BarCode Image Generator in Java

iText is a great Java PDF library. They also have an API for creating barcodes. You don't need to be creating a PDF to use it.

This page has the details on creating barcodes. Here is an example from that site:

BarcodeEAN codeEAN = new BarcodeEAN();
codeEAN.setCodeType(codeEAN.EAN13);
codeEAN.setCode("9780201615883");
Image imageEAN = codeEAN.createImageWithBarcode(cb, null, null);

The biggest thing you will need to determine is what type of barcode you need. There are many different barcode formats and iText does support a lot of them. You will need to know what format you need before you can determine if this API will work for you.

There is also this free API that you can use to make free barcodes in java.

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