com.thoughtworks.selenium.Wait Maven / Gradle / Ivy

/*
Copyright 2006-2012 Selenium committers
Copyright 2006-2012 Software Freedom Conservancy

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

     http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/


package com.thoughtworks.selenium;

/**
 * A utility class, designed to help the user automatically wait until a condition turns true.
 * 
 * Use it like this:
 * 
 * 
 * new Wait("Couldn't find close button!") {
 
 *     boolean until() {

 *         return selenium.isElementPresent("button_Close");

 *     }

 * };
 * 
 * 
 * 
 * @author Dan Fabulich
 * 
 */
public abstract class Wait {
  public Wait() {
  }

  public Wait(String messageToShowIfTimeout) {
    wait(messageToShowIfTimeout, DEFAULT_TIMEOUT, DEFAULT_INTERVAL);
  }

  /** Returns true when it's time to stop waiting */
  public abstract boolean until();

  /** The amount of time to wait before giving up; the default is 30 seconds */
  public static final long DEFAULT_TIMEOUT = 30000l;

  /** The interval to pause between checking; the default is 500 milliseconds */
  public static final long DEFAULT_INTERVAL = 500l;

  /**
   * Wait until the "until" condition returns true or time runs out.
   * 
   * @param message the failure message
   * @param timeoutInMilliseconds the amount of time to wait before giving up
   * @throws WaitTimedOutException if "until" doesn't return true until the timeout
   * @see #until()
   */
  public void wait(String message) {
    wait(message, DEFAULT_TIMEOUT, DEFAULT_INTERVAL);
  }

  /**
   * Wait until the "until" condition returns true or time runs out.
   * 
   * @param message the failure message
   * @param timeoutInMilliseconds the amount of time to wait before giving up
   * @throws WaitTimedOutException if "until" doesn't return true until the timeout
   * @see #until()
   */
  public void wait(String message, long timeoutInMilliseconds) {
    wait(message, timeoutInMilliseconds, DEFAULT_INTERVAL);
  }

  /**
   * Wait until the "until" condition returns true or time runs out.
   * 
   * @param message the failure message
   * @param timeoutInMilliseconds the amount of time to wait before giving up
   * @param intervalInMilliseconds the interval to pause between checking "until"
   * @throws WaitTimedOutException if "until" doesn't return true until the timeout
   * @see #until()
   */
  public void wait(String message, long timeoutInMilliseconds, long intervalInMilliseconds) {
    long start = System.currentTimeMillis();
    long end = start + timeoutInMilliseconds;
    while (System.currentTimeMillis() < end) {
      if (until()) return;
      try {
        Thread.sleep(intervalInMilliseconds);
      } catch (InterruptedException e) {
        throw new RuntimeException(e);
      }
    }
    throw new WaitTimedOutException(message);
  }

  public class WaitTimedOutException extends RuntimeException {

    private static final long serialVersionUID = 1L;

    public WaitTimedOutException() {
      super();
    }

    public WaitTimedOutException(String message, Throwable cause) {
      super(message, cause);
    }

    public WaitTimedOutException(String message) {
      super(message);
    }

    public WaitTimedOutException(Throwable cause) {
      super(cause);
    }

  }
}