environment.java

SRI international 发布的OAA框架软件

/**
 * The contents of this file are subject to the OAA  Community Research
 * License Version 2.0 (the "License"); you may not use this file except
 * in compliance with the License. You may obtain a copy of the License
 * at http://www.ai.sri.com/~oaa/.  Software distributed under the License
 * is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, either
 * express or implied. See the License for the specific language governing
 * rights and limitations under the License.  Portions of the software are
 * Copyright (c) SRI International, 1999-2003.  All rights reserved.
 * "OAA" is a registered trademark, and "Open Agent Architecture" is a
 * trademark, of SRI International, a California nonprofit public benefit
 * corporation.
*/

package com.sri.oaa2.agt.startit;

import java.util.*;
import java.io.*;

public class Environment {

  // HostTypes
  public static final int UNKNOWN          = 1301;
  public static final int UNIX             = 1302;
  public static final int WINDOWS_9x       = 1303;
  public static final int WINDOWS_ME       = 1304;
  public static final int WINDOWS_NT       = 1305;
  public static final int MAC_OS_X          = 1306;

  static private Properties env = new Properties();
  static private int hostType = UNKNOWN;
  static private boolean envCached = false;
  static private boolean hostCached = false;

  // see: http://www.tolstoy.com/samizdat/sysprops.html
  //      for some dude's list of possible os.name values
  public static int getHostType() {
    if (hostCached) return hostType;

    String OS = System.getProperty("os.name").toLowerCase();
    String MAC_ID = "";
    if (OS.matches("windows me")) {
      hostType = WINDOWS_ME;
    }
    else if (OS.matches("windows 9.*")) {
      hostType = WINDOWS_9x;
    }
    else if (OS.matches("mac os x")) {
      hostType = MAC_OS_X;
    }
    else if (OS.matches("windows ?(nt|2000|xp|2003).*")) {
      hostType = WINDOWS_NT;
    }
    else if (OS.matches("sunos|solaris|(.*[iu]x)")) { // linux, aix, irix ... 
      hostType = UNIX;
    }
    else {  
      hostType = UNKNOWN;
    }
    hostCached = true;
    return hostType;
  }

  public static boolean isOSX() {
    return isOSX(getHostType());
  }

  public static boolean isOSX(int type) {
    return (type == MAC_OS_X);   
  }
  public static boolean isUnix() {
    return isUnix(getHostType());
  }

  public static boolean isUnix(int type) {
    return (type == UNIX);
  }

  public static boolean isWindows() {
    return isWindows(getHostType());
  }

  public static boolean isWindows(int type) {
    return (type == WINDOWS_ME || type == WINDOWS_9x || type == WINDOWS_NT);
  }

  public static String getUserName() {
    if (isUnix() || isOSX()) {
      return get("USER");
    }
    else {
      return get("USERNAME");
    }
  }

  public static String get(String key) {
    return (String) get().get(key);
  }

  public static Properties get() {
    if (envCached) return env;

    //(see http://www.rgagnon.com/javadetails/java-0150.html)
    Process p = null;
    Runtime r = Runtime.getRuntime();
    String line;

    try {
      switch (getHostType()) {
      case WINDOWS_ME:
	// Don't try to support Windows Me!  It crashes the whole machine HARD!
	break;
      case WINDOWS_9x:
	p = r.exec( "command.com /c set" );
	break;
      case WINDOWS_NT:
	p = r.exec( "cmd.exe /c set" );
	break;
      case UNIX:
	p = r.exec( "env" );
	break;
      case MAC_OS_X:
	p = r.exec( "env" );
	break;
	
      default:
	// leave p NULL, to get caught in catch clause below
	break;
      }
      BufferedReader br = new BufferedReader(new InputStreamReader(p.getInputStream()));
      while((line = br.readLine()) != null) {
	String[] keyval = line.split("=", 2);
	if (keyval.length >= 2) {
	  env.put(keyval[0], keyval[1]);
	}
      }
    }
    catch (IOException e) {
      System.err.println("WARNING: error getting environment variables into java");
      System.err.println("         OS = " + System.getProperty("os.name"));
      System.err.println("              " + e);
    }
    catch (NullPointerException e) {
      System.err.println("WARNING: environment variables not supported for OS: " + System.getProperty("os.name"));
    }

    envCached = true;
    return env;
  }

  public static void merge(Properties props, boolean override) {
    get(); // ensure we cache system environment
    for (Iterator i = props.keySet().iterator(); i.hasNext(); ) {
      String key = (String) i.next();
      if (override || !env.containsKey(key)) {
	env.put(key, props.get(key));
      }
    }
  }
  
}