2.0.4'
    compile 'org.codehaus.groovy:groovy:3.0.2'
}

pom.xml

<repository>
    <snapshots>
        <enabled>false</enabled>
    </snapshots>
    <id>central</id>
    <name>bintray</name>
    <url>http://jcenter.bintray.com</url>
</repository>

<dependency>
    <groupId>com.adjectivecolournoun</groupId>
    <artifactId>opencsv-iterator</artifactId>
    <version>2.0.4</version>
</dependency>

<dependency>
    <groupId>org.codehaus.groovy</groupId>
    <artifactId>groovy</artifactId>
    <version>3.0.2</version>
</dependency>

Licence

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0