Android文件存储详细完整示例

    package cc.cv;                import java.io.BufferedReader;        import java.io.BufferedWriter;        import java.io.FileInputStream;        import java.io.FileOutputStream;        import java.io.InputStreamReader;        import java.io.OutputStreamWriter;        import android.os.Bundle;        import android.app.Activity;        import android.content.Context;        import android.view.View;        import android.view.View.OnClickListener;        import android.widget.Button;        /**        * Demo描述:        * 文件存储详细示例        *         * 可利用Context的openFileOutput()方法将数据存储到文件中.        * 默认的存储路径为/data/data/<packageName>/files/        * 可利用Context的openFileInput()方法将数据从文件中读出        *         * 在Android中常用的存储方式:        * SharedPreferences,数据库,SD卡,文件存储.        * 对于最后一种方式平时用的不多,现在此写个例子        * 整理和复习一下.        *         * 注意事项:        * 文件存储是不需要权限的与在SD卡上进行文件存储是不一样的        */        public class MainActivity extends Activity {            private Button mSaveButton;            private Button mGetButton;            private Context mContext;            private String mFileName;            @Override            protected void onCreate(Bundle savedInstanceState) {                super.onCreate(savedInstanceState);                setContentView(R.layout.main);                init();            }                        private void init(){                mContext=this;                mFileName="testData";                mSaveButton=(Button) findViewById(R.id.saveButton);                mSaveButton.setOnClickListener(new ClickListenerImpl());                mGetButton=(Button) findViewById(R.id.getButton);                mGetButton.setOnClickListener(new ClickListenerImpl());            }                    private class ClickListenerImpl implements OnClickListener{                @Override                public void onClick(View view) {                    switch (view.getId()) {                    case R.id.saveButton:                        saveDataToFile(mContext,mFileName);                        break;                    case R.id.getButton:                        getDataFromFile(mContext,mFileName);                        break;                    default:                        break;                    }                }                            }                        /**            * 向File中保存数据            */            private void saveDataToFile(Context context,String fileName){                String data="Hello,All";                FileOutputStream fileOutputStream=null;                OutputStreamWriter outputStreamWriter=null;                BufferedWriter bufferedWriter=null;                try {                    fileOutputStream=context.openFileOutput(fileName, Context.MODE_PRIVATE);                    outputStreamWriter=new OutputStreamWriter(fileOutputStream);                    bufferedWriter=new BufferedWriter(outputStreamWriter);                    bufferedWriter.write(data);                } catch (Exception e) {                    e.printStackTrace();                }finally{                    try {                        if (bufferedWriter!=null) {                            bufferedWriter.close();                        }                    } catch (Exception e) {                        e.printStackTrace();                    }                }                            }                        /**            * 从File中读取数据            */            private void getDataFromFile(Context context,String fileName){                FileInputStream fileInputStream=null;                InputStreamReader inputStreamReader=null;                BufferedReader bufferedReader=null;                StringBuilder stringBuilder=null;                String line=null;                try {                    stringBuilder=new StringBuilder();                    fileInputStream=context.openFileInput(fileName);                    inputStreamReader=new InputStreamReader(fileInputStream);                    bufferedReader=new BufferedReader(inputStreamReader);                    while((line=bufferedReader.readLine())!=null){                        stringBuilder.append(line);                    }                    System.out.println("--->"+stringBuilder.toString());                } catch (Exception e) {                    e.printStackTrace();                }finally{                    try {                        if (bufferedReader!=null) {                            bufferedReader.close();                        }                    } catch (Exception e) {                        e.printStackTrace();                    }                }            }                            }  

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"        xmlns:tools="http://schemas.android.com/tools"        android:layout_width="match_parent"        android:layout_height="match_parent"        >            <Button            android:id="@+id/saveButton"            android:layout_width="wrap_content"            android:layout_height="wrap_content"            android:text="向File中保存数据"            android:layout_centerHorizontal="true"            android:layout_marginTop="100dp" />                         <Button            android:id="@+id/getButton"            android:layout_width="wrap_content"            android:layout_height="wrap_content"            android:text="从File中获取数据"            android:layout_centerHorizontal="true"            android:layout_marginTop="260dp" />        </RelativeLayout>