Android开发之SDCardUtils工具类。java工具详细代码，附源代码。判断SD卡是否挂载等功能

package com.xiaobing.zhbj.utils;

import java.io.BufferedInputStream;

import java.io.BufferedOutputStream;

import java.io.ByteArrayOutputStream;

import java.io.File;

import java.io.FileInputStream;

import java.io.FileOutputStream;

import java.io.IOException;

import android.os.Environment;

/**

 *

 *

 * @author ：QQ:986945193

 *

 * @新浪微博 ：http://weibo.com/mcxiaobing

 *

 * @version V1.0正式版

 *

 * SDCard工具类

 *

 */

public class SDCardUtils {

	/**

	 * 判断SD卡是否挂载

	 *

	 * @return

	 */

	public static boolean isMounted() {

		return Environment.getExternalStorageState().equals(

				Environment.MEDIA_MOUNTED);

	} 

	// 得到SD卡的根路径

	public static String getSDPath() {

		if (isMounted()) {

			return Environment.getExternalStorageDirectory().getAbsolutePath();

		}

		return null;

	}

	// 将文件保存到SD卡中

	public static boolean saveFileIntoSDCard(byte[] data, String path,

			String fileName) {

		if (isMounted()) {

			BufferedOutputStream bos = null;

			try {

				String filePath = getSDPath() + File.separator + path;

				File file = new File(filePath);

				if (!file.exists()) {

					file.mkdirs();

				}

				bos = new BufferedOutputStream(new FileOutputStream(new File(

						file, fileName)));

				bos.write(data, 0, data.length);

				bos.flush();

				return true;

			} catch (Exception e) {

				e.printStackTrace();

			} finally {

				if (bos != null) {

					try {

						bos.close();

					} catch (IOException e1) {

						e1.printStackTrace();

					}

				}

			}

		}

		return false;

	}

	// 从SD卡中取出存储的文件

	public static byte[] getFileFromSDCard(String filePath) {

		if (isMounted()) {

			File file = new File(filePath);

			BufferedInputStream bis = null;

			ByteArrayOutputStream baos = null;

			if (file.exists()) {

				try {

					baos = new ByteArrayOutputStream();

					bis = new BufferedInputStream(new FileInputStream(file));

					int len = 0;

					byte[] buffer = new byte[1024 * 8];

					while ((len = bis.read(buffer)) != -1) {

						baos.write(buffer, 0, len);

						baos.flush();

					}

					return baos.toByteArray();

				} catch (Exception e) {

					e.printStackTrace();

				} finally {

					if (bis != null) {

						try {

							bis.close();

							baos.close();

						} catch (IOException e) {

							e.printStackTrace();

						}

					}

				}

			}

		}

		return null;

	}

}