securitytestwindow.java

21天学通java的示例程序源代码

/*
 * SecurityTestWindow.java
 */

package com.wrox.security;

import java.awt.*;
import java.io.File;
import java.net.URLConnection;

/**
 * This class implements a window (java.awt.Frame) with a single text
 * field. The text field displays the results of the various security
 * tests.
 */
class SecurityTestWindow extends Frame {

  private TextArea textArea;

  /**
   * Constructs a security test window with the given title.
   * @param title The window title.
   */
  public SecurityTestWindow(String title) {
    super(title);

    textArea = new TextArea();
    textArea.setEditable(false);
    add(textArea);

    pack();
    show();
  }

  /**
   * Runs the security tests and displays the results.
   */
  public void showTestResults() {
    println("Running tests...");
    try {
      fileTest("/");
    } catch (Exception e) {
      println(e);
    } 
    try {
      socketTest("http://www.wrox.com");
    } catch (Exception e) {
      println(e);
    } 
    try {
      systemTest("user.home");
    } catch (Exception e) {
      println(e);
    } 
    println("Done.");
  } 

  /**
   * Test file (directory) access permission by taking a directory and
   * displaying the first filename from it.
   * @param path The directory to list
   */
  private void fileTest(String path) {
    String[] files = new java.io.File(path).list();
    if (files.length > 0) {
      println("First file in " + path + " is " + files[0]);
    } 
  } 

  /**
   * Test network access permission by downloading a HTML page and
   * displaying its length.
   * @param url The URL of the page to download
   */
  private void socketTest(String url) throws java.io.IOException {
    URLConnection connection = new java.net.URL(url).openConnection();
    connection.connect();
    println(url + " is " + connection.getContentLength() + " bytes");
    connection.getInputStream().close();
  } 

  /**
   * Test access to privileged system properties
   * @param property The name of the property to retrieve
   */
  private void systemTest(String property) {
    println(property + " has value " + System.getProperty(property));
  } 

  /**
   * Print a line of text to the text area
   * @param toPrint The object or text to print
   */
  private void println(Object toPrint) {
    textArea.append(toPrint + "\n");
  } 
}