android文件读取

android文件读取

DataActivity.java

 1 package  com.pptv.file;
 2
 3 import  java.io.FileNotFoundException;
 4 import  java.io.InputStream;
 5 import  java.io.OutputStream;
 6
 7 import  android.app.Activity;
 8 import  android.content.Context;
 9 import  android.os.Bundle;
10 import  android.util.Log;
11 import  android.view.View;
12 import  android.widget.Button;
13 import  android.widget.EditText;
14 import  android.widget.TextView;
15 import  android.widget.Toast;
16
17 import  com.pptv.service.FileService;
18
19 public   class  DataActivity  extends  Activity  {
20    private EditText filenameText;
21    private EditText contentText;
22    private TextView resultView;
23    private static final String TAG = "DataActivity";
24
25    @Override
26    public void onCreate(Bundle savedInstanceState) {
27        super.onCreate(savedInstanceState);
28        setContentView(R.layout.main);
29        filenameText = (EditText) findViewById(R.id.edittext_filename);
30        contentText = (EditText) findViewById(R.id.textconetent);
31        resultView = (TextView) findViewById(R.id.textview_result);
32        Button button = (Button) findViewById(R.id.button_save);
33        Button buttonShow = (Button) findViewById(R.id.button_open);
34        button.setOnClickListener(listener);
35        buttonShow.setOnClickListener(listener);
36    }
37
38    private View.OnClickListener listener = new View.OnClickListener() {
39
40        @Override
41        public void onClick(View v) {
42            Button button = (Button) v;
43            String filename = filenameText.getText().toString();
44            switch (button.getId()) {
45            case R.id.button_save:
46                int resId = R.string.sucess;
47                String content = contentText.getText().toString();
48                OutputStream outStream;
49                try {
50                    outStream = DataActivity.this.openFileOutput(filename,
51                            Context.MODE_APPEND);
52                    FileService.save(outStream, content);
53                } catch (Exception e) {
54                    Log.e(TAG, e.toString());
55                    resId = R.string.error;
56                }
57                Toast.makeText(DataActivity.this, resId, Toast.LENGTH_LONG)
58                        .show();
59                break;
60
61            case R.id.button_open:
62                try {
63                    InputStream inStream = DataActivity.this
64                            .openFileInput(filename);
65                    String text = FileService.read(inStream, null);
66                    resultView.setText(text);
67                } catch (Exception e) {
68                    Log.e(TAG, e.toString());
69                    Toast.makeText(DataActivity.this, "读取失败", Toast.LENGTH_LONG).show();
70                }
71                break;
72
73            default:
74                break;
75            }
76
77        }
78    };
79
80}
81

FileServiceTest.java    ---单元测试模块

 1 package  com.pptv.file;
 2
 3 import  java.io.InputStream;
 4 import  java.io.OutputStream;
 5
 6 import  android.content.Context;
 7 import  android.test.AndroidTestCase;
 8 import  android.util.Log;
 9
10 import  com.pptv.service.FileService;
11
12 public   class  FileServiceTest  extends  AndroidTestCase  {
13    private static final String TAG = "FileServiceTest";
14
15    public void testSave() throws Exception {
16        OutputStream outStream = this.getContext().openFileOutput("songwei.txt", Context.MODE_PRIVATE);
17        FileService.save(outStream, "neironga!!!");
18    }
19
20    public void testRead() throws Exception {
21        InputStream inStream = this.getContext().openFileInput("songwei.txt");
22        String content = FileService.read(inStream, null);
23        Log.i(TAG, content);
24    }
25}
26

FileService.java  ----javabean模块

 1 package  com.pptv.service;
 2
 3 import  java.io.ByteArrayOutputStream;
 4 import  java.io.InputStream;
 5 import  java.io.OutputStream;
 6
 7 public   class  FileService  {
 8    /** *//**
 9     * 保存数据~~
10     * @param outStream
11     * @param content
12     * @throws Exception
13     */
14    public static void save(OutputStream outStream, String content) throws Exception {
15        outStream.write(content.getBytes());
16        outStream.close();
17    }
18    
19    /** *//**
20     * 读取数据~~
21     * @param inStream
22     * @param content
23     * @return
24     * @throws Exception
25     */
26    public static String read(InputStream inStream, String content) throws Exception {
27        ByteArrayOutputStream outStream = new ByteArrayOutputStream();
28        byte[] buffer = new byte[1024];
29        int len = -1;
30        while ((len = inStream.read(buffer)) != -1) {
31            outStream.write(buffer, 0, len);
32        }
33        byte[] data = outStream.toByteArray();
34        outStream.close();
35        inStream.close();
36        return new String(data);
37    }
38}
39

