由Kevin Weiner所撰寫，
下面以一個簡單的例子來演示如何使用。
需求如下：
- 寫一個servlet，其接到request後可輸出一個GIF動畫。
- 在一個htm內用<img>的src接接看測試
實作的檔案結構如下：
各檔內容如下(AnimatedGifEncoder.java就不介紹了)：
- index.html
<!DOCTYPE html> <html> <head> <title>Animated Gif Test</title> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <style> /* 為img加上背景色，測試透明GIF動畫 */ img { background-color: black; } </style> </head> <body> <div>Animated Gif Test</div> <!-- 測試GIF動畫 --> <img src="AnimatedGif.do" /> </body> </html> - AnimatedGif.java
/* * To change this license header, choose License Headers in Project Properties. * To change this template file, choose Tools | Templates * and open the template in the editor. */ package servlet; import java.awt.Color; import java.awt.Graphics2D; import java.awt.image.BufferedImage; import java.io.IOException; import java.io.OutputStream; import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import tools.AnimatedGifEncoder; @WebServlet(name = "AnimatedGif", urlPatterns = {"/AnimatedGif.do"}) public class AnimatedGif extends HttpServlet { /** * Processes requests for both HTTP <code>GET</code> and <code>POST</code> * methods. * * @param request servlet request * @param response servlet response * @throws ServletException if a servlet-specific error occurs * @throws IOException if an I/O error occurs */ protected void processRequest(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { OutputStream o = response.getOutputStream(); response.setContentType("image/gif"); //設定-- header -- ContentType Color transparentColor = Color.WHITE; AnimatedGifEncoder encoder = new AnimatedGifEncoder(); encoder.setTransparent(transparentColor); //設定透明色 encoder.setDelay(100); //設定frame之間的間隔 (毫秒) encoder.setRepeat(0); //設定重覆迴圈次數(不設就是不重覆)， 0:無限, 1:重覆一次... encoder.start(o); //綁定OutputStream //產生畫布 BufferedImage generatedImage = new BufferedImage(100, 100, BufferedImage.TYPE_INT_ARGB); //產生繪圖工具 Graphics2D graphics2D = generatedImage.createGraphics(); for (int i = 0; i < 10 ; i++){ //畫底色 graphics2D.setColor(transparentColor); graphics2D.fillRect(0, 0, generatedImage.getWidth(), generatedImage.getHeight()); //畫圓圈 graphics2D.setColor(Color.RED); graphics2D.drawOval(i*3, 25, 50, 50); //加到GIF動畫frame中 encoder.addFrame(generatedImage); } graphics2D.dispose(); //釋放資源 encoder.finish(); //GIF動畫結束 //串流輸出 o.flush(); o.close(); } // <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 * @throws ServletException if a servlet-specific error occurs * @throws IOException if an I/O error occurs */ @Override 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 * @throws ServletException if a servlet-specific error occurs * @throws IOException if an I/O error occurs */ @Override protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { processRequest(request, response); } /** * Returns a short description of the servlet. * * @return a String containing servlet description */ @Override public String getServletInfo() { return "Short description"; }// </editor-fold> }
原始碼下載：
AnimatedGifEncoderTest.7z
參考資料：
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