編輯:關於Android編程
本地:
先看下項目結構
MainActivity.java<喎?/kf/ware/vc/" target="_blank" class="keylink">vcD4KPHA+PC9wPgo8cHJlIGNsYXNzPQ=="brush:java;">package com.huxq.uploadexample; import java.io.File; import android.annotation.SuppressLint; import android.app.Activity; import android.app.ProgressDialog; import android.os.Bundle; import android.os.Environment; import android.os.Handler; import android.os.Message; import android.util.Log; import android.view.View; import android.widget.Toast; public class MainActivity extends Activity implements OnUploadListener { // 服務器路徑,換成自己的 private String urlString = "http://192.168.1.2:8080/UploadTest/Upload"; /** * 上傳文件的路徑 */ String filePath; /** * 上傳的文件名 */ String fileName; ProgressDialog dialog; /** * 在讀取文件流的時候,同一進度會多次回調,通過這個標記,只有在進度更新的情況下才會更新ui 節省資源 */ int oldProcess; @SuppressLint("HandlerLeak") private Handler handler = new Handler() { public void handleMessage(android.os.Message msg) { Log.i("process", "process" + msg.arg1); dialog.setProgress(msg.arg1); // 第一次沒有顯示dialog的時候顯示dialog if (!dialog.isShowing()) { Log.i("process", "show"); dialog.show(); } else { if (msg.arg1 == 100) {// 提示用戶上傳完成 dialog.dismiss(); toast("上傳完成!"); } } }; }; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); initProgressDialog(); } public void upLoad(View v) { if (Environment.getExternalStorageState().equals( Environment.MEDIA_MOUNTED)) { // toast("上傳"); String sdcardPath = Environment.getExternalStorageDirectory() .getAbsolutePath(); filePath = sdcardPath + "/Abook/"; File file = new File(filePath); // 這裡我選的是Abook文件夾下第五個文件上傳,得根據自己的實際情況來,否則肯定出錯。 fileName = file.list()[4]; filePath += fileName; Log.i("file.size", "size=" + file.list().length + "filePath" + filePath); } else { toast("沒有內存卡"); return; } new Thread() { public void run() { try { String response = HttpUtil.sendFile(urlString, filePath, fileName, MainActivity.this); Log.i("response", "response" + response); } catch (Exception e) { e.printStackTrace(); } }; }.start(); } @Override public void onUpload(double process) { process = process * 100; int currentProcess = (int) process; dialog.setProgress(currentProcess); // 避免重復發消息,可以把if給去掉看看會發生什麼 if (currentProcess > oldProcess) { Message msg = handler.obtainMessage(); msg.arg1 = (int) process; handler.sendMessage(msg); } oldProcess = currentProcess; } public void initProgressDialog() { dialog = new ProgressDialog(this); dialog.setMax(100); dialog.setProgress(0); dialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL); dialog.setCancelable(false); dialog.setCanceledOnTouchOutside(false); dialog.setTitle("正在努力上傳..."); } public void toast(String text) { Toast.makeText(getApplicationContext(), text, Toast.LENGTH_SHORT) .show(); } } HttpUtil.java
public static String sendFile(String urlPath, String filePath, String newName,OnUploadListener listener) throws Exception { String end = "\r\n"; String twoHyphens = "--"; String boundary = "******"; URL url = new URL(urlPath); HttpURLConnection con = (HttpURLConnection) url.openConnection(); //下載需要將setDoInput方法的參數值設為true con.setDoInput(true); //上傳需要將setDoOutput方法的參數值設為true con.setDoOutput(true); //禁止HttpURLConnection使用緩存 con.setUseCaches(false); //使用POST請求,必須大寫 con.setRequestMethod("POST"); //以下三行設置http請求頭信息 con.setRequestProperty("Connection", "Keep-Alive"); con.setRequestProperty("Charset", "UTF-8"); //在模擬web頁面向服務器端上傳文件時,每個文件的開頭需要有一個分界符, //分界符需要在http請求頭中指定。boundary是任意一個字符串,一般為****** con.setRequestProperty("Content-Type", "multipart/form-data;boundary=" + boundary); DataOutputStream ds = new DataOutputStream(con.getOutputStream()); ds.writeBytes(twoHyphens + boundary + end); //上傳文件相關信息,這些信息包括請求參數名,上傳文件名,文件類型,但並不限於此 ds.writeBytes("Content-Disposition: form-data; " + "name=\"file1\";filename=\"" + newName + "\"" + end); ds.writeBytes(end); //獲得文件的輸入流,通過流傳輸文件。在這裡我重寫了FileInputStream,為了監聽上傳進度 CustomFileInputStream fStream = new CustomFileInputStream(filePath); fStream.setOnUploadListener(listener); /* 設置每次寫入1024bytes */ int bufferSize = 1024; byte[] buffer = new byte[bufferSize]; int length = -1; // 從文件讀取數據至緩沖區 while ((length = fStream.read(buffer)) != -1) { //將資料寫入DataOutputStream中 ds.write(buffer, 0, length); } ds.writeBytes(end); ds.writeBytes(twoHyphens + boundary + twoHyphens + end); fStream.close(); ds.flush(); //上傳完成以後獲取服務器的反饋 InputStream is = con.getInputStream(); int ch; StringBuffer b = new StringBuffer(); while ((ch = is.read()) != -1) { b.append((char) ch); } ds.close(); return b.toString(); }CustomFileInputStream.java
