2019独角兽企业重金招聘Python工程师标准>>> 
// File: io/properties/SysPropList.java
// Description: Shows system properties. This must be an application.
// An applet can't get this information.
// Author: Fred Swartz
// Date: 2 Feb 2005import java.awt.BorderLayout;
import java.util.Iterator;
import java.util.Properties;
import java.util.TreeSet;import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;/** Generic main program. */
public class SysPropList {public static void main(String[] args) {JFrame window = new JFrame("System Properties");window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);window.setContentPane(new SysPropListGUI ());window.pack();window.setVisible(true);}
}/** Panel to display the (limited) GUI intereface. */
class SysPropListGUI extends JPanel {JTextArea m_propertiesTA = new JTextArea(20, 40);/** Constructor sets layout, adds component(s), sets values*/public SysPropListGUI () {this.setLayout(new BorderLayout());this.add(new JScrollPane(m_propertiesTA), BorderLayout.CENTER);//... Add property list data to text area.Properties pr = System.getProperties();TreeSet propKeys = new TreeSet(pr.keySet()); // TreeSet sorts keysfor (Iterator it = propKeys.iterator(); it.hasNext(); ) {String key = (String)it.next();m_propertiesTA.append("" + key + "=" + pr.get(key) + "\n");}}
}
