How to open a code or text file online
Three steps, a few seconds, no software.
Open your .JNLP file
Drop it on the box, choose it from your device, or paste the text straight in.
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Your .JNLP file opens neatly formatted with line numbers.
Search, copy or download
Search the text, jump to any line, then copy what you need or download a clean copy.
What is a .JNLP file?
Plain text that programs, servers and people write every day.
A JNLP file is a small XML launcher for Java Web Start that tells Java which application JAR files to download from a server and run. The technology is discontinued. Oracle removed Java Web Start in Java 11 (2018), so on a modern system double-clicking a JNLP file does nothing. To run a legacy JNLP application today, install the free OpenWebStart.
Programs that open .JNLP files
| Full name | Java Network Launch Protocol file |
|---|---|
| Developer | Sun Microsystems (later Oracle); spec JSR-56 |
| First released | 2001 (Java Web Start, J2SE 1.3.1/1.4 era; standardized as JSR-56) |
| Category | Text & Code |
| MIME type | application/x-java-jnlp-file |
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Frequently asked questions
Is my .JNLP file uploaded anywhere?
No. The file is read and highlighted for you.
Why do some characters look wrong (é, ł)?
That usually means the file was saved in one encoding and opened in another. We detect UTF-8, UTF-16 and the Windows-1250/1252 code pages automatically and show which one was used.
Can it handle huge log files?
Yes, up to 50 MB. Only the lines on screen are drawn, so scrolling stays smooth. Syntax colours are switched off for files over 1.5 MB to keep things fast.
How do the log level filters work?
We find levels like ERROR, WARN, INFO and DEBUG on each line. Lines without a level, such as stack traces, stay with the entry above them, so filtering to errors keeps the full trace.
Can I edit the file?
This is a viewer. To change code, download it or copy it into your editor. Converting encodings and line endings is planned.
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