Question

我需要从光盘中读取一张图片，但我有FileNotFoundException！

try {

    fileInputStream = new FileInputStream(new File("C:/wakaicon.png"));

} catch(FileNotFoundException e) {

    Log.e("DEBUG", "[Picture Not Found]");
}

Answer 1

在android中，我们无法从光盘的任何部分获取文件。您必须在模拟器或设备中创建外部存储，并且必须提供类似“mnt / sdcard / yourfolder / yourfile。”的路径。

希望这会对你有所帮助。

你也可以这样试试。

File dir = Environment.getExternalStorageDirectory();
File yourFile = new File(dir, "path/to/the/file/inside/the/sdcard.ext");

Answer 2

模拟器是PC上的一个独立虚拟机 - adb是将文件推送到外部SD卡或其他目录的解决方案（这里是指南：http://developer.android.com/tools/help/adb.html）。您无法在应用中访问您的硬盘。要访问外部目录中的文件，请尝试以下代码：

getExternalStorageDirectory ()

它返回一个文件。以下是有关它的文档：http://developer.android.com/reference/android/os/Environment.html#getExternalStorageDirectory()

编辑：您可以将带有adb的文件推送到外部SD卡，然后您可以尝试类似

的内容

File env = Enviroment.getExternalStorageDirectory()
File folder = new File(env,"Pictures/yourNewPic")
if(!folder.exists()){folder.mkdirs()}

需要<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"></uses-permission> in your manifest.

Answer 3

我找到了解决问题的方法...... 1.创建SD卡（通过编辑AVD） 2.打开文件资源管理器（IDE - ＆gt;窗口 - ＆gt;显示视图 - ＆gt;文件浏览） 3.将图片添加到SD CARD目录

package com.example.wakauploadpicture;

import java.io.BufferedReader;
import java.io.ByteArrayOutputStream;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URI;
import java.net.URISyntaxException;
import java.net.URL;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Bitmap.CompressFormat;
import android.os.Environment;
import android.util.Log;
import android.widget.Toast;


public class handlePicture {
    handlePicture(){}
    //
    @SuppressWarnings("deprecation")
    public boolean handlePicture(String filePath, String mimeType) {       
        HttpURLConnection connection = null;
        DataOutputStream outStream = null;
        DataInputStream inStream = null;

        String lineEnd = "-----------------------------16572156320853";
        String twoHyphens = "--";
        String boundary = "---------------------------29463111463415";

        int bytesRead, bytesAvailable, bufferSize;

        byte[] buffer;

        int maxBufferSize = 1*1024*1024;

        String urlString = "http://192.168.224.37:8081/waUpload/upload/uploadHandlers.js";
        Log.v("State : ",Environment.getExternalStorageState());
        Log.v("",Environment.getExternalStorageDirectory().getAbsolutePath());
        final File file = new File(Environment.getExternalStorageDirectory()
                .getAbsolutePath(), "wakaicon.png");
        try {
            FileInputStream fileInputStream = null;
            try {               
                fileInputStream = new FileInputStream(file);
            } catch(FileNotFoundException e) {              
                Log.e("DEBUG", "[Picture Not Found]");
            }
            URL url = new URL(urlString);
            connection = (HttpURLConnection) url.openConnection();
            //indicates that the application intends to read data from the URL connection. 
            connection.setDoInput(true);
            //indicates that the application intends to write data to the URL connection. 
            connection.setDoOutput(true);           
            connection.setUseCaches(true);

            //Set the method for the URL request, one of: POST
            connection.setRequestMethod("POST");
            connection.setRequestProperty("Accept", "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8");
            connection.setRequestProperty("Accept-Encoding", "gzip, deflate");
            connection.setRequestProperty("Connection", "Keep-Alive");
            connection.setRequestProperty("Content-Type", "multipart/form-data");
            connection.setRequestProperty("Referer", "http://127.0.0.1:8081/index.waPage/index.html");

            //connection.setRequestProperty("Content-Length", ""+file.length());
            Log.v("Content-Length", ""+file.length());
            outStream = new DataOutputStream(connection.getOutputStream());

            outStream.writeBytes(boundary);
            outStream.writeBytes("Content-Disposition: form-data; name=\"filesToUpload\"; filename=\"" + "wakaicon.png");
            outStream.writeBytes("Content-Type: "+ mimeType);
//        
//          bytesAvailable = fileInputStream.available();
//          bufferSize = Math.min(bytesAvailable, maxBufferSize);
//          buffer = new byte[bufferSize];
//
//          bytesRead = fileInputStream.read(buffer, 0, bufferSize);
//
//            while (bytesRead > 0) {
//                outStream.write(buffer, 0, bufferSize);
//                Log.v("Buffer : ",buffer.toString());
//              bytesAvailable = fileInputStream.available();
//              bufferSize = Math.min(bytesAvailable, maxBufferSize);
//              bytesRead = fileInputStream.read(buffer, 0, bufferSize);
//              outStream.write(bytesRead);
//          }

            FileInputStream fis = null;
            try {
                fis = new FileInputStream(file);
            } catch (FileNotFoundException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            Bitmap bm = BitmapFactory.decodeStream(fis);
            ByteArrayOutputStream baos = new ByteArrayOutputStream();  
            bm.compress(Bitmap.CompressFormat.PNG, 100 , baos);    
            byte[] b = baos.toByteArray();
            for(int i=0;i<b.length;i++){
            Log.v("byte : ",""+b[i]);
            outStream.write(b[i]);
            }


            outStream.write(getBytesFromBitmap(bm));                
              outStream.writeBytes(twoHyphens+boundary);
              outStream.writeBytes("Content-Disposition: form-data; name=\"config\"");
              outStream.writeBytes("{\"folder\":\"tmp\",\"replace\":false,\"datasource\":{\"dsname\":\"Emloyee\",\"id\":\"5\",\"field\":\"photo\",\"saveOnDS\":true}}");
              outStream.writeBytes(boundary+twoHyphens);
            fileInputStream.close();
            outStream.flush();
            outStream.close();  
            connection.disconnect();
        } catch (MalformedURLException e) {
            Log.e("DEBUG", "[MalformedURLException while sending a picture]");
        } catch (IOException e) {
            Log.e("DEBUG", "[IOException while sending a picture]"); 
        }

        try {
               String sHeaderValue = connection.getResponseMessage();
               Log.v("Response : ",sHeaderValue);
               inStream = new DataInputStream( connection.getInputStream() );
               String str;

               while (( str = inStream.readLine()) != null) {
                   Log.v("str pic :",str);
                   if(str=="1") {
                       return true;
                   } else {
                       return false;
                   }
               }
               inStream.close();        
          } catch (IOException e){
              Log.e(e.toString(), "[IOException while sending a picture and receiving the response]");
          }
        return false;

    }


    public byte[] getBytesFromBitmap(Bitmap bitmap) {
        ByteArrayOutputStream stream = new ByteArrayOutputStream();
        bitmap.compress(CompressFormat.PNG, 70, stream);
        return stream.toByteArray();
    }
}

Android中的FileNotFoundException - 来自光盘

3 个答案: