You can do this:
//first get all the <a> elements
List<WebElement> linkList=driver.findElements(By.tagName("a"));
//now traverse over the list and check
for(int i=0 ; i<linkList.size() ; i++)
{
if(linkList.get(i).getAttribute("href").contains("long"))
{
linkList.get(i).click();
break;
}
}
in this what we r doing is first we are finding all the <a> tags and storing them in a list.After that we are iterating the list one by one to find <a> tag whose href attribute contains long string. And then we click on that particular <a> tag and comes out of the loop.