DZone Snippets: debug code

Using ruby-debug

jrobertson (James Robertson) — Wed, 16 Jan 2008 11:06:46 GMT

Uses ruby-debug to step through a script at run-time. keywords: Debugger.start, debug_method



...



require 'ruby-debug'



class ProjectX_handler

  def invoke(project, method, params)

    Debugger.start {

    h = Hash.new

    h['car_log'] = Car_log_handler.new

    h['recordx'] = RecordX_handler.new

    h['mrecord'] = MRecord_handler.new

    h['fileop'] = FileOp_handler.new

    h['rx2projectx'] = RX2ProjectX_handler.new

    h['blog'] = Blog_handler.new

  

    h[project].invoke(method, params)

    }

  end

  debug_method :invoke

end



...

at the (rdb:1) prompt you can type help for information on debugger commands. Commands I've tried so far are
'step' (move to the next statement),
list (show the current line of execution and the fragment of code which the debugger is current analysing),
'break projectx_handler.rb:29' (go to the following line within the file specified, when execution is continued,
'continue' (resume normal code execution),
'v l' (display local variables), and
'p' (evaluate expression and print it's value)

Note: Ruby-debug would not install properly on *Ubuntu 7.10, but installed fine on Ubuntu 7.4 and Gentoo 2007.1.
* - extconf.rb:1:in `require': no such file to load -- mkmf (LoadError)
from extconf.rb:1

*update 12 Feb*
found out that I needed the Ruby dev header files to install the Ruby-debug gem. Here's how sudo apt-get install ruby1.8-dev

dbg - debuging routine

uten (ksflock) — Sat, 20 Oct 2007 07:31:06 GMT

A handy little routine to debug autoit scripts



dbg("Log this message")

Func dbg($msg, $error=@error, $extended=@extended, $ScriptLineNumber=@ScriptLineNumber)

    Local $out = "(" & $ScriptLineNumber & ")(" & $error & ")(" & $extended & ") := " & $msg 

    ;Output to application attaching a console to the script engine

    ConsoleWrite($msg & @CRLF)

    ;Output to debugger (dbgview.exe)

    DllCall("kernel32.dll", "none", "OutputDebugString", "str", $out)

EndFunc

PHP Debugging

mjlintz () — Fri, 10 Aug 2007 19:57:34 GMT

// Place at the top of script being developed



error_reporting(E_ALL);

JavaScript var_dump (Mark 2)

singpolyma () — Thu, 12 Jul 2007 15:29:58 GMT

Same as var_dump for PHP, but for JavaScript. Useful if you do not have Firebug.

A typical useage:

document.write(var_dump(ANY-JS-VAR,'html'));



     function var_dump(data,addwhitespace,safety,level) {

        var rtrn = '';

        var dt,it,spaces = '';

        if(!level) {level = 1;}

        for(var i=0; i           spaces += '   ';

        }//end for i        if(typeof(data) != 'object') {

           dt = data;

           if(typeof(data) == 'string') {

              if(addwhitespace == 'html') {

                 dt = dt.replace(/&/g,'&');

                 dt = dt.replace(/>/g,'>');

                 dt = dt.replace(/              }//end if addwhitespace == html

              dt = dt.replace(/\"/g,'\"');

              dt = '"' + dt + '"';

           }//end if typeof == string

           if(typeof(data) == 'function' && addwhitespace) {

              dt = new String(dt).replace(/\n/g,"\n"+spaces);

              if(addwhitespace == 'html') {

                 dt = dt.replace(/&/g,'&');

                 dt = dt.replace(/>/g,'>');

                 dt = dt.replace(/              }//end if addwhitespace == html

           }//end if typeof == function

           if(typeof(data) == 'undefined') {

              dt = 'undefined';

           }//end if typeof == undefined

           if(addwhitespace == 'html') {

              if(typeof(dt) != 'string') {

                 dt = new String(dt);

              }//end typeof != string

              dt = dt.replace(/ /g," ").replace(/\n/g,"
");

           }//end if addwhitespace == html

           return dt;

        }//end if typeof != object && != array

        for (var x in data) {

           if(safety && (level > safety)) {

              dt = '*RECURSION*';

           } else {

              try {

                 dt = var_dump(data[x],addwhitespace,safety,level+1);

              } catch (e) {continue;}

           }//end if-else level > safety

           it = var_dump(x,addwhitespace,safety,level+1);

           rtrn += it + ':' + dt + ',';

           if(addwhitespace) {

              rtrn += '\n'+spaces;

           }//end if addwhitespace

        }//end for...in

        if(addwhitespace) {

           rtrn = '{\n' + spaces + rtrn.substr(0,rtrn.length-(2+(level*3))) + '\n' + spaces.substr(0,spaces.length-3) + '}';

        } else {

           rtrn = '{' + rtrn.substr(0,rtrn.length-1) + '}';

        }//end if-else addwhitespace

        if(addwhitespace == 'html') {

           rtrn = rtrn.replace(/ /g," ").replace(/\n/g,"
");

        }//end if addwhitespace == html

        return rtrn;

