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Thread: getProcessCPUTime()

  1. #1
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    Default getProcessCPUTime()

    Hi.
    What is the error at line 42?

    import java.io.*;
    import java.util.*;
    import com.sun.management.OperatingSystemMXBean;
    import java.lang.management.ManagementFactory;
    import java.lang.System;
     
        public class sysinfoHooshi{
     
    	public static void prt(String s){System.out.print(s);}
    	public static void main(String args[]) throws Exception{
    		int k = 10;//k recent pieces of info will be maintained
     
    		OperatingSystemMXBean osBean =
    		 (com.sun.management.OperatingSystemMXBean)ManagementFactory.getOperatingSystemMXBean();
    		class Info{			
    			public String name;
    			public String version;
    			public String arch;
    			long CPUSpeed;
    		};
    		Info info =  new Info();
    		Info[] queue = new Info[100];
     
    		int pos = 1;
     
    		Date d = new Date();
    		long start = d.getTime();
     
    		while(true){
    			long time = d.getTime();
    			if( (start-time)%3 == 0 )
    			{
    				queue[pos].name = System.getProperty("os.name");
    				System.out.println( queue[pos].name);
    				queue[pos].version = System.getProperty("os.version");
    				queue[pos].arch = System.getProperty("os.arch");
    				pos++;
    			}
     
    		}
     
    		info.CPUSpeed = OperatingSystemMXBean.getProcessCPUTime();//javac ERROR!!
     
     
     
    	} // end main
       }// end class date

  2. #2
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    Default Re: getProcessCPUTime()

    You tell us. What is the error at line 42?
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  3. #3
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    Default Re: getProcessCPUTime()

    My terminal screen reads: (I am on ubuntu 12.04 LTS):
    ~$ javac sysinfoHooshi.java
    sysinfoHooshi.java:42: cannot find symbol
    symbol : method getProcessCPUTime()
    location: interface com.sun.management.OperatingSystemMXBean
    info.CPUSpeed = OperatingSystemMXBean.getProcessCPUTime();
    ^
    1 error
    But I apparently have imported that. Isn't Java 'import' = C++ using?

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    Default Re: getProcessCPUTime()

    One problem I see is the following:
    Info[] queue = new Info[100];
    ...
    info.CPUSpeed = ... ;
    What do you think is going to happen here?

  5. #5
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    Default Re: getProcessCPUTime()

    Quote Originally Posted by hooshdar3 View Post
    But I apparently have imported that. Isn't Java 'import' = C++ using?
    Take a look at the API: OperatingSystemMXBean (Java Platform SE 8 )

    That class does not contain that method. In fact, it doesn't contain any static methods, which is how you're trying to call it.

    --- Update ---

    Quote Originally Posted by Cornix View Post
    One problem I see is the following:
    Info[] queue = new Info[100];
    ...
    info.CPUSpeed = ... ;
    What do you think is going to happen here?
    This is what he thinks is going to happen:

    class Info{			
    			public String name;
    			public String version;
    			public String arch;
    			long CPUSpeed;
    		};
    		Info info =  new Info();

    The info.CPUSpeed isn't really wrong, although the setup is a little strange. The problem is in the right side of that line.
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    Default Re: getProcessCPUTime()

    Quote Originally Posted by KevinWorkman View Post
    Take a look at the API: OperatingSystemMXBean (Java Platform SE 8 )

    That class does not contain that method. In fact, it doesn't contain any static methods, which is how you're trying to call it.

    --- Update ---



    This is what he thinks is going to happen:

    class Info{			
    			public String name;
    			public String version;
    			public String arch;
    			long CPUSpeed;
    		};
    		Info info =  new Info();

    The info.CPUSpeed isn't really wrong, although the setup is a little strange. The problem is in the right side of that line.
    OK.I changed line42 to:

    info.CPUSpeed = ((OperatingSystemMXBean)getOperatingSystemMXBean() ).getProcessCpuTime();
    after the 2nd code snippet on:
    java - get OS-level system information - Stack Overflow

    But I get more errors
    (I have also imported java.lang.management.OperatingSystemMXBean with
    import java.lang.management.OperatingSystemMXBean;
    )
    Last edited by hooshdar3; July 9th, 2014 at 10:00 AM.

  7. #7
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    Default Re: getProcessCPUTime()

    I'm really not sure what you think that's supposed to do. Answer these questions:

    What functions are in the OperatingSystemMXBean class?

    What *static* functions are in the OperatingSystemMXBean class?

    What function are you trying to access? Are you trying to access it statically?
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    Default Re: getProcessCPUTime()

    Quote Originally Posted by KevinWorkman View Post
    I'm really not sure what you think that's supposed to do. Answer these questions:

    What functions are in the OperatingSystemMXBean class?

