安卓开发，从相册或者相机中选择一张图片并裁剪，上传和下载。

一个图片上传下载的例子：

1：从相册或者相机选出或拍一张照片

2：裁剪

3：上传到服务器或者从服务器下载

本文最后附带源码

客户端代码：

打开系统自带的相册

Intent intent = new Intent(Intent.ACTION_PICK, null);
intent.setDataAndType(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, IMAGE_UNSPECIFIED);
startActivityForResult(intent, ALBUM_REQUEST_CODE);

其中 ALBUM_REQUEST_CODE为标识，int类型的变量，随你定

作为后面返回时判断的标识

打开系统自带的相机

intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
intent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(new File(Environment.
        getExternalStorageDirectory() + "/temp/", "temp.jpg")));
startActivityForResult(intent, CAMERA_REQUEST_CODE);

拍照或者相册选取完毕之后，开始裁剪

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {

    switch (requestCode) {
        case ALBUM_REQUEST_CODE:
            Log.i(TAG, "相册，开始裁剪");
            Log.i(TAG, "相册 [ " + data + " ]");
            if (data == null) {
                return;
            }
            startCrop(data.getData());
            break;
        case CAMERA_REQUEST_CODE:
            Log.i(TAG, "相机, 开始裁剪");
            File picture = new File(Environment.getExternalStorageDirectory()
                    + "/temp/temp.jpg");
            startCrop(Uri.fromFile(picture));
            break;
        case CROP_REQUEST_CODE:
            Log.i(TAG, "相册裁剪成功");
            Log.i(TAG, "裁剪以后 [ " + data + " ]");
            if (data == null) {
                // TODO 如果之前以后有设置过显示之前设置的图片 否则显示默认的图片
                return;
            }
            Bundle extras = data.getExtras();
            if (extras != null) {
                Bitmap photo = extras.getParcelable("data");
                ByteArrayOutputStream stream = new ByteArrayOutputStream();
                photo.compress(Bitmap.CompressFormat.JPEG, 75, stream);// (0-100)压缩文件
                File fImage = new File(Environment.getExternalStorageDirectory().getAbsolutePath() + "/temp/testImg.png");
                try {
                    fImage.createNewFile();
                    FileOutputStream iStream = new FileOutputStream(fImage);
                    photo.compress(Bitmap.CompressFormat.PNG, 100, iStream);
                } catch (Exception e) {
                    e.printStackTrace();
                }
                display.setImageBitmap(photo); //把图片显示在ImageView控件上

            }
            break;
        default:
            break;
    }

裁剪的方法为：

/**
 * 开始裁剪
 */
private void startCrop(Uri uri) {
    Intent intent = new Intent("com.android.camera.action.CROP");//调用Android系统自带的一个图片剪裁页面,
    intent.setDataAndType(uri, IMAGE_UNSPECIFIED);
    intent.putExtra("crop", "true");//进行修剪
    // aspectX aspectY 是宽高的比例
    intent.putExtra("aspectX", 1);
    intent.putExtra("aspectY", 1);
    // outputX outputY 是裁剪图片宽高
    intent.putExtra("outputX", 300);
    intent.putExtra("outputY", 500);
    intent.putExtra("return-data", true);
    startActivityForResult(intent, CROP_REQUEST_CODE);
}

上传到服务器：

/**
 * 上传到服务端
 */
private void upLoadToServlet(String temp_path) {
    HttpURLConnection conn = null;
    String BOUNDARY = "|"; // request头和上传文件内容分隔符
    try {
        URL url = new URL("http://169.254.186.44:8080/ImageDealWithProject/Test");
        conn = (HttpURLConnection) url.openConnection();
        conn.setConnectTimeout(5000);
        conn.setReadTimeout(30000);
        conn.setDoOutput(true);
        conn.setDoInput(true);
        conn.setUseCaches(false);
        conn.setRequestMethod("POST");
        conn.setRequestProperty("Connection", "Keep-Alive");
        conn.setRequestProperty("User-Agent",
                "Mozilla/5.0 (Windows; U; Windows NT 6.1; zh-CN; rv:1.9.2.6)");
        conn.setRequestProperty("Content-Type",
                "multipart/form-data; boundary=" + BOUNDARY);
        OutputStream out = new DataOutputStream(conn.getOutputStream());
        File file = new File(temp_path);
        String filename = file.getName();
        String contentType = "";
        if (filename.endsWith(".png")) {
            contentType = "image/png";
        }
        if (filename.endsWith(".jpg")) {
            contentType = "image/jpg";
        }
        if (filename.endsWith(".gif")) {
            contentType = "image/gif";
        }
        if (filename.endsWith(".bmp")) {
            contentType = "image/bmp";
        }
        if (contentType == null || contentType.equals("")) {
            contentType = "application/octet-stream";
        }
        StringBuffer strBuf = new StringBuffer();
        strBuf.append("\r\n").append("--").append(BOUNDARY).append("\r\n");
        strBuf.append("Content-Disposition: form-data; name=\"" + temp_path
                + "\"; filename=\"" + filename + "\"\r\n");
        strBuf.append("Content-Type:" + contentType + "\r\n\r\n");
        out.write(strBuf.toString().getBytes());
        DataInputStream in = new DataInputStream(new FileInputStream(file));
        int bytes = 0;
        byte[] bufferOut = new byte[1024];
        while ((bytes = in.read(bufferOut)) != -1) {
            out.write(bufferOut, 0, bytes);
        }
        in.close();
        byte[] endData = ("\r\n--" + BOUNDARY + "--\r\n").getBytes();
        out.write(endData);
        out.flush();
        out.close();

