Tuesday, 3 October 2017

Talend Console logs to file

Redirecting Talend Console logs to file

Talend Open studio for data integration does not have any component to redirect console trace to a file. This blog post provides the solution for Redirecting Talend Console logs to file and is very easy to follow and extend. In previous article logging-using-talend we have seen how to customize Talend logs. This article shows how to redirect Talend console logs to file. In talend exchange, there is a custom component to perform similar job.


Redirecting Talend console logs is required by almost all Talend projects. This is very easy to implement in talend. Use tJava component at the start of any job and enter following lines into it.

Redirecting Talend Console logs

Redirecting Talend Console logs

java.io.File folder = new java.io.File("_logs/");
if (!folder.exists()) {
if (folder.mkdir()) {
System.out.println("Directory is created!");

else {
System.out.println("Failed to create directory!");
java.io.File logFile = new java.io.File("_log/"+projectName+"_.log");
java.io.PrintStream ts = new java.io.PrintStream(new java.io.FileOutputStream(logFile));

After executing the job, above code creates a flat file with "projectName.log" and starts writing data which appears on the console. You can create a new file at each execution by post/pre fixing with the time stamp in the file name or use following code. Attached image shows

java.io.File file = new java.io.File(projectName+"_"+TalendDate.getDate("CCYYMMDDhhmmss")+".log");

projectName is the variable name provided by the Talend and you can get the postfix date stamp by another variable TalendDate.getDate("CCYY-MM-DD hh:mm:ss"). Remove all the special characters in the time stamp. ProjectName can also be replaced by another global variable jobName.

After successfully executing this job, you can see ProjectName_TimeStamp.log  file is created in the root folder of Talend. This file contains complete console stack trace.


 Drawback of implementing this strategy is that, it will not print or display anything on the console while using IDE or independent execution. This becomes difficult when developer is developing or debugging the job. Because, it is an extra effort for a developer to open a file every time to find out whether the job is executed successfully and generated error or not.

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