Android文件读写

package com.xiva;import java.io.ByteArrayOutputStream;import java.io.File;import java.io.FileInputStream;import java.io.FileOutputStream;import java.io.IOException;import java.io.InputStream;import java.io.OutputStream;import android.test.AndroidTestCase;import android.util.Log;public class UnitTest extends AndroidTestCase{private static final String Tag = "UnitTest";public void testCall() throws Exception{int i = 1+1;i = this.compute(i);Log.i(Tag,"result="+i);}/** * @description 访问其他文件 * @throws Exception */public void testRead() throws Exception{File file = new File("/data/data/com.xiva.file/files/test.txt");InputStream iStream = new FileInputStream(file);String result = read(iStream);Log.i(Tag, result);}/** *  * @throws Exception */public void testWrite() throws Exception{File file = new File("/data/data/com.xiva.file/files/test.txt");FileOutputStream iStream = new FileOutputStream(file);save(iStream,"test");}public int compute(int FirNum){int secondNum = 10;int result = secondNum + FirNum;return result;}public static String read(InputStream iStream) throws IOException{ByteArrayOutputStream oStream = new ByteArrayOutputStream();byte[] buffer = new byte[1024];int len = -1;while((len = iStream.read(buffer)) != -1){oStream.write(buffer, 0, len);}byte[] data = oStream.toByteArray();iStream.close();oStream.close();return new String(data);}public static void save(OutputStream oStream,String content) throws IOException{oStream.write(content.getBytes());oStream.close();}}

贴出主要代码，其他代码见附件！

package com.xiva.file;import java.io.InputStream;import java.io.OutputStream;import android.app.Activity;import android.content.Context;import android.os.Bundle;import android.util.Log;import android.view.View;import android.widget.Button;import android.widget.EditText;import android.widget.TextView;import android.widget.Toast;public class FileActivity extends Activity {private EditText fileName;private EditText content;private TextView textContent;private static final String TAG = "FileActivity";    public void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.main);        fileName = (EditText) this.findViewById(R.id.fileName);        content  = (EditText) this.findViewById(R.id.content);        textContent = (TextView) this.findViewById(R.id.textContent);        Button saveBtn = (Button)this.findViewById(R.id.saveButton);        Button viewBtn = (Button)this.findViewById(R.id.viewButton);                saveBtn.setOnClickListener(listener);//保存按钮事件监听        viewBtn.setOnClickListener(listener);//查看按钮事件监听    }        private View.OnClickListener listener = new View.OnClickListener(){        public void onClick(View v) {// TODO Auto-generated method stubButton button     = (Button) v;String nameStr    = fileName.getText().toString().trim();        String contentStr = content.getText().toString();                switch(button.getId())        {        case R.id.saveButton :            int resId_s         = R.string.success;            OutputStream fileOS = null;    try {//    Context.MODE_APPEND----已append的模式保存文件内容,//    将现在的内容追加到原有文件内容之后//    Context.MODE_PRIVATE：为默认操作模式，代表该文件是私有数据，//    只能被应用本身访问，在该模式下，写入的内容会覆盖原文件的内容//    Context.MODE_WORLD_READABLE和Context.MODE_WORLD_WRITEABLE//    用来控制其他应用是否有权限读写该文件    fileOS  = FileActivity.this.openFileOutput(nameStr+".txt",    Context.MODE_WORLD_READABLE + Context.MODE_WORLD_WRITEABLE + Context.MODE_APPEND);    //下面写法即有读权限，也有写权限；如若又想用追加方式 ，加上"+Context.MODE_APPEND"即可.//    fileOS  = FileActivity.this.openFileOutput(nameStr+".txt",//    Context.MODE_WORLD_READABLE + Context.MODE_WORLD_WRITEABLE);    FileService.save(fileOS, contentStr);    } catch (Exception e) {    resId_s = R.string.failure;    e.printStackTrace();    }    //界面提示    Toast.makeText(FileActivity.this, resId_s, Toast.LENGTH_LONG).show();    Log.i(TAG, nameStr);    Log.i(TAG, contentStr);    break;        case R.id.viewButton :        int resId_v    = R.string.readSucc;        InputStream fileIS = null;        String contentSt   = null;try {fileIS    = FileActivity.this.openFileInput(nameStr+".txt");contentSt = FileService.read(fileIS);} catch (Exception e) {resId_v = R.string.readFail;e.printStackTrace();}textContent.setText(contentSt);Log.i(TAG, contentSt);Toast.makeText(FileActivity.this, resId_v, Toast.LENGTH_LONG).show();Log.i(TAG, nameStr);break;        }}           };    }