2013 Multi-University Training Contest 1――I-number

在Java中，系统属性是通过System.getProperty(String key)来获取的，也可以通过System.setProperty(String key, Object value)来设置。
对于获取系统属性的代码是非常简单的，主要是把所有系统默认存储的属性打印出来，以后就可以直接查了，不用每次都去Google。
 
代码：
       Properties props = System.getProperties();
       for(Entry<Object, Object> entry : props.entrySet()) {
           Object key = entry.getKey();
           Object value = entry.getValue();
           System.out.println(key + " - " + value);
       }
运行结果：
java.runtime.name - Java(TM) SE Runtime Environment
sun.boot.library.path - C:\Program Files\Java\jre6\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 -
java.vm.specification.name - Java Virtual Machine Specification
user.dir -
java.runtime.version - 1.6.0_21-b07
java.awt.graphicsenv - sun.awt.Win32GraphicsEnvironment
java.endorsed.dirs - C:\Program Files\Java\jre6\lib\endorsed
os.arch - x86
java.io.tmpdir - C:\Users\Levin\AppData\Local\Temp\
line.separator -
 
java.vm.specification.vendor - Sun Microsystems Inc.
user.variant -
os.name - Windows 7
sun.jnu.encoding - GBK
java.library.path - C:\Program Files\Java\jre6\bin;.;C:\Windows\Sun\Java\bin;C:\Windows\system32;C:\Windows;C:/Program Files/Java/jre6/bin/client;C:/Program Files/Java/jre6/bin;C:/Program Files/Java/jre6/lib/i386;C:\Windows\system32;C:\Windows;C:\Windows\System32\Wbem;C:\Windows\System32\WindowsPowerShell\v1.0\;C:\Program Files\ATI Technologies\ATI.ACE\Core-Static;C:\Program Files\Java\jdk1.6.0_21\bin;C:\Program Files\Common Files\Thunder Network\KanKan\Codecs;E:\Program Files\Ant\apache-ant-1.8.1\bin;C:\Program Files\Rational\common
java.specification.name - Java Platform API Specification
java.class.version - 50.0
sun.management.compiler - HotSpot Client Compiler
os.version - 6.1
user.home - C:\Users\Levin
user.timezone -
java.awt.printerjob - sun.awt.windows.WPrinterJob
file.encoding - GBK
java.specification.version - 1.6
java.class.path - E:\CodeRepository\Java\TomcatReading\MyClassLoader\bin;E:\CodeRepository\Java\TomcatReading\DomainInterfaces\bin;E:\CodeRepository\Java\ExtClassPath;E:\CodeRepository\Java\TomcatReading\DomainLib\bin
user.name - Levin
java.vm.specification.version - 1.0
java.home - C:\Program Files\Java\jre6
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, sharing
java.version - 1.6.0_21
java.ext.dirs - C:\Program Files\Java\jre6\lib\ext;C:\Windows\Sun\Java\lib\ext
sun.boot.class.path - C:\Program Files\Java\jre6\lib\resources.jar;C:\Program Files\Java\jre6\lib\rt.jar;C:\Program Files\Java\jre6\lib\sunrsasign.jar;C:\Program Files\Java\jre6\lib\jsse.jar;C:\Program Files\Java\jre6\lib\jce.jar;C:\Program Files\Java\jre6\lib\charsets.jar;C:\Program Files\Java\jre6\classes
java.vendor - Sun Microsystems Inc.
file.separator - \
java.vendor.url.bug - http://java.sun.com/cgi-bin/bugreport.cgi sun.io.unicode.encoding - UnicodeLittle
sun.cpu.endian - little
sun.desktop - windows
sun.cpu.isalist - pentium_pro+mmx pentium_pro pentium+mmx pentium i486 i386 i86