getprops.java

一个控制用户访问权限的小程序

package javasecurity;
import java.lang.*;
import java.security.*;
class GetProps
{
	public static void main(String[] args)
	{
		String s;
		try
		{
			System.out.println("About to get os.name property value");
			//获得系统名称
			s = System.getProperty("os.name", "not specified");
			System.out.println(
"The name of your operating system is: "+s);
			System.out.println(
"About to get java.version property value");
			//获得JVM版本
			s = System.getProperty("java.version", "not specified");
			System.out.println(
				"  The version of the JVM you are running is: " + s);
			System.out.println("About to get user.home property value");
			//获得用户缺省路径
			s = System.getProperty("user.home", "not specified");
			System.out.println("Your user home directory is: " + s);
			System.out.println("About to get java.home property value");
			//获得JVM缺省路径
			s = System.getProperty("java.home", "not specified");
			System.out.println("Your JRE installation directory is: "+s);
		}
		catch (Exception e)
		{
			System.err.println("Caught exception " + e.toString());
		}
	}
}