How to use java program in bean pre-processor

Question

The below program reads the XML file and compress into gzip.

I have a couple of questions here.

Can I use the following program directly in JMeter BeanShell pre-processor?
I want to use the output variable as input to JSON request. Is it possible in Jmeter?

Screen shot and details will be appreciated.

public static void main(String[] args) throws Exception {

String line = null; 
String sb = "";
File f=new File("D:\\RetailTransactionLog_9419_001_590.xml");
FileReader fr=new FileReader(f);
BufferedReader br=new BufferedReader(fr);   

while((line=br.readLine())!=null)
{
     sb= sb + line;
}   
br.close();


ByteArrayOutputStream baos = new ByteArrayOutputStream();
GZIPOutputStream gzos = new GZIPOutputStream(baos);
gzos.write(sb.getBytes("UTF-8"));
gzos.close();

String base64CompressedString = Base64.getEncoder().encodeToString(baos.toByteArray());
System.out.println(base64CompressedString);

luludenim luludenim · Accepted Answer · 2016-06-26T16:47:20

Of course, you can put your piece of java code directly in a JMeter BeanShell pre-processor and much more !

Insert you pre-processor component as child of your JSON request (as in my script example in attachment).

You don’t need to import java.io package like BufferedReader, ByteArrayOutputStream, File, FileReader, IOException, Base64…

Remove also the main signature public static void main(String[] args) …

You only have to import "java.util.zip.GZIPOutputStream" (A)

I’ve also replace your System.out.println(base64CompressedString) by log.info(base64CompressedString) just to visualize in the jmeter console your output (B)…

And finally add at the end, the code (C) to reference your result in the variable of your choice ("a" in my example).

You just have to call your variable after with ${a} in your json request like in my JMX script :

Unzip attachments http://uplea.com/dl/9F734367B43FB93 :

"ReadAndCompressMyFile.jmx" under /bin and put "test.xml" under C: or change the path in your code.

I’ve used a dummy sampler instead of your json request.

After running my script, you can see in View Result Tree (Request tab) and in the console, the value of "a" (corresponding to base64CompressedString).

PS : To run my script with the "dummy sampler", you need to add jmeter-plugins-dummy-0.1.jar under /lib/ext of your jmeter directory.

Hope to help you...

How to use java program in bean pre-processor

2 Answers