    What *static* functions are in the OperatingSystemMXBean class?

    What function are you trying to access? Are you trying to access it statically?
    I want to get CPU speed + Memory usage and maybe other administrating information

  9. #9
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    Default Re: getProcessCPUTime()

    Quote Originally Posted by hooshdar3 View Post
    I want to get CPU speed + Memory usage and maybe other administrating information
    That doesn't answer any of the questions I asked.
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    Default Re: getProcessCPUTime()

    I just wanna use 'getProcessCpuTime()

  11. #11
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    Default Re: getProcessCPUTime()

    Quote Originally Posted by hooshdar3 View Post
    I just wanna use 'getProcessCpuTime()
    Okay, and what class does that belong to?
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    Default Re: getProcessCPUTime()

    Quote Originally Posted by KevinWorkman View Post
    Okay, and what class does that belong to?
    It says it is part of OperatingSystemMXBean interface, but I don't know how to use interfaces

    --- Update ---

    I managed to get itt compiled and run, by adding:
    import com.sun.management.OperatingSystemMXBean;
    .
    .
    .
    OperatingSystemMXBean osBean = (com.sun.management.OperatingSystemMXBean)
    ManagementFactory.getOperatingSystemMXBean();

    info.CPUSpeed = osBean.getProcessCpuTime();

    System.out.println(info.CPUSpeed);
    But I don't know How exactoly to get the CPU frequency.

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    Default Re: getProcessCPUTime()

    Please....What does the function do exactly?I cannot understand the document completely

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    Default Re: getProcessCPUTime()

    Please copy the text of the doc that you don't understand and post it here with your questions about it.
    If you don't understand my answer, don't ignore it, ask a question.

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    Default Re: getProcessCPUTime()

    Quote Originally Posted by Norm View Post
    Please copy the text of the doc that you don't understand and post it here with your questions about it.
    I don't understand what does it mean that the function
    Returns the CPU time used by the process on which the Java virtual machine is running in nanoseconds.
    and what's the use of it

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    Default getSystemCpuload()

    Hi.
    What's wrong with my invokation of getSystemCpuLoad?
    Here is How my code looks like:
    OperatingSystemMXBean osBean = (com.sun.management.OperatingSystemMXBean)
    			ManagementFactory.getOperatingSystemMXBean();
     
    double CPUUtil = ( osBean.getSystemCpuLoad() ) * 100;

    and here is the output from javac:
    $ javac sysinfoHooshi.java
    sysinfoHooshi.java:43: cannot find symbol
    symbol : method getSystemCpuLoad()
    location: interface com.sun.management.OperatingSystemMXBean
    queue[pos].CPUUtil = ( osBean.getSystemCpuLoad() ) * 100;
    ^
    1 error

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    Default Re: getSystemCpuload()

    The code that you show and the error you posted do not belong together.
    Read the error message, it tells you what the problem is:
    queue[pos].CPUUtil = ( osBean.getSystemCpuLoad() ) * 100;
    Is wrong because the variable "queue" is not a known symbol.

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    Default Re: getSystemCpuload()

    Quote Originally Posted by Cornix View Post
    The code that you show and the error you posted do not belong together.
    Read the error message, it tells you what the problem is:

    Is wrong because the variable "queue" is not a known symbol.
    no.'queue' is defined:
    class Info{
    public String name;
    public String version;
    public String arch;
    public double ramUtil;
    public double CPUUtil;
    };

    Info[] queue = new Info[queueSize];

    int pos = 0;

    for(int i=0;i<queueSize;++i)
    queue[i] = new Info();
    the problem is in the RHS of the assignment

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    Default Re: getSystemCpuload()

    Please post your code in code tags.

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    Default Re: getProcessCPUTime()

    Don'r use it if you don't know what its used for.
    If you don't understand my answer, don't ignore it, ask a question.

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    Default Re: getProcessCPUTime()

    Quote Originally Posted by Norm View Post
    Don'r use it if you don't know what its used for.
    But I need to get CPU speed.
    Last edited by hooshdar3; July 14th, 2014 at 09:50 AM.

  22. #22
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    Default Re: getProcessCPUTime()

    I need to get CPU speed.
    Have you asked an internet Search engine how to do that?

    You may have to use JNI to get hardware stats.
    If you don't understand my answer, don't ignore it, ask a question.

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    Default Re: getProcessCPUTime()

    Yes Norm I have. What is JNI and how to use it?

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    Default Re: getProcessCPUTime()

    JNI stands for Java Native Interface. Its an API that allows you to use native libraries.

  25. The Following User Says Thank You to Cornix For This Useful Post:

    hooshdar3 (July 15th, 2014)