How to Handle the Child Window in the Selenium Web Driver TestNg by Using Frame Work?

How to Handle the Child Window in the Selenium Web Driver TestNg by Using
Frame Work?

In this code i am using the Single class and the Functional Class, Here
AllpagesLogins it is a Class Name and the this Code is Writing in the
Functional Class, Overall Scripit is running in the TestNg Class. So when
i click on the linkBtn Name as matrimonials@shaadi.com it is displaying
the Child Window in that Child Window Close Link Button Is There, So i am
write the Code for the Child Window Code also and by Direct Code, But no
one is not Working Correctly? How can i handle this Child Window?
package EmailMessage;
import java.util.Set;
import org.junit.Assert;
import org.openqa.selenium.By;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.WebElement;
import Class.AllpagesLogins;
//Declaring the Class Name
public class EmailMessage {
public void EMSG(WebDriver driver) throws Exception {
//Here AllpagesLogins is a Class Name
AllpagesLogins APL = new AllpagesLogins();
//Clicking on the Email Message Menu Button
driver.findElement(By.id(APL.EMSG_EmailMsg_MenuBtn_ID)).click();
System.out.println("Clicked on the Email Message Menu Button");
Thread.sleep(2000);
//Checking the Text for the Email Message Title
WebElement asserta=driver.findElement(By.id(APL.EMSG_EmailMsg_MainTitle_ID));
String a=asserta.getText();
try
{
Assert.assertEquals("Email Messages", a);
System.out.println("Main Title Name as Email Messages");
}
catch (Error e1)
{
System.out.println("Wrong Title");
}
//Checking the Text for the Sub Label
WebElement assertb=driver.findElement(By.id(APL.EMSG_EmailMsg_SubLbl_ID));
String b=assertb.getText();
try
{
Assert.assertEquals("Click on the Sender Email to view its details.", b);
System.out.println("Main Title Name as Sub Label");
}
catch (Error e1)
{
System.out.println("Wrong Title");
}
//Clicking on the Child Window
//getting parent Id
String Currenthandle=driver.getWindowHandle();
System.out.println("parent window id:"+Currenthandle);
//handle the child window
Set handles= driver.getWindowHandles();
handles.remove(Currenthandle);
//performing action on child window
driver.switchTo().window(handles.iterator().next());
Thread.sleep(3000);
//Clicking on the Email Message Menu Button
if(driver.findElement(By.linkText("matrimonials@shaadi.com")).isDisplayed())
{
System.out.println("Link Name is Displaying");
driver.findElement(By.linkText("matrimonials@shaadi.com")).click();
System.out.println("Clicked on the Email Id Link Button");
Thread.sleep(2000);
}
else
{
System.out.println("Link Name is Not Displaying");
}
//Handing the Child Windows
if(driver.findElement(By.name("Message Details")).isDisplayed())
{
System.out.println("Message Details Label is Displaying");
driver.findElement(By.id(APL.EMSG_ChildWindow_Close_LnkBtn_ID)).click();
System.out.println("Clicked on the Close Button in the Child Window");
Thread.sleep(2000);
}
else
{
System.out.println("Message Details Label is Not Displaying");
}
}
}