Is DataMatrix support UTF8 or ISO-8859-2?

Question

I have problem with Barcode4J and generation DataMatrix with ISO-8859-2 characters in message.
Below example use of barcode4j (version 2.1.0) from command line. As You can see when i use message "żaba" i get error Message contains characters outside ISO-8859-1 encoding. Is DataMatrix specification support ISO-8859-1 only or something is missing in Barcode4J ?

java -cp build/barcode4j.jar:lib/avalon-framework-4.2.0.jar:lib/commons-cli-1.0.jar org.krysalis.barcode4j.cli.Main -s datamatrix "żaba"                           
Exception in thread "main" java.lang.IllegalArgumentException: Message contains characters outside ISO-8859-1 encoding.
 at org.krysalis.barcode4j.impl.datamatrix.DataMatrixHighLevelEncoder$EncoderContext.<init>(DataMatrixHighLevelEncoder.java:199)
 at org.krysalis.barcode4j.impl.datamatrix.DataMatrixHighLevelEncoder.createEncoderContext(DataMatrixHighLevelEncoder.java:171)
 at org.krysalis.barcode4j.impl.datamatrix.DataMatrixHighLevelEncoder.encodeHighLevel(DataMatrixHighLevelEncoder.java:119)
 at org.krysalis.barcode4j.impl.datamatrix.DataMatrixLogicImpl.generateBarcodeLogic(DataMatrixLogicImpl.java:50)
 at org.krysalis.barcode4j.impl.datamatrix.DataMatrixBean.generateBarcode(DataMatrixBean.java:128)
 at org.krysalis.barcode4j.impl.ConfigurableBarcodeGenerator.generateBarcode(ConfigurableBarcodeGenerator.java:174)
 at org.krysalis.barcode4j.cli.Main.handleCommandLine(Main.java:164)
 at org.krysalis.barcode4j.cli.Main.main(Main.java:86)

Answer 1

As is described here, Barcode4J only currently supports the default character set defined by the DataMatrix specification (ISO-8859-1). Support for ECI hasn't been implemented for DataMatrix, yet. You can, however, encode binary messages by encoding a byte stream as an RFC 2397 data URL. That byte stream could be a string encoded using UTF-8. The drawback: the reader might not be able to interpret the data correctly.