Insert image in iReport using xml datasource

When using an XML file as a datasource for a report designed with iReport-Designer for JasperReports, you sometimes want to add an image, which also should be retrieved from the XML datasource.
For this, we have to first find a way to represent that image in the XML file, and then, interpret it from there and obtain an actual image file inside the report.

• Represent the image in the XML file

In order to represent an image inside an XML file, we have to obtain a string out of it, so we can write that string inside an xml tag. We will use a byte array that represents the image, and encode it using Apache’s Base64 class which provides utility methods for encoding/decoding.

import org.apache.commons.codec.binary.Base64; import org.apache.commons.codec.binary.StringUtils; ... //Obtain an input stream for the image we want to represent in the xml InputStream is = ClassName.class.getResourceAsStream("image.jpg"); //create a byte array of the appropriate size for holding the image bytes byte[] buffer = new byte[is.available()]; //populate the byte array with actual data is.read(buffer); //obtain an encoded string from the byte array, which will be written inside the xml String encodedImgStr = StringUtils.newStringIso8859_1(Base64 .encodeBase64(buffer));

import org.apache.commons.codec.binary.Base64; import org.apache.commons.codec.binary.StringUtils; ... //Obtain an input stream for the image we want to represent in the xml InputStream is = ClassName.class.getResourceAsStream("image.jpg"); //create a byte array of the appropriate size for holding the image bytes byte[] buffer = new byte[is.available()]; //populate the byte array with actual data is.read(buffer); //obtain an encoded string from the byte array, which will be written inside the xml String encodedImgStr = StringUtils.newStringIso8859_1(Base64 .encodeBase64(buffer));

Write the encoded base64 message inside the xml like:
<image><![CDATA[ ... Base64 mess here ... ]]></image></code>

• Read the actual image from the XML file inside iReport
1. inside the report that has the previously created xml file as a datasource, create a String field named "image", which represents the encoded string from the datasource.
2. then create a variable which will interpret this string and transforms it into a ByteArrayInputStream. The variable has java.io.ByteArrayInputStream as a variable class, and as a variable expression:

new ByteArrayInputStream(Base64.decodeBase64(StringUtils.getBytesIso8859_1($F{image})))

new ByteArrayInputStream(Base64.decodeBase64(StringUtils.getBytesIso8859_1($F{image})))

Note! you have to add these imports for the report element
org.apache.commons.codec.binary.Base64
org.apache.commons.codec.binary.StringUtils
and add the commons-codec.jar file to the iReport classpath (Tools->Options->Classpath)

3. create a visual image field which uses the previously created variable as an image expression and java.io.InputStream as the expression class

And you should see the image properly rendered inside the report