identity.java.svn-base

一些公用的Java函数

/*
 * Identity.java
 * 
 * Created on 2007-10-30, 10:48:13
 * 
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */

package com.s7turn.jaas;

import java.security.Principal;
import javax.el.ELContext;
import javax.faces.context.ExternalContext;
import javax.faces.context.FacesContext;
import javax.servlet.ServletRequest;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 *
 * @author Long
 */
public abstract class Identity 
{
    ///facecontext
    public static Identity getCurrentIdentity()
    {
        FacesContext fctx = FacesContext.getCurrentInstance();
        if( fctx != null )
        {
            ELContext elCtx = fctx.getELContext();
            if( elCtx != null )
            {
                return (Identity) elCtx.getELResolver().getValue( elCtx, null, "identity" );
            }
        }
        return null;
    }
    
    public static Identity getCurrentIdentity( ServletRequest request )
    {
        Identity identity = null;
        if( request instanceof HttpServletRequest )
        {
            HttpServletRequest hsr = (HttpServletRequest) request;
            identity = (Identity) hsr.getSession().getAttribute("identity");
            if( identity == null )
            {
                ////load identity from cookie. we will get the token from cookie and parse it as well.
                Cookie[] cookies = hsr.getCookies();
                String token = null;
                if( cookies != null && cookies.length > 0 )
                {
                    for( Cookie ck : cookies )
                    {
                        if( "s7turn_token".equals( ck.getName() ) )
                        {
                            token = ck.getValue();
                            break;
                        }
                    }
                }
                 
                if( token == null || token.trim().length() == 0 )
                {
                    ///So we will check the url from the action, that will contain the token.
                    token = hsr.getParameter("s7turn_token");
                }
                
                if( token != null && token.trim().length() > 0 )
                {
                    SecurityProvider provider = SecurityHelper.getInstance().getSecurityProvider();
                    identity = provider.createIdentity(); 
                    if( identity.parseLogin(token) )
                    {
                        ///identity.commit(age);
                        ////Add the identity to session
                        hsr.getSession().setAttribute("identity", identity );
                    }
                    ///then parse the token and login it.
                }
            }
        }

        return identity;
    }
    
    public boolean isUserInRole( String regex )
    {
        return SecurityHelper.getInstance().getSecurityProvider().isUserInRole(this, regex);
    }
    
    ////this method parse the token as perform login.
    protected boolean parseLogin( String loginToken )
    {
        return false;
    }
    
    public boolean isLoggedIn()
    {
        return getMember() != null;
    }
    
    public String getUserName()
    {
        return isLoggedIn() ? getMember().getName() : "guest";
    }
    
    public abstract Principal getMember();
    
    /**
     * this method check the login user has the op permission of the resource
     * 
     * @param res
     * @param op
     * @return
     */
    public abstract boolean hasPermission( String res, String op );
    
    ////This method is for JSF method, that will be called after the chain ended.
    public String login()
    {
        ///So, we can get the JSF Context.
        /// and call commit method save some information into cookie.
        commit( 24 * 60 * 60 * 1000 );
        return "loggedIn";
    }
    
    public String logout()
    {
        commit( -1 );
        return "loggedOut";
    }
    
    ////below token method will be used to save the security identity
    ////between system and client.
    public String getTokenName()
    {
        return "s7turn_token"; ///
    }
    
    public String getToken()
    {
        ////the token will combie the user's identity information and 
        return "";
    }
    
    ///commit this login section.
    protected void commit( int age )
    {
        FacesContext fctx = FacesContext.getCurrentInstance();
        if( fctx != null )
        {
            ExternalContext ectx = fctx.getExternalContext();
            if( ectx != null )
            {
                Object rsp =  ectx.getResponse();
                if( rsp instanceof HttpServletResponse )
                {
                    HttpServletResponse response = (HttpServletResponse) rsp;
                    Cookie cookie = new Cookie( getTokenName(), this.getToken() );
                    //cookie.setDomain( "" );
                    //URL url = new URL( buf.toString() );
                    //cookie.setPath( ectx.getRequestContextPath() );
                    cookie.setSecure( ((HttpServletRequest) ectx.getRequest()).isSecure() );
                    cookie.setMaxAge( age );
                    response.addCookie( cookie );
                }
            }
        }
    }
    
    
}