java script with post method of httpclient

I am trying to login to yahoo.de with httpclient in java (I am crawling the site). To submit a form having username and password, I use 开发者_运维知识库Postmethod. I found that I have to pass some hidden values (which are generated dynamically) along with username and password in post method. Does anybody know how do I do this ? How do I handle javascript with httpclient ? Any help would be appreciated !

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I doubt HTTPClient would support java-script, you might have to find if Yahoo supports non-javascript login process in the page and grasp those fields to login through.

Otherwise use, yahoo's open-id API to authenticate the user. More information here: http://developer.yahoo.com/openid/