android文件读写源码

package cn.itcast.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; public class FileService { private Context context; public FileService(Context context) { this.context = context; } /** * 保存文件 * @param filename 文件名称 * @param content 文件内容 * @throws Exception */ public void save(String filename, String content) throws Exception{ FileOutputStream outStream = context.openFileOutput(filename, Context.MODE_PRIVATE); outStream.write(content.getBytes()); outStream.close(); } public void saveAppend(String filename, String content) throws Exception{// ctrl+shift+y/x FileOutputStream outStream = context.openFileOutput(filename, Context.MODE_APPEND); outStream.write(content.getBytes()); outStream.close(); } public void saveReadable(String filename, String content) throws Exception{ FileOutputStream outStream = context.openFileOutput(filename, Context.MODE_WORLD_READABLE); outStream.write(content.getBytes()); outStream.close(); } public void saveWriteable(String filename, String content) throws Exception{ FileOutputStream outStream = context.openFileOutput(filename, Context.MODE_WORLD_WRITEABLE); outStream.write(content.getBytes()); outStream.close(); } public void saveRW(String filename, String content) throws Exception{ FileOutputStream outStream = context.openFileOutput(filename, Context.MODE_WORLD_WRITEABLE+ Context.MODE_WORLD_READABLE); outStream.write(content.getBytes()); outStream.close(); } /** * 读取文件内容 * @param filename 文件名称 * @return 文件内容 * @throws Exception */ public String read(String filename) throws Exception{ ByteArrayOutputStream outStream = new ByteArrayOutputStream(); FileInputStream inStream = context.openFileInput(filename); byte[] buffer = new byte[1024]; int len = 0; while( (len = inStream.read(buffer)) != -1){ outStream.write(buffer, 0, len); } outStream.close(); inStream.close(); byte[] data = outStream.toByteArray(); return new String(data); } /** * 把文件保存到SDCard上 * @param filename 文件名称 * @param content 文件内容 * @throws Exception */ public void saveToSDCard(String filename, String content) throws Exception{ File file = new File(Environment.getExternalStorageDirectory(), filename); FileOutputStream outStream = new FileOutputStream(file); outStream.write(content.getBytes()); outStream.close(); } }