metadataservlet.java

Some common function write by java

/*
 * MetadataServlet.java
 * 
 * Created on 2007-11-4, 21:18:33
 * 
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */

package com.s7turn.jaas.webapps;

import com.s7turn.sdk.content.Metadata;
import com.s7turn.sdk.content.MetadataFactory;
import com.s7turn.sdk.content.MetadataProvider;
import com.s7turn.sdk.utils.ImageUtils;
import java.io.*;
import java.net.*;

import javax.servlet.*;
import javax.servlet.http.*;

/**
 *
 * @author Long
 */
public class MetadataServlet extends HttpServlet {
   
    /** 
    * Processes requests for both HTTP <code>GET</code> and <code>POST</code> methods.
    * @param request servlet request
    * @param response servlet response
    */
    protected void processRequest(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException 
    {
        String mid = request.getParameter("mid");
        String md5 = request.getParameter("md5");
        String thumb = request.getParameter( "thumb" );
        String metadataFactory = this.getInitParameter( "com.s7turn.metadataFactory" );
        int bufferSize = 0;
        String strBffSz = this.getInitParameter("com.s7turn.bufferSize");
        if( strBffSz != null && strBffSz.trim().length() > 0 )
        {
            bufferSize = Integer.parseInt( strBffSz );
        }
        else
        {
            bufferSize = 4096;
        }
        
        MetadataFactory factory = MetadataFactory.createInstance( metadataFactory );
        
        MetadataProvider provider = factory.createProvider();
        
        Metadata meta = null;
        
        if( mid == null || mid.trim().length() == 0 )
        {
            meta = provider.getMetadata(md5);
        }
        else
        {
            meta = provider.getMetadata( Long.parseLong ( mid ) );
        }
        
        
        if( meta == null )
        {
            ////generate 404 error.
            ServletException se = new ServletException();
            throw new ServletException();
        }
        
        response.reset();
        
        response.setContentType( meta.getMetaType() + "; charset=utf-8" );
        
        ServletOutputStream output = response.getOutputStream();
        
        byte[] buffer = meta.getContent();
        ///InputStream input = meta.getContent();
        try
        {
                ////Check the thumb option.
                if( isImage( meta ) && (thumb != null && thumb.trim().length() > 0) )
                {
                    thumb = thumb.trim().toLowerCase();
                    String[] splitedDimon = thumb.split("x");
                    int width = 320;
                    int height = 320;
                    try{ width = Integer.parseInt( splitedDimon[0] ); } catch(Exception ex){}
                    try{ height = Integer.parseInt( splitedDimon[1] ); } catch(Exception ex){}
                    ImageUtils.resizeImage(buffer, width, height, output);
                }
                else
                {
                    output.write( buffer, 0, buffer.length );
                }
                
        }catch(Exception ex){
            throw new ServletException( ex.getMessage(), ex );
        }
        finally
        {
            output.flush();
        }
    }
    
    public boolean isImage( Metadata meta )
    {
        if( meta == null )
            return false;
        return  meta.getMetaType().startsWith("image/");
    }

    // <editor-fold defaultstate="collapsed" desc="HttpServlet methods. Click on the + sign on the left to edit the code.">
    /** 
    * Handles the HTTP <code>GET</code> method.
    * @param request servlet request
    * @param response servlet response
    */
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
        processRequest(request, response);
    } 

    /** 
    * Handles the HTTP <code>POST</code> method.
    * @param request servlet request
    * @param response servlet response
    */
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
        processRequest(request, response);
    }

    /** 
    * Returns a short description of the servlet.
    */
    public String getServletInfo() {
        return "Nible Metadata Stream servlet that provides for downloading the content from server.";
    }
    // </editor-fold>
}