Retrieve KEYWORDS from META tag in a HTML WebPage using JAVA
I want to retrieve all the content words from a HTML WebPage and all the keywords contained in the META TAG of the same HTML webpage using Java.
For example, consider this html source code:<html>
<head>
<meta name = "keywords" content = "deception, intricacy, treachery">
</head>
<body>
My very short html document.
<br>
It has just 2 'lines'.
</body>
</html>
The CONTENT WORDS here are: my, very, short, html, document, it, has, just, lines
Note: The punctuation and the number '2' are ruled out.
The KEYWORDS here are: deception, intricacy, treachery
I have created a class for this purpose called WebDoc, this is as far as I have been able to get.
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.URL;
import java.util.Set;
import java.util.TreeSet;
public class WebDoc {
protected URL _url;
protected Set<String> _contentWords;
protected Set<String> _keyWords
public WebDoc(URL paramURL) {
_url = paramURL;
}
public Set<String> getContents() throws IOException {
//URL url = new URL(url);
Set<String> contentWords = new TreeSet<String>();
BufferedReader in = new BufferedReader(new InputStreamReader(_url.openStream()));
String inputLine;
while ((inputLine = in.readLine()) != null) {
// Process each line.
contentWords.add(RemoveTag(开发者_开发问答inputLine));
//System.out.println(RemoveTag(inputLine));
}
in.close();
System.out.println(contentWords);
_contentWords = contentWords;
return contentWords;
}
public String RemoveTag(String html) {
html = html.replaceAll("\\<.*?>","");
html = html.replaceAll("&","");
return html;
}
public Set<String> getKeywords() {
//NO IDEA !
return null;
}
public URL getURL() {
return _url;
}
@Override
public String toString() {
return null;
}
}
So, after the answer from RedSoxFan about the meta-keywords, you only need to split your content lines. You can use a similar method there:
Instead of
contentWords.add(RemoveTag(inputLine));
use
contentWords.addAll(Arrays.asList(RemoveTag(inputLine).split("[^\\p{L}]+")));
.split(...)splits your line at all non-letters (I hope this works, please try and report), giving back an array of substrings, which each should contain only of letters, and some empty strings between.Arrays.asList(...)wraps this array in a list.addAll(...)adds all the elements of this array to the set, but not duplicates).
At the end you should delete the empty string "" from your contentWords-Set.
Process each line and use
public Set<String> getKeywords(String str) {
Set<String> s = new HashSet<String>();
str = str.trim();
if (str.toLowerCase().startsWith("<meta ")) {
if (str.toLowerCase().matches("<meta name\\s?=\\s?\"keywords\"\\scontent\\s?=\\s?\".*\"/?>")) {
// Returns only whats in the content attribute (case-insensitive)
str = str.replaceAll("(?i)<meta name\\s?=\\s?\"keywords\"\\scontent\\s?=\\s?\"(.*)\"/?>","$1");
for (String st:str.split(",")) s.add(st.trim());
return s;
}
}
return null;
}
If you need an explanation, let me know.
加载中,请稍侯......
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