     }//end function var_dump

Debug logs in the database

koke24 (Koke) — Wed, 30 May 2007 16:59:19 GMT

How to log things in the database

Create the table:



create table TMP_LOG (HORA date, ENTRADA varchar(4000));

Write the things I need to the table:



INSERT INTO TMP_LOG (HORA, ENTRADA) VALUES(SYSDATE, 

  'V_NOM_DESTINATARIO1: '||V_NOM_DESTINATARIO1||', V_DOM_DESTINATARIO1: '||V_DOM_DESTINATARIO1||

  ', P_NOM_DESTINATARIO_2: '||P_NOM_DESTINATARIO_2||', P_DOM_DESTINATARIO_2: '||P_DOM_DESTINATARIO_2||

  ', B_DESTINATARIO: '||B_DESTINATARIO||

  ', V_NOM_DESTINATARIO2: '||V_NOM_DESTINATARIO2||', V_DOM_DESTINATARIO2: '||V_DOM_DESTINATARIO2);

Consult the things written:



select * from tmp_log order by hora desc;

Dont forget to drop it at the end:



drop table TMP_LOG;

Java: log4j Initialization Example

thitiv (Thiti V. Sintopchai) — Mon, 14 May 2007 09:44:45 GMT

// Initialization for Basic Console Output
// Ref: http://logging.apache.org/log4j/docs/manual.html



 import com.foo.Bar;



 // Import log4j classes.

 import org.apache.log4j.Logger;

 import org.apache.log4j.BasicConfigurator;



 public class MyApp {



   // Define a static logger variable so that it references the

   // Logger instance named "MyApp".

   static Logger logger = Logger.getLogger(MyApp.class);



   public static void main(String[] args) {



     // Set up a simple configuration that logs on the console.

     BasicConfigurator.configure();



     logger.setLevel(Level.DEBUG); // optional if log4j.properties file not used

     // Possible levels: TRACE, DEBUG, INFO, WARN, ERROR, and FATAL



     logger.info("Entering application.");

     Bar bar = new Bar();

     bar.doIt();

     logger.info("Exiting application.");

   }

 }

Java DOM: Printing the Content of a Node

thitiv (Thiti V. Sintopchai) — Mon, 14 May 2007 09:19:05 GMT



    try

    {

      // Set up the output transformer

      TransformerFactory transfac = TransformerFactory.newInstance();

      Transformer trans = transfac.newTransformer();

      trans.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "yes");

      trans.setOutputProperty(OutputKeys.INDENT, "yes");



      // Print the DOM node



      StringWriter sw = new StringWriter();

      StreamResult result = new StreamResult(sw);

      DOMSource source = new DOMSource(node);

      trans.transform(source, result);

      String xmlString = sw.toString();



      System.out.println(xmlString);

    }

    catch (TransformerException e)

    {

      e.printStackTrace();

    }

Mostar los resultados de un cursor

koke24 (Koke) — Fri, 04 May 2007 10:04:24 GMT

Esto muestra los resultados de un cursor en la ventana de pruebas del SQL Developer

Declaración de las variables



c1 varchar2(200);

c2 varchar2(200);

c3 varchar2(200);

Código en sí



fetch v_Return into c1, c2, c3;

loop

  EXIT WHEN v_Return%NOTFOUND;

  DBMS_OUTPUT.PUT_LINE(c1||', '||c2||', '||c3);

  fetch v_Return into c1, c2, c3;

end loop;

close v_Return;

Ejemplo del código completo:



DECLARE

  PVCOD_DESPACHO NUMBER;

  PVCOD_IDIOMA VARCHAR2(200);

  v_Return PG_SGIE_Types.cursor_type;

  c1 varchar2(200);

  c2 varchar2(200);

  c3 varchar2(200);

BEGIN

  PVCOD_DESPACHO := 2792;

  PVCOD_IDIOMA := '1';



  v_Return := FU_LISTAENVIOSDESPACHO(

    PVCOD_DESPACHO => PVCOD_DESPACHO,

    PVCOD_IDIOMA => PVCOD_IDIOMA

  );

  -- Modify the code to output the variable

  --DBMS_OUTPUT.PUT_LINE('v_Return = ' || v_Return);

  

  fetch v_Return into c1, c2, c3;

  loop

    EXIT WHEN v_Return%NOTFOUND;

    DBMS_OUTPUT.PUT_LINE(c1||', '||c2||', '||c3);

    fetch v_Return into c1, c2, c3;

  end loop;

  close v_Return;

END;

Which class file is loaded by the classloader ?

nivek (Kevin Gaudin) — Fri, 23 Mar 2007 11:38:37 GMT

When using lots of third-party libraries, one problem might be that 2 of them package different versions of the same class, producing errors when method version conflicts happen.

Here is a simple way to know the exact location used by the classloader to get your class :



URL myClassURL = MyMysteryClass.class.getProtectionDomain().getCodeSource().getLocation();

Tomcat debug

Mickael (Mickael) — Wed, 06 Dec 2006 18:25:59 GMT

// description of your code here
Parametre de conf pour lancer un tomcat en debug afin de se connecter a distance sur le port 8000



Xdebug -Xrunjdwp:transport=dt_socket,adress=8000,server=y,suspend=n