Solved

Ubuntu Java: How to run Linux shell scipt from Java program and fetch back its output

Posted on 2009-07-14
8
530 Views
Last Modified: 2012-05-07
Hi: I am using Java (HTTPUnit) in Linux machine. I am using HTTPUnit multi thread to visit a web application (Hibernate, Spring, tomcat, mysql). Experts in this forum give me the script to see Tomcat JVM memory consumption. Now when I use HTTPUnit to visit a page, then I want to check memory usage by the program themself. And see how much memory consumption it takes. If the memory consumption is bigger, I could write it to some file. My question is from Java program how to run a linux script and how to get output back.

The script is as follows: It could be stored in some executable file called checkTomcatJVM.sh.

ps aux | awk '{print $4"\t"$11}' | sort | uniq -c | awk '{print $2" "$1" "$3}' | grep java
0
Comment
Question by:JianJunShen
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
8 Comments
 
LVL 26

Expert Comment

by:ksivananth
ID: 24848897
you can use the Runtime class from java to get the total memory and freememory!

check Runtime.freeMemory()
Runtime.totalMemory
0
 
LVL 6

Expert Comment

by:jwenting
ID: 24848934
Use ProcessBuilder to execute the external process.
Wait for the process to complete, and capture its output stream.
0
 
LVL 14

Expert Comment

by:flob9
ID: 24848936
Runtime.getRuntime().exec(new String[] {"script","param"});
0
Optimize your web performance

What's in the eBook?
- Full list of reasons for poor performance
- Ultimate measures to speed things up
- Primary web monitoring types
- KPIs you should be monitoring in order to increase your ROI

 

Author Comment

by:JianJunShen
ID: 24848983
Runtime.getRuntime().exec(new String[] {"script","param"});

This sounds a good solution to run script. But how to fetch output?
0
 
LVL 14

Accepted Solution

by:
flob9 earned 500 total points
ID: 24849040
Something like this :

Process proc = Runtime.getRuntime().exec(new String[] {"script","param"});

byte[] buff = new byte[1024];

InputStream out = proc.getInputStream();
int nb = out.read(buff);


But, as mentionned before, calling external process for this purpose is quite dirty.
0
 

Author Comment

by:JianJunShen
ID: 24849192
Oh; sorry , I push the wrong button. Now the excellent answer would be closed. My mistake.
0
 

Author Closing Comment

by:JianJunShen
ID: 31603225
Excellent answer and very fast.
0
 
LVL 92

Expert Comment

by:objects
ID: 24854763
you need to read in a loop to ensure you get all output written to stdout


http://helpdesk.objects.com.au/java/runtime-exec-locks-up
0

Featured Post

Optimize your web performance

What's in the eBook?
- Full list of reasons for poor performance
- Ultimate measures to speed things up
- Primary web monitoring types
- KPIs you should be monitoring in order to increase your ROI

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Introduction This article is the last of three articles that explain why and how the Experts Exchange QA Team does test automation for our web site. This article covers our test design approach and then goes through a simple test case example, how …
In this post we will learn how to connect and configure Android Device (Smartphone etc.) with Android Studio. After that we will run a simple Hello World Program.
Viewers will learn about if statements in Java and their use The if statement: The condition required to create an if statement: Variations of if statements: An example using if statements:
Viewers will learn how to properly install Eclipse with the necessary JDK, and will take a look at an introductory Java program. Download Eclipse installation zip file: Extract files from zip file: Download and install JDK 8: Open Eclipse and …

617 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question