public class Utils {
public static List<Message> getMessages() {
//File file = new File("file:///android_asset/helloworld.txt");
AssetManager assetManager = getAssets();
InputStream ims = assetManager.open("helloworld.txt");
}
}
我正在使用这段代码试图从资产读取文件。我尝试了两种方法。首先，当使用文件时，我收到FileNotFoundException，当使用资产管理器getAssets()方法不被识别。 有什么解决办法吗?
当前回答
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;
}
其他回答
@HpTerm答案Kotlin版本:
private fun getDataFromAssets(activity: Activity): String {
var bufferedReader: BufferedReader? = null
var data = ""
try {
bufferedReader = BufferedReader(
InputStreamReader(
activity?.assets?.open("Your_FILE.html"),
"UTF-8"
)
) //use assets? directly if inside the activity
var mLine:String? = bufferedReader.readLine()
while (mLine != null) {
data+= mLine
mLine=bufferedReader.readLine()
}
} catch (e: Exception) {
e.printStackTrace()
} finally {
try {
bufferedReader?.close()
} catch (e: Exception) {
e.printStackTrace()
}
}
return data
}
AssetManager assetManager = getAssets();
InputStream inputStream = null;
try {
inputStream = assetManager.open("helloworld.txt");
}
catch (IOException e){
Log.e("message: ",e.getMessage());
}
ExceptionProof
It maybe too late but for the sake of others who look for the peachy answers.loadAssetFile()方法返回资产的纯文本，如果有任何错误，则返回defaultValue参数。
public static String loadAssetFile(Context context, String fileName, String defaultValue) {
String result=defaultValue;
InputStreamReader inputStream=null;
BufferedReader bufferedReader=null;
try {
inputStream = new InputStreamReader(context.getAssets().open(fileName));
bufferedReader = new BufferedReader(inputStream);
StringBuilder out= new StringBuilder();
String line = bufferedReader.readLine();
while (line != null) {
out.append(line);
line = bufferedReader.readLine();
}
result=out.toString();
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
Objects.requireNonNull(inputStream).close();
} catch (Exception e) {
e.printStackTrace();
}
try {
Objects.requireNonNull(bufferedReader).close();
} catch (Exception e) {
e.printStackTrace();
}
}
return result;
}
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());
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);
}
}
}
}
