您可以从文件中加载内容。考虑文件在资产文件夹中。

public static InputStream loadInputStreamFromAssetFile(Context context, String fileName){
    AssetManager am = context.getAssets();
    try {
        InputStream is = am.open(fileName);
        return is;
    } catch (IOException e) {
        e.printStackTrace();
    }
    return null;
}

public static String loadContentFromFile(Context context, String path){
    String content = null;
    try {
        InputStream is = loadInputStreamFromAssetFile(context, path);
        int size = is.available();
        byte[] buffer = new byte[size];
        is.read(buffer);
        is.close();
        content = new String(buffer, "UTF-8");
    } catch (IOException ex) {
        ex.printStackTrace();
        return null;
    }
    return content;
}

现在可以通过调用函数来获取内容，如下所示

String json= FileUtil.loadContentFromFile(context, "data.json");

考虑到数据。json存储在Application\app\src\main\assets\data.json中

迟到总比不到好。

在某些情况下，我很难逐行阅读文件。 下面的方法是到目前为止我发现的最好的方法，我推荐它。

使用:字符串yourData = LoadData(“YourDataFile.txt”);

YourDataFile.txt假定驻留在资产/

 public String LoadData(String inFile) {
        String tContents = "";

    try {
        InputStream stream = getAssets().open(inFile);

        int size = stream.available();
        byte[] buffer = new byte[size];
        stream.read(buffer);
        stream.close();
        tContents = new String(buffer);
    } catch (IOException e) {
        // Handle exceptions here
    }

    return tContents;

 }

读取和写入文件总是冗长且容易出错。避免这些答案，使用Okio即可:

public void readLines(File file) throws IOException {
  try (BufferedSource source = Okio.buffer(Okio.source(file))) {
    for (String line; (line = source.readUtf8Line()) != null; ) {
      if (line.contains("square")) {
        System.out.println(line);
      }
    }
  }
}

您可以从文件中加载内容。考虑文件在资产文件夹中。

public static InputStream loadInputStreamFromAssetFile(Context context, String fileName){
    AssetManager am = context.getAssets();
    try {
        InputStream is = am.open(fileName);
        return is;
    } catch (IOException e) {
        e.printStackTrace();
    }
    return null;
}

public static String loadContentFromFile(Context context, String path){
    String content = null;
    try {
        InputStream is = loadInputStreamFromAssetFile(context, path);
        int size = is.available();
        byte[] buffer = new byte[size];
        is.read(buffer);
        is.close();
        content = new String(buffer, "UTF-8");
    } catch (IOException ex) {
        ex.printStackTrace();
        return null;
    }
    return content;
}

现在可以通过调用函数来获取内容，如下所示

String json= FileUtil.loadContentFromFile(context, "data.json");

考虑到数据。json存储在Application\app\src\main\assets\data.json中

在MainActivity.java

@Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        TextView tvView = (TextView) findViewById(R.id.tvView);

        AssetsReader assetsReader = new AssetsReader(this);
        if(assetsReader.getTxtFile(your_file_title)) != null)
        {
            tvView.setText(assetsReader.getTxtFile(your_file_title)));
        }
    }

此外，您还可以创建单独的类来完成所有工作

public class AssetsReader implements Readable{

    private static final String TAG = "AssetsReader";


    private AssetManager mAssetManager;
    private Activity mActivity;

    public AssetsReader(Activity activity) {
        this.mActivity = activity;
        mAssetManager = mActivity.getAssets();
    }

    @Override
    public String getTxtFile(String fileName)
    {
        BufferedReader reader = null;
        InputStream inputStream = null;
        StringBuilder builder = new StringBuilder();

        try{
            inputStream = mAssetManager.open(fileName);
            reader = new BufferedReader(new InputStreamReader(inputStream));

            String line;

            while((line = reader.readLine()) != null)
            {
                Log.i(TAG, line);
                builder.append(line);
                builder.append("\n");
            }
        } catch (IOException ioe){
            ioe.printStackTrace();
        } finally {

            if(inputStream != null)
            {
                try {
                    inputStream.close();
                } catch (IOException ioe){
                    ioe.printStackTrace();
                }
            }

            if(reader != null)
            {
                try {
                    reader.close();
                } catch (IOException ioe)
                {
                    ioe.printStackTrace();
                }
            }
        }
        Log.i(TAG, "builder.toString(): " + builder.toString());
        return builder.toString();
    }
}

在我看来，最好创建一个界面，但这不是必要的

public interface Readable {
    /**
     * Reads txt file from assets
     * @param fileName
     * @return string
     */
    String getTxtFile(String fileName);
}

Scanner类可以简化这一点。

        StringBuilder sb=new StringBuilder();
        Scanner scanner=null;
        try {
            scanner=new Scanner(getAssets().open("text.txt"));
            while(scanner.hasNextLine()){
                sb.append(scanner.nextLine());
                sb.append('\n');
            }
        } catch (IOException e) {
            e.printStackTrace();
        }finally {
            if(scanner!=null){try{scanner.close();}catch (Exception e){}}
        }
        mTextView.setText(sb.toString());