        // 读取返回数据
        StringBuffer buffer = new StringBuffer();
        BufferedReader reader = new BufferedReader(new InputStreamReader(conn.getInputStream(), "utf-8"));
        String line = null;
        while ((line = reader.readLine()) != null) {
            buffer.append(line).append("\n");
        }
        rsp = buffer.toString();
        reader.close();
        reader = null;
    } catch (Exception e) {
        e.printStackTrace();
    } finally {
        if (conn != null) {
            conn.disconnect();
            conn = null;
        }
    }

    System.out.println("文件url为：" + rsp);
}

从服务器下载：

/**
 * 保存和显示做完之后直接上传到服务端。
 * */
new Thread() {
    @Override
    public void run() {
        upLoadToServlet(Environment.getExternalStorageDirectory().getAbsolutePath() + "/temp/testImg.png");
    }
}.start();

这里基于方便，直接用了imageloader框架进行加载，

关于imageloader的jar包，本文最后的项目中有，关于具体用法请自行百度。

服务器代码：

服务器就一个servlet。

import java.io.BufferedInputStream;
import java.io.File;
import java.io.IOException;
import java.net.URL;
import java.util.Date;
import java.util.Iterator;
import java.util.List;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.commons.fileupload.DiskFileUpload;
import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;

public class Test extends HttpServlet {

	/**
	 * Constructor of the object.
	 */
	public Test() {
		super();
	}

	/**
	 * Destruction of the servlet. <br>
	 */
	public void destroy() {
		super.destroy(); // Just puts "destroy" string in log
		// Put your code here
	}

	/**
	 * The doGet method of the servlet. <br>
	 * 
	 * This method is called when a form has its tag value method equals to get.
	 * 
	 * @param request
	 *            the request send by the client to the server
	 * @param response
	 *            the response send by the server to the client
	 * @throws ServletException
	 *             if an error occurred
	 * @throws IOException
	 *             if an error occurred
	 */
	public void doGet(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {

		this.doPost(request, response);
	}

	/**
	 * The doPost method of the servlet. <br>
	 * 
	 * This method is called when a form has its tag value method equals to
	 * post.
	 * 
	 * @param request
	 *            the request send by the client to the server
	 * @param response
	 *            the response send by the server to the client
	 * @throws ServletException
	 *             if an error occurred
	 * @throws IOException
	 *             if an error occurred
	 */
	public void doPost(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		//将上传到servlet的缓存目录设置到文本下
		//之后从android端，就可以直接使用imageLoader来加载
		//具体的url地址为：http://ip:8080/ImageDealWithProject//images/filename
		String uploadDir = request.getSession().getServletContext().getRealPath("/")+ "\\images\\";
		System.out.println("有客户端访问");
		// 获得磁盘文件条目工厂
		DiskFileItemFactory factory = new DiskFileItemFactory();
		// 获取文件需要上传到的路径
		File file = new File(uploadDir);
		if (!file.exists()) {
			file.mkdirs();
		}
		factory.setRepository(file);
		// 设置 缓存的大小
		factory.setSizeThreshold(1024 * 1024);
		// 文件上传处理
		ServletFileUpload upload = new ServletFileUpload(factory);
		try {
			// 可以上传多个文件
			List<FileItem> list = (List<FileItem>) upload.parseRequest(request);
			for (FileItem item : list) {
				// 获取属性名字
				String name = item.getFieldName();
				// 如果获取的 表单信息是普通的 文本 信息
				if (item.isFormField()) {
					// 获取用户具体输入的字符串,因为表单提交过来的是 字符串类型的
					String value = item.getString();
					request.setAttribute(name, value);
				} else {
					// 获取路径名
					String value = item.getName();
					// 索引到最后一个反斜杠
					int start = value.lastIndexOf("\\");
					// 截取 上传文件的 字符串名字，加1是 去掉反斜杠，
					String filename = value.substring(start + 1);
					request.setAttribute(name, filename);
					// 写到磁盘上
					item.write(new File(uploadDir, filename));// 第三方提供的
					System.out.println("上传成功：" + filename);
					response.getWriter().print(filename);// 将路径返回给客户端
				}
			}

		} catch (Exception e) {
			System.out.println("上传失败");
			response.getWriter().print("上传失败：" + e.getMessage());
		}

	}

	/**
	 * Initialization of the servlet. <br>
	 * 
	 * @throws ServletException
	 *             if an error occurs
	 */
	public void init() throws ServletException {
		// Put your code here
	}

}

最后说明，代码部分引用多处其他来源，具体情况懒得找，，，

有任何问题可以留言或联系我

546288828

期待共同学习和进步

客户端代码：http://download.csdn.net/detail/qq_26559913/9541456

服务端代码：http://download.csdn.net/detail/qq_26559913/9541455