package com.huxq.uploadexample; import java.io.File; import java.io.FileDescriptor; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.IOException; public class CustomFileInputStream extends FileInputStream { private OnUploadListener listener; private int total, done; private double process; public CustomFileInputStream(File file) throws FileNotFoundException { super(file); available(); } public CustomFileInputStream(FileDescriptor fd) { super(fd); available(); } public CustomFileInputStream(String path) throws FileNotFoundException { super(path); available(); } @Override public int read(byte[] buffer, int byteOffset, int byteCount) throws IOException { done += byteCount; process = 1.0 * done / total; if (listener != null) { listener.onUpload(process); } return super.read(buffer, byteOffset, byteCount); } public void setOnUploadListener(OnUploadListener listener) { this.listener = listener; } @Override public int available() { try { // 獲取文件的總大小 total = super.available(); } catch (IOException e) { e.printStackTrace(); } return total; } }OnUploadListener.java
package com.huxq.uploadexample; public interface OnUploadListener { void onUpload(double process); }
服務器端通過一個servlet來接收文件流,然後寫入磁盤就行了。
Upload.java
package com.huxq.test; import java.io.File; import java.io.FileOutputStream; import java.io.IOException; import java.util.Iterator; import java.util.List; 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 org.apache.commons.fileupload.FileItem; import org.apache.commons.fileupload.FileItemFactory; import org.apache.commons.fileupload.FileUploadException; import org.apache.commons.fileupload.disk.DiskFileItemFactory; import org.apache.commons.fileupload.servlet.ServletFileUpload; /** * Servlet implementation class Upload */ @WebServlet("/Upload") public class Upload extends HttpServlet { private static final long serialVersionUID = 1L; /** * 文件保存路徑 */ private final String savaPath="E:\\uploads/"; /** * Default constructor. */ public Upload() { } /** * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse * response) */ protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { boolean isMultipart = ServletFileUpload.isMultipartContent(request); if (isMultipart) { FileItemFactory factory = new DiskFileItemFactory(); ServletFileUpload upload = new ServletFileUpload(factory); List items; try { items = upload.parseRequest(request); Iterator iter = items.iterator(); // 可以接收多個文件 while (iter.hasNext()) { FileItem item = (FileItem) iter.next(); if (item.isFormField()) { // 普通文本信息處理 String paramName = item.getFieldName(); String paramValue = item.getString(); System.out.println(paramName + ":" + paramValue); } else { // 上傳文件信息處理 String fileName = item.getName(); byte[] data = item.get(); String filePath = savaPath + fileName; File file = new File(savaPath); if (!file.exists()) { file.mkdirs(); } System.out.println("filePath:" + filePath); File file2 = new File(filePath); if (file2.exists()) file2.delete(); FileOutputStream fos = new FileOutputStream(file2); fos.write(data); fos.close(); } } response.getWriter().write("UPLOAD_SUCCESS"); } catch (FileUploadException e) { e.printStackTrace(); response.getWriter().write("UPLOAD_FAILED"); } } } /** * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse * response) */ protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doGet(request, response); } }
這裡需要兩個jar包,分別是commons-fileupload-1.3.1.jar和commons-io-2.4.jar
所有想說的都在代碼裡了,如果有不清楚的可以下載下載Demo或者留言一起探討。
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