使用Jsoup如何知道HTML页面中是否存在标签名称

Question

I am trying to get some values from a web site. and want to use a method to check if one rule is available get the value from that rule or else the second one. for example

Document d=Jsoup.connect("some site name")
.userAgent("Mozilla/5.0 (X11; CrOS i686 3912.101.0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/27.0.1453.116 Safari/537.36").timeout(100000).get();

This is sample i have done but not working

if(d.getAllElements().hasAttr("bld lrg red")) { 
    System.out.println("insidee IF"); 
    Elements e = d.select("span[class=bld lrg red]"); 
    String TEXT=e.text(); 
    System.out.println(TEXT);
} else {
    System.out.println("inside ELSE ");
    Elements e=d.select("td[class~=(?i)(toeNewPrice|toeUsedPrice)]");
    String TEXT=e.text();
    System.out.println(TEXT);
}

if bld lrg red is available then take from if and if not available take value from else

Answer 1

If you are checking for a span tag with all those classes the try like

if(doc.select("span.bld.lrg.red").size() > 0) { 
    System.out.println("insidee IF"); 
    Elements e = d.select("span[class=bld lrg red]"); 
    String TEXT=e.text(); 
    System.out.println(TEXT);
} else {
    System.out.println("inside ELSE ");
    Elements e=d.select("td[class~=(?i)(toeNewPrice|toeUsedPrice)]");
    String TEXT=e.text();
    System.out.println(TEXT);
}