MyServlet.java
 package com.synnex.servlet;
 
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.io.PrintWriter;
 import java.util.List;
 
 import javax.servlet.ServletConfig;
 import javax.servlet.ServletException;
 import javax.servlet.ServletOutputStream;
 import javax.servlet.http.HttpServlet;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 
 import android.content.Context;
 import android.content.Intent;
 import android.content.pm.ApplicationInfo;
 import android.content.pm.PackageInfo;
 import android.content.pm.PackageManager;
 import android.content.pm.PackageManager.NameNotFoundException;
 import android.content.pm.ResolveInfo;
 import android.graphics.Bitmap;
 import android.graphics.Canvas;
 import android.graphics.PixelFormat;
 import android.graphics.drawable.Drawable;
 import android.util.Log;
 
 public class MyServlet extends HttpServlet
 {
 private static final long serialVersionUID = -4258280559794945071L;
 private final String TAG = "MyServlet";
 private final String METHOD = "method";
 
 private Context context;
 
 public void init(ServletConfig config) throws ServletException
 {
 super.init(config);
 context = (Context)config.getServletContext().getAttribute("org.mortbay.ijetty.context");
 Log.v(TAG, "## init android context success ##");
 }
 
 protected void service(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException
 {
 String method = request.getParameter(METHOD);
 if("listApp".equals(method))
 {
 response.setContentType("text/html; charset=UTF-8");
 listApp(request, response);
 }
 else if("appIcon".equals(method))
 {
 appIcon(request, response);
 }
 else
 {
 response.setContentType("text/html; charset=UTF-8");
 sayHello(request, response);
 }
 }
 
 private void appIcon(HttpServletRequest request, HttpServletResponse response) throws IOException
 {
 response.setContentType("image/JPEG");
 ServletOutputStream out = response.getOutputStream();
 PackageManager pm = context.getPackageManager();
 try
 {
 Drawable icon = pm.getApplicationIcon(request.getParameter("id"));
 ByteArrayOutputStream baos = new ByteArrayOutputStream();
 drawableToBitmap(icon).compress(Bitmap.CompressFormat.PNG, 100, baos);
 byte[] b = baos.toByteArray();
 out.write(b);
 out.flush();
 }
 catch (NameNotFoundException e)
 {
 Log.e(TAG, "get app icon error : ", e);
 out.write("error".getBytes("UTF-8"));
 }
 response.flushBuffer();
 }
 
 private void sayHello(HttpServletRequest request, HttpServletResponse response) throws IOException
 {
 PrintWriter writer = response.getWriter();
 writer.write("Hello World!!!");
 writer.flush();
 response.flushBuffer();
 }
 
 private void listApp(HttpServletRequest request, HttpServletResponse response) throws IOException
 {
 Intent mainIntent = new Intent(Intent.ACTION_MAIN, null);
 mainIntent.addCategory(Intent.CATEGORY_LAUNCHER);
 List<ResolveInfo> apps = context.getPackageManager().queryIntentActivities(mainIntent, 0);
 PackageManager pm = context.getPackageManager();
 
 StringBuilder buf = new StringBuilder(500);
 buf.append("<table>")
 .append("<tr>")
 .append("<th>App Name</th>")
 .append("<th>App Version</th>")
 .append("<th>Package Name</th>")
 .append("<th>App Icon</th>")
 .append("</tr>");
 String imgBaseUrl = request.getContextPath() + request.getServletPath() + "?" + METHOD + "=appIcon";
 Log.v(TAG, imgBaseUrl);
 for(ResolveInfo info : apps)
 {
 try
 {
 PackageInfo appInfo = pm.getPackageInfo(info.activityInfo.packageName, 0);
 if((appInfo.applicationInfo.flags & ApplicationInfo.FLAG_SYSTEM) <= 0)
 {
 buf.append("<tr>")
 .append("<td>").append(appInfo.applicationInfo.loadLabel(pm)).append("</td>")
 .append("<td>").append(appInfo.versionName).append("</td>")
 .append("<td>").append(appInfo.packageName).append("</td>")
 .append("<td><img width='50px' height='50px' src='http://cancait.blog.163.com/blog/").append(imgBaseUrl).append("&id=").append(appInfo.packageName).append("'/></td>")
 .append("<td></td>")
 .append("</tr>");
 }
 }
 catch (NameNotFoundException e)
 {
 Log.e(TAG, "get app info error: ", e);
 continue;
 }
 }
 
 buf.append("</table>");
 
 PrintWriter writer = response.getWriter();
 writer.write(buf.toString());
 writer.flush();
 response.flushBuffer();
 }
 
 private static Bitmap drawableToBitmap(Drawable drawable)
 {
 int w = drawable.getIntrinsicWidth();
 int h = drawable.getIntrinsicHeight();
 
 Bitmap.Config config = drawable.getOpacity() != PixelFormat.OPAQUE ? Bitmap.Config.ARGB_8888 : Bitmap.Config.RGB_565;
 Bitmap bitmap = Bitmap.createBitmap(w, h, config);
 Canvas canvas = new Canvas(bitmap);
 drawable.setBounds(0, 0, w, h);
 drawable.draw(canvas);
 return bitmap;
 }
 }

在浏览器中输入：http://{android_ip}:8080/MyServlet?method=listApp

显示结果：