在QuoteBank.java中设置一个私有变量：

private Context mContext;

设置构造函数：

public QuoteBank(Context context) {
   this.mContext = context;
}

然后在你的活动中实例化它,

QuoteBank quoteBank = new QuoteBank(context);

可以通过this命令或Activity.this在活动中调用上下文变量,其中将“Activity”替换为您的活动名称.或者,如果您在片段内,则可以从onCreateView(…)方法中的View对象获取上下文.通常通过调用view.getContext().

现在,在您抓取资产的方法中,您可以使用上下文：

InputStream is = mContext.getAssets().open("QuotesMonkeyBusiness.txt")

既然您正在使用android studio,您可以创建一个main(String [] args){…}方法并运行它或者只是启动模拟器并让它使用Log.d(…)来显示来自文件.

或者,您也可以使用以下方法：

AssetManager am = mContext.getAssets();
InputStream is = am.open("QuotesMonkeyBusiness.txt");

将QuoteBank作为单例实例也可能有意义,这可能会提高效率,尽管这完全取决于您的要求,可能是这样的：

List<String> allTextLines = QuoteBank.readFromFile(context,path_to_file);

然后在QuoteBank.java类中,您可以使用如下方法：

/**
* Created by AndyRoid on 5/23/15.
*/
public class QuoteBank {
 
private Context mContext;
 
public QuoteBank(Context context) {
    this.mContext = context;
}
 
public List<String> readLine(String path) {
    List<String> mLines = new ArrayList<>();
 
    AssetManager am = mContext.getAssets();
 
    try {
        InputStream is = am.open(path);
        BufferedReader reader = new BufferedReader(new InputStreamReader(is));
        String line;
 
        while ((line = reader.readLine()) != null)
            mLines.add(line);
    } catch (IOException e) {
        e.printStackTrace();
    }
 
    return mLines;
}

}

然后在我的MainActivity.java类中,我有以下内容：

/**
 * Created by AndyRoid on 5/23/15.
 */
public class MainActivity extends AppCompatActivity {
 
public static final String TAG = MainActivity.class.getSimpleName();
 
public static final String mPath = "adventur.txt";
private QuoteBank mQuoteBank;
private List<String> mLines;
 
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
 
    mQuoteBank = new QuoteBank(this);
    mLines = mQuoteBank.readLine(mPath);
    for (String string : mLines)
        Log.d(TAG,string);
}
 
@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.menu_main,menu);
    return true;
}
 
@Override
public boolean onOptionsItemSelected(MenuItem item) {
    // Handle action bar item clicks here. The action bar will
    // automatically handle clicks on the Home/Up button,so long
    // as you specify a parent activity in AndroidManifest.xml.
    int id = item.getItemId();
 
    //noinspection SimplifiableIfStatement
    if (id == R.id.action_settings) {
        return true;
    }
 
    return super.onOptionsItemSelected(item);
}
}

这是我的项目结构：

这是我从随机数据库下载的adventur.txt文件：

这是我的日志输出：

更新：为什么你不应该在Android中使用扫描仪

从官方文档：

http://developer.android.com/reference/java/util/Scanner.html

This class is not as useful as it might seem. It’s very inefficient for communicating between machines; you should use JSON,protobufs,or even XML for that. Very simple uses might get away with split(String). For input from humans,the use of locale-specific regular expressions make it not only expensive but also somewhat unpredictable.
The Scanner class is not thread-safe.

最后注意：

我强烈建议您阅读此处使用的所有对象的文档,以便您了解该过程.