Java如何获取系统属性信息？

package org.nhooo.example.management;

import java.lang.management.ManagementFactory;
import java.lang.management.RuntimeMXBean;
import java.util.Map;
import java.util.Set;

public class GetSystemProperties {
    public static void main(String[] args) {
        RuntimeMXBean bean = ManagementFactory.getRuntimeMXBean();

        // 返回所有系统的名称和值的映射
        //属性。此方法调用System.getProperties()
        //获取所有系统属性。其属性
        // 名称或值不是字符串将被省略。
        Map<String, String> systemProperties = bean.getSystemProperties();
        Set<String> keys = systemProperties.keySet();
        for (String key : keys) {
            String value = systemProperties.get(key);
            System.out.printf("Property[%s] = %s.%n", key, value);
        }
    }
}

上面的代码片段捕获的一些属性信息是：

Property[java.vm.vendor] = Oracle Corporation.
Property[sun.arch.data.model] = 64.
Property[java.vendor.url] = http://java.oracle.com/.
Property[user.timezone] = .
Property[user.country.format] = ID.
Property[os.name] = Mac OS X.
Property[java.vm.specification.version] = 1.8.
Property[user.country] = US.
Property[sun.java.launcher] = SUN_STANDARD.
Property[sun.boot.library.path] = /Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/jre/lib.
Property[sun.java.command] = org.nhooo.example.management.GetSystemProperties.
Property[http.nonProxyHosts] = local|*.local|169.254/16|*.169.254/16.
Property[sun.cpu.endian] = little.
Property[user.home] = /Users/wsaryada.
Property[user.language] = en.
Property[java.specification.vendor] = Oracle Corporation.
Property[java.home] = /Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/jre.
Property[file.separator] = /.
Property[line.separator] = 
.
Property[java.vm.specification.vendor] = Oracle Corporation.
Property[java.specification.name] = Java Platform API Specification.
Property[java.awt.graphicsenv] = sun.awt.CGraphicsEnvironment.