Java获取特殊目录或特殊值

public static void main(String[] args) {
		
		Properties properties = System.getProperties()  ;
		
		for(Map.Entry<?, ?> entry : properties.entrySet()){
			System.out.println( entry.getKey() 
					 + "-->" + entry.getValue() ); 
		}
		System.out.println( System.getProperty("##########################") ); 
		Map<String , String> map = System.getenv() ; 
		for(Map.Entry<?, ?> entry : map.entrySet()){
			System.out.println( entry.getKey() 
					 + "-->" + entry.getValue() ) ;  
		} 
	}

系统输出这样的结果：
java.runtime.name-->Java(TM) SE Runtime Environment

sun.boot.library.path-->E:\soft\JAVA\jdk1.6.0_21\jre\bin

java.vm.version-->17.0-b17

java.vm.vendor-->Sun Microsystems Inc.

java.vendor.url-->http://java.sun.com/

path.separator-->;

java.vm.name-->Java HotSpot(TM) Client VM

file.encoding.pkg-->sun.io

sun.java.launcher-->SUN_STANDARD

user.country-->CN

sun.os.patch.level-->Service Pack 3

java.vm.specification.name-->Java Virtual Machine Specification

user.dir-->F:\httpclient

java.runtime.version-->1.6.0_21-b07

java.awt.graphicsenv-->sun.awt.Win32GraphicsEnvironment

java.endorsed.dirs-->E:\soft\JAVA\jdk1.6.0_21\jre\lib\endorsed

os.arch-->x86

java.io.tmpdir-->C:\DOCUME~1\ADMINI~1\LOCALS~1\Temp\

line.separator-->

java.vm.specification.vendor-->Sun Microsystems Inc.

user.variant-->

os.name-->Windows XP

sun.jnu.encoding-->GBK

java.library.path-->E:\soft\JAVA\jdk1.6.0_21\bin;.;C:\WINDOWS\Sun\Java\bin;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\Wbem;E:\soft\JAVA\jdk1.6.0_21\bin;E:\soft\apache-maven-3.0.4\bin\;

java.specification.name-->Java Platform API Specification

java.class.version-->50.0

sun.management.compiler-->HotSpot Client Compiler

os.version-->5.1

user.home-->C:\Documents and Settings\Administrator

user.timezone-->

java.awt.printerjob-->sun.awt.windows.WPrinterJob

file.encoding-->GBK

java.specification.version-->1.6

java.class.path-->F:\httpclient\WebRoot\WEB-INF\classes

user.name-->Administrator

java.vm.specification.version-->1.0

java.home-->E:\soft\JAVA\jdk1.6.0_21\jre

sun.arch.data.model-->32

user.language-->zh

java.specification.vendor-->Sun Microsystems Inc.

awt.toolkit-->sun.awt.windows.WToolkit

java.vm.info-->mixed mode

java.version-->1.6.0_21

java.ext.dirs-->E:\soft\JAVA\jdk1.6.0_21\jre\lib\ext;C:\WINDOWS\Sun\Java\lib\ext

sun.boot.class.path-->E:\soft\JAVA\jdk1.6.0_21\jre\lib\resources.jar;E:\soft\JAVA\jdk1.6.0_21\jre\lib\rt.jar;E:\soft\JAVA\jdk1.6.0_21\jre\lib\sunrsasign.jar;E:\soft\JAVA\jdk1.6.0_21\jre\lib\jsse.jar;E:\soft\JAVA\jdk1.6.0_21\jre\lib\jce.jar;E:\soft\JAVA\jdk1.6.0_21\jre\lib\charsets.jar;E:\soft\JAVA\jdk1.6.0_21\jre\classes;E:\soft\JAVA\MyEclipse\myeclipse\eclipse\plugins\com.genuitec.eclipse.j2eedt.core_6.5.0.zmyeclipse650200806\data\libraryset\1.4\activation.jar;E:\soft\JAVA\MyEclipse\myeclipse\eclipse\plugins\com.genuitec.eclipse.j2eedt.core_6.5.0.zmyeclipse650200806\data\libraryset\1.4\javax.servlet.jar;E:\soft\JAVA\MyEclipse\myeclipse\eclipse\plugins\com.genuitec.eclipse.j2eedt.core_6.5.0.zmyeclipse650200806\data\libraryset\1.4\javax.servlet.jsp.jar;E:\soft\JAVA\MyEclipse\myeclipse\eclipse\plugins\com.genuitec.eclipse.j2eedt.core_6.5.0.zmyeclipse650200806\data\libraryset\1.4\jboss-j2ee.jar;E:\soft\JAVA\MyEclipse\myeclipse\eclipse\plugins\com.genuitec.eclipse.j2eedt.core_6.5.0.zmyeclipse650200806\data\libraryset\1.4\jboss-jaxrpc.jar;E:\soft\JAVA\MyEclipse\myeclipse\eclipse\plugins\com.genuitec.eclipse.j2eedt.core_6.5.0.zmyeclipse650200806\data\libraryset\1.4\jboss-jsr77.jar;E:\soft\JAVA\MyEclipse\myeclipse\eclipse\plugins\com.genuitec.eclipse.j2eedt.core_6.5.0.zmyeclipse650200806\data\libraryset\1.4\jboss-saaj.jar;E:\soft\JAVA\MyEclipse\myeclipse\eclipse\plugins\com.genuitec.eclipse.j2eedt.core_6.5.0.zmyeclipse650200806\data\libraryset\1.4\mail.jar;E:\soft\JAVA\MyEclipse\myeclipse\eclipse\plugins\com.genuitec.eclipse.j2eedt.core_6.5.0.zmyeclipse650200806\data\libraryset\1.4\namespace.jar;E:\soft\JAVA\MyEclipse\myeclipse\eclipse\plugins\com.genuitec.eclipse.j2eedt.core_6.5.0.zmyeclipse650200806\data\libraryset\1.4\xml-apis.jar