main.xml   ---布局文件

 1 <? xml version = " 1.0 "  encoding = " utf-8 " ?>
 2 < LinearLayout xmlns:android = " http://schemas.android.com/apk/res/android "
 3     android:orientation = " vertical "
 4     android:layout_width = " fill_parent "
 5     android:layout_height = " fill_parent "
 6      >
 7      < RelativeLayout xmlns:android = " http://schemas.android.com/apk/res/android "
 8     android:orientation = " vertical "
 9     android:layout_width = " fill_parent "
10     android:layout_height = " wrap_content "   >
11          < TextView
12             android:id = " @+id/filename "   
13             android:layout_width = " wrap_content "  
14             android:layout_height = " 10pt "
15              
16             android:text = " @string/file_name "
17              />
18             
19          < EditText
20             android:layout_width = " 100pt "  
21             android:layout_height = " wrap_content "
22             android:layout_toRightOf = " @id/filename "
23             android:layout_marginLeft = " 10pt "
24             android:id = " @+id/edittext_filename "
25              />
26      </ RelativeLayout >
27     
28      < TextView
29         android:layout_width = " wrap_content "
30         android:layout_height = " wrap_content "
31         android:text = " @string/txtcontent "
32      />
33      < EditText
34         android:id = " @+id/textconetent "
35         android:layout_width = " fill_parent "
36         android:layout_height = " wrap_content "
37         android:minLines = " 4 "
38      />
39     
40      < RelativeLayout xmlns:android = " http://schemas.android.com/apk/res/android "
41     android:orientation = " vertical "
42     android:layout_width = " fill_parent "
43     android:layout_height = " wrap_content "   >
44      < Button
45         android:id = " @+id/button_save "
46         android:layout_width = " wrap_content "
47         android:layout_height = " wrap_content "
48         android:text = " @string/button_save "
49          />
50      < Button
51         android:id = " @+id/button_open "
52         android:layout_width = " wrap_content "
53         android:layout_height = " wrap_content "
54         android:layout_toRightOf = " @id/button_save "
55         android:text = " @string/button_open "
56      />
57      </ RelativeLayout >
58     
59      < TextView
60         android:id = " @+id/textview_result "
61         android:layout_width = " fill_parent "
62         android:layout_height = " wrap_content "
63      />
64     
65 </ LinearLayout >

strings.xml

 1 <? xml version = " 1.0 "  encoding = " utf-8 " ?>
 2 < resources >
 3      < string name = " txtcontent " > 文本内容： </ string >
 4      < string name = " app_name " > 数据保存 </ string >
 5      < string name = " file_name " > 文件名称： </ string >
 6      < string name = " button_save " > 保  存 </ string >
 7      < string name = " error " > 保存失败 </ string >
 8      < string name = " sucess " > 保存成功 </ string >
 9      < string name = " button_open " > 打开文件 </ string >
10 </ resources >
11

AndroidManifest.xml

 1 <? xml version = " 1.0 "  encoding = " utf-8 " ?>
 2 < manifest xmlns:android = " http://schemas.android.com/apk/res/android "
 3        package = " com.pptv.file "
 4       android:versionCode = " 1 "
 5       android:versionName = " 1.0 " >
 6      < application android:icon = " @drawable/icon "  android:label = " @string/app_name " >
 7            // 测试权限
 8            < uses - library android:name = " android.test.runner "   />
 9           
10          < activity android:name = " .DataActivity "
11                   android:label = " @string/app_name " >
12              < intent - filter >
13                  < action android:name = " android.intent.action.MAIN "   />
14                  < category android:name = " android.intent.category.LAUNCHER "   />
15              </ intent - filter >
16          </ activity >
17
18      </ application >
19      < uses - sdk android:minSdkVersion = " 4 "   />
20      // 测试权限
21      < instrumentation android:name = " android.test.InstrumentationTestRunner "
22         android:targetPackage = " com.pptv.file "  android:label = " Tests for My App "   />
23 </ manifest >