andriod学习——Content的openFileOutput 和 openFileInput操作文件

package demo.filerw.service;import java.io.ByteArrayOutputStream;import java.io.File;import java.io.FileInputStream;import java.io.FileOutputStream;import android.content.Context;import android.os.Environment;/** * 文件操作类 * @author janrone * @website http://hujl.sinaapp.com */public class FileService {private Context context;public FileService(Context context) {this.context = context;}//存储数据到文件public void saveName(String name) throws Exception{//context.getFilesDir();// 得到存放文件的系统目录 /data/data/<package name>/files//context.getCacheDir(); //缓存目录  /data/data/<package name>/cacheFileOutputStream outputStream=context.openFileOutput("deomfilerw.txt", Context.MODE_APPEND);outputStream.write(name.getBytes());outputStream.close();}//存储数据到sdcardpublic void saveNameToSDCard(String name) throws Exception{Environment.getExternalStorageDirectory(); //得到sdcard目录File file=new File("/sdcard","demosdcard.txt");FileOutputStream outputStream=new FileOutputStream(file);outputStream.write(name.getBytes());outputStream.close();}// 读取数据public String getName() throws Exception{FileInputStream inputStream=context.openFileInput("deomfilerw.txt");ByteArrayOutputStream outStream=new ByteArrayOutputStream();byte[] buffer=new byte[1024];int len=0;while ((len=inputStream.read(buffer))!=-1){outStream.write(buffer, 0, len);}outStream.close();byte[] data=outStream.toByteArray();String name=new String(data);return name;}}