Recupérer des variables d'environnement

Question

Salut à toute la bande,

Comment peut on recuperer des variables d'environnement en java?
J'ai trouve la fonction System.getProperty mais elle ne concerne que les vraibale d'environnement de la JVM. Moi je veux récupérer les variables d'environnement de mon OS. Comment je peux faire?

0o.

pla78 · Answer

Salut,

   J'ai eu le m&#234;me probl&#232;me r&#233;cemment, il n'y a rien en standard!!!

   J'ai trouv&#233; du code sur Internet et je l'ai int&#232;gr&#232; en modifiant quelques trucs, et &#231; a marche sur Windows, UNIX, Linux et OS/400...

Attention je l'ai mise dans mon package util, &#224; chager &#233;ventuellement...

      Pascal,

/**
 * Copyright 2002 ROLANDS & ASSOCIATES Corporation.
 * @author David J. Ward
 */
package util;



import java.io.InputStreamReader;


/**
 * Classe permettant la r&#233;cup&#233;ration des variables d'environement plac&#233;es au
 * niveau du syt&#232;me d'exploitation.
 * @author Pascal
 * @version 7 oct. 2005
 */
public class OSEnvironment
{


  private static java.util.Properties env = null;


  /**
   * Private Constructor. OSEnvironment is not instantiable.
   */
  private OSEnvironment()
  {}


  /**
   * @return a Properties object containing the environment variables and their
   *         associated values.
   * @throws Throwable if an execption occurs.
   */
  private static java.util.Properties getEnvironment()
  {


    Process p = null;
    java.util.Properties envVars = new java.util.Properties();
    Runtime r = Runtime.getRuntime();
    String OS = System.getProperty("os.name").toLowerCase();
    boolean isEbcdic = false;
    try
    {
      // Get the Windows 95 environment variables
      if (OS.indexOf("windows 9") > -1)
      {
        p = r.exec("command.com /c set");
      }
      // Get the Windows NT environment variables
      else if (OS.indexOf("nt") > -1)
      {
        p = r.exec("cmd.exe /c set");
      }
      // Get the Windows 2000 environment variables
      else if (OS.indexOf("2000") > -1)
      {
        p = r.exec("cmd.exe /c set");
      }
      // Get the Windows XP environment variables
      else if (OS.indexOf("xp") > -1)
      {
        p = r.exec("cmd.exe /c set");
      }
      // Get the unix environment variables
      else if (OS.indexOf("linux") > -1)
      {
        p = r.exec("env");
      }
      // Pour l'AS/400 iSeries
      else if (OS.indexOf("os/400") > -1)
      {
        isEbcdic = true;
        p = r.exec("/usr/bin/env");
      }
      // Get the unix environment variables
      else if (OS.indexOf("unix") > -1)
      {
        p = r.exec("/bin/env");
      }
      // Get the unix environment variables
      else if (OS.indexOf("sunos") > -1)
      {
        p = r.exec("/bin/env");
      }
      else
      {
        System.out.println("OS not known: " + OS);
      }
      java.io.BufferedReader br;
      if (isEbcdic)
      {
        br = new java.io.BufferedReader(new InputStreamReader(p
            .getInputStream(), "Cp037"));
      }
      else
      {
        br = new java.io.BufferedReader(new InputStreamReader(p
            .getInputStream()));
      }
      String line;
      int idx;
      String key, value;
      while ((line = br.readLine()) != null)
      {
        //System.out.println("Line :" + line);
        idx = line.indexOf('=');
        // if there is no equals sign on the line skip to the net line
        // this occurs when there are newline characters in the environment
        // variable
        if (idx < 0)
          continue;
        key = line.substring(0, idx);
        value = line.substring(idx + 1);
        envVars.setProperty(key, value);
      }
    }
    catch (Exception e)
    {
      e.printStackTrace();
    }


    return envVars;
  }


  /**
   * Return a Properties object containing the environment variables.
   * @return a Properties object containing the environment variables and their
   *         associated values.
   */
  public static java.util.Properties get()
  {
    if (env == null)
      env = getEnvironment();
    return (java.util.Properties)env.clone();
  }


  /**
   * Searches for the property with the specified key in the environment. The
   * method returns null if the property is not found.
   * @param key the property key.
   * @return the value in environment with the specified key value.
   */
  public static String getProperty(String key)
  {
    if (env == null)
      env = getEnvironment();
    return env.getProperty(key);
  }


  /**
   * Searches for the property with the specified key in environment. The method
   * returns the default value argument if the property is not found.
   * @param key the hashtable key.
   * @param defaultValue a default value.
   * @return the value in this property list with the specified key value.
   */
  public static String getProperty(String key, String defaultValue)
  {
    if (env == null)
      env = getEnvironment();
    String val = env.getProperty(key);
    return (val == null) ? defaultValue : val;
  }


  /**
   * Main method to test the OSEnvironment class.
   * @param args command line arguments
   */
  public static void main(String args[])
  {
    try
    {
      java.util.Properties p = OSEnvironment.get();
      //System.out.println("Taille " + p.size());
      p.list(System.out);
      System.out.println("the current value of TEMP is : "
          + p.getProperty("TEMP"));
    }
    catch (Throwable e)
    {
      e.printStackTrace();
    }
  }


}

lara0o · Answer

Merci beaucoup pour ta reponse complete! Je teste ca cet aprem'

0o.

Recupérer des variables d'environnement

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