我运行appium java脚本成功.但问题是，我的应用程序开始与登录页面.登录后，我可以自动化一些测试用例.但我想再次从登录页面通过脚本来运行下一个测试用例..我如何关闭应用程序，也从后台模式，并重新打开applicciation没有重新安装应用程序一次？因为测试用例不应该相互依赖，

public class AppTest {
    
    private static RemoteWebDriver driver;
      
    @BeforeClass
    public static void initSimulator() throws MalformedURLException
    {
            DesiredCapabilities capabilities = new DesiredCapabilities();

            capabilities.setCapability("platformName", "Android");            
            capabilities.setCapability("platformVersion", "5.0.1");           
            capabilities.setCapability("deviceName", "emulator-5554");                
            capabilities.setCapability("app", "D:\\adt-bundle-windows-x86_64-20140702\\sdk\\platform-tools\\Yr.apk");    
            capabilities.setCapability("app-package", "com.you.android");                   
            capabilities.setCapability("app-activity", "com.yr.sts.SplashActivity");                  
            capabilities.setCapability("app_wait_activity",".MainActivity");
            
            driver = new RemoteWebDriver(new URL("http://127.0.0.1:4723/wd/hub"),
                capabilities);
          
            System.out.println("App Launched");
    }
    @AfterClass
    public static void quitDriver() 
    {
       driver.quit();
       System.out.println("Driver has been Quit");
    }

    @Test
    public void sign_in_Click() throws InterruptedException 
    {
        WebElement sign_button = driver.findElement(By.name("Sign-in"));
        sign_button.click();
        WebElement usr = driver.findElement(By.id("com.you.android:id/et_login_email_or_mobile"));
        usr.sendKeys("[email protected]");
        Thread.sleep(2000);
        WebElement passwrd = driver.findElement(By.id("com.you.android:id/et_login_pwd"));
        passwrd.sendKeys("123456789");
        Thread.sleep(2000);
        driver.findElementByName("Sign in").click();
        Thread.sleep(5000);
        assertTrue( true );
    }
    @Test
    public void second_sign_in_Click() throws InterruptedException 
    {    
        //HERE I WANT TO REOPEN THE APPLICATION WITH SIGN IN  AFTER CLOSING APP.BECAUSE IN 1st TESTCASE , I HAVE SIGNED IN.this is a 2nd test case    
    }
}