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/**
 * Understands a <code>{@link SecurityManager}</code> that does not allow an application 
 * under test to terminate the current JVM. Adapted from Abbot's own 
 * {@code SecurityManager}.
 */
public class NoExitSecurityManager extends SecurityManager {
  @Override public final void checkExit(int status) {
    if (!exitInvoked()) return;
    handleExitRequest(status);
    throw new ExitException(concat(
      "Application tried to terminate current JVM with status ", status));
  }
 
  /**
   * Implement this method to do any context-specific cleanup. This hook is provided since 
   * it may not always be possible to catch the <code>{@link ExitException}</code> 
   * explicitly (like when it's caught by someone else, or thrown from the event dispatch 
   * thread).
   * @param status the status the exit status.
   */
  protected void handleExitRequest(int status) {}
}

public class WriteToFileNoExitSecurityManager extends NoExitSecurityManager {
  // The class FileWriter only exists for the purposes of this example
  private final FileWriter fileWriter = new FileWriter("${temp}/log.txt");  
 
  @Override protected void handleExitRequest(int status) {
     fileWriter.write(concat("Exit called with status ", status));
  }
}

public class NoExitSecurityManagerTest {
  private TestNoExitSecurityManager securityManager;
 
  @Before public void setUp() {
    securityManager = new TestNoExitSecurityManager();
  }
 
  @Test public void should_prevent_application_from_exiting_and_handle_exit_request() {
    // test that an application trying to exit is effectively stopped
    ...
    // here we verify that the call to 'handleExitRequest' was made
    assertThat(securityManager.handleExitRequestCalled).isTrue();
  }
 
  private static class TestNoExitSecurityManager extends NoExitSecurityManager {
    boolean handleExitRequestCalled;   
 
    @Override protected void handleExitRequest(int status) {
      handleExitRequestCalled = true;
    }
  }
}

public interface ExitRequestHandler {
  void handleExitRequest(int status);
}

/**
 * Understands a <code>{@link SecurityManager}</code> that does not allow an application 
 * under test to terminate the current JVM. Adapted from Abbot's own 
 * {@code SecurityManager}.
 */
public final class NoExitSecurityManager extends SecurityManager {
  private final ExitRequestHandler exitRequestHandler;
 
  public NoExitSecurityManager(ExitRequestHandler exitRequestHandler) {
    this.exitRequestHandler = exitRequestHandler;
  }
 
  @Override public void checkExit(int status) {
    if (!exitInvoked()) return;
    exitRequestHandler.handleExitRequest(status);
    throw new ExitException(concat(
      "Application tried to terminate current JVM with status ", status));
  }
}

public class WriteToFileExitRequestHandler implements ExitRequestHandler {
  // The class FileWriter only exists for the purposes of this example
  private final FileWriter fileWriter = new FileWriter("${temp}/log.txt");  
 
  @Override public void handleExitRequest(int status) {
     fileWriter.write(concat("Exit called with status ", status));
  }
}

public class NoExitSecurityManagerTest {
  private ExitSecurityManager securityManager;
  private TestExitRequestHandler requestHandler;
 
  @Before public void setUp() {
    requestHandler = new ExitRequestHandler();
    securityManager = new ExitSecurityManager(requestHandler);
  }
 
  @Test public void should_prevent_application_from_exiting_and_handle_exit_request() {
    // test that an application trying to exit is effectively stopped
    ...
    // here we verify that the call to 'handleExitRequest' was made
    assertThat(requestHandler.handleExitRequestCalled).isTrue();
  }
 
  private static class TestExitRequestHandler implements ExitRequestHandler {
    boolean handleExitRequestCalled;   
 
    @Override public void handleExitRequest(int status) {
      handleExitRequestCalled = true;
    }